FOUS30 KWBC 251559
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
1159 AM EDT Wed Jun 25 2025

Day 1
Valid 16Z Wed Jun 25 2025 - 12Z Thu Jun 26 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL OVER PORTIONS OF
NEW MEXICO, CENTRAL PLAINS AND MIDWEST...

...16Z Update...

Only minor areal modifications were made to better focus the=20
inherited Slight Risk areas based on the latest 12Z guidance, with=20
the prior forecast remaining ontrack overall. This included a=20
westward shift of the Slight Risk over the Upper Midwest where the=20
greater risk looks to be closer to the Upper Mississippi Valley=20
rather than eastward towards the Great Lakes. Still expect that the
higher-end threat within the Slight Risk exists in a corridor from
the central Missouri Valley northeastward towards the greater=20
Minneapolis area, where the greatest chance for rainfall totals of=20
3-4", locally 5-6", exists and may lead to more widespread=20
instances of flash flooding. For New Mexico/west Texas, the latest=20
guidance indicates that the more focused, higher-end threat within=20
the Slight Risk has concentrated southward over south-central New=20
Mexico (including the Sacramento Mountains and Ruidoso burn scar)=20
as well as western Texas from greater El Paso eastward through the=20
Guadalupe mountains. This covers the region with the greatest=20
potential for rainfall totals upwards of 2", locally 3".=20

Putnam

...Previous Discussion...

...New Mexico...

Despite a bit less areal coverage anticipated for convection
across New Mexico for Wednesday, scattered thunderstorms will still
cause problems after daytime initiation as ample heating during
the prime destabilization window (16-21z) will yield another threat
of heavy rainfall across the terrain and adjacent valleys across
NM. Main jet to the north will lift out of the area allowing for
less of a large scale ascent pattern that could maximize any
convective pattern over the region. Remnant elevated moisture
(PWATs) running between 1-2 standard deviations above normal on
the western flank of our ridge will still be located across the
state leaving an environment capable of heavy rainfall in any
convective cores that develop. Impacts the previous period were
felt over a large portion of the state leading to generally lower
FFG's bisecting much of the area expected to see a chance for
convection today. Latest HREF neighborhood probs for >3" are
running pretty high (50-70%) across places like El Paso and points
north within part of the Sacramento's, an area we have highlighted
the past several days. Modest probs (20-40%) for >3" extend all
the way up into the Sangre de Cristos with some smaller relative
mins mixed into the areal coverage. This is more a testament to the valley/terrain components littered over the state, so not all areas
will see impactful rainfall with this convective evolution.

The signal is sufficient enough to warrant a broad SLGT risk
within the state extending down through far West TX given the
current CAMs interpretation of scattered heavy convection likely to
impact portions of El Paso and Hudspeth counties through part of
the period. Some strong cells could even develop across the NM
Caprock as inferred by a few hi-res deterministic, likely due to
the favorable instability tongue positioned over the eastern side
of the state behind a vacating surface trough. High end SLGT risk
is favored for areas across Southern NM up through Central portion
of the state with the favored areas likely including the
Sacramento's, Sangre de Cristos, and areas within and surrounding
El Paso.

...Central Plains to Midwest...

Convective pattern across the Plains and Midwest at the end of the
D1 will translate northward into the Upper Mississippi Valley with
organized convection over NE/IA and SD/MN converging along the
propagating warm front leading to a swath of heavy rainfall across
much of the Southern 1/3rd of MN into Western WI. Beginning to see
the CAMs come into better agreement on the anticipated convective
evolution with a dual QPF maxima most likely situated over the area
between Aberdeen, SD to Minneapolis with a consensus on the
heaviest precip along and south of I-94 in MN with a bullseye
generally overhead or very close to Minneapolis proper. The second
maxima is positioned across Northeast NE into Northern IA to the
southern reaches of the MN border where a multi-round convective
impact forecast is being depicted in guidance as the initial round
in the morning will give way to a short break before redevelopment
occurs back along the frontal positioning bisecting the area. A
strong IVT pulse currently aligned from KS up through Eastern NE
has helped push PWATs closer to the 99th percentile around Omaha
this evening with the 00z RAOB out of KOAX depicting a PWAT of
1.94", putting this just below the daily climatological max for the
day (25/00z) and well above the 90th percentile for not just the
period, but even for the sites general historical record. This same
airmass is what's progged to advect northeast into MN and Western
WI by the time we reach tomorrow afternoon, a signal that would
prime any convective impacts to likely provide some prolific heavy
rain cores in stronger cells impacting the region. With the proxy
of the front and the environment in place, there's ample evidence
that some areas across the Midwest will see between 3-6" with the
5-6" range within reason as inferred by modest >5" neighborhood
probs (20-35%) in the latest HREF output. This same signal is
situated over the two defined maxima in guidance with the >3"
signal between 50-80% for both areas.

Considering all of the above factors and relatively good agreement
within the 00z guidance this evening, the previous SLGT risk was
maintained and leans towards a higher end risk with some prospects
of a targeted upgrade in any of those outlined forecast maxima by
the next update. Widespread significant impacts are not
anticipated at this time, but locally considerable flash flooding
is plausible in the setup. SLGT risk extends into the Western Great
Lakes on the eastern flank and down into Southern NE on the
southwest flank of the risk with potentially for widely scattered
flash flood prospects as convection impacts both areas during the
period.

...Mid Atlantic...

The northern fringe of our powerful ridge centered over the Ohio
Valley and Mid Atlantic will begin breaking down through the course
of Wednesday with an increase in PWATs likely to advect over the
area as moisture finally, "rounds the bend" over the Great Lakes
and pushes into the Northeast CONUS. Mean flow will shift more
northwesterly by the time we reach the afternoon hrs with a
significantly buoyant environment in place and generally less
capping as our ridge weakens. A few small mid-level perturbations
analyzed over the Great Lakes currently will sweep southeastward
into PA by morning and eventually cross over the region by peak
diurnal maximum. The combination of a very buoyant environment
with focused ascent will lead to scattered thunderstorm development
across much of PA, Northern WV, and into the Central Mid Atlantic
domain with sights on Southern NJ/MD/Northern VA. MUCAPE between
2500-4000 J/kg across the Central Mid Atlantic and a maxima near
5000 J/kg out in the Central Appalachians will be plentiful to help
boost convective magnitude as cells develop and mature on their
way to the southeast. Cell motion will thankfully be somewhat
progressive leading to a low prospect for training. However, PWATs
running ~2 deviations above normal (1.8-2.1") across much of the
region will certainly benefit heavy rain prospects with hourly
rates likely to settle between 1-2"/hr in any given location with
some stronger cores possibly hitting upwards of 2-3"/hr on average
with higher intra-hour rates. A MRGL risk remains in effect for
much of the Mid Atlantic with the northern periphery of the risk
area as far north as NY state with the southern edge down into
Central VA.

...Southeast...

A migrating TUTT cell off the coast of FL will continue to
propagate westward and provide favorable ascent within the proxy of
the Southeastern CONUS. Unstable airmass and large scale ascent
will aid in scattered thunderstorms developing all across the South
with the highest threat of heavy rainfall centered over Southern NC
down through Central SC into Southern GA where instability (>3000
J/kg of SBCAPE) is forecast to be highest. Heavy rainfall of
2-3"/hr is anticipated in some of the stronger convective cores
leading to isolated flash flood prospects in any urbanized
settings. Given the more focused ascent pattern provided by the
advancing TUTT, the threat sneaks into the lower end of the MRGL
risk threshold, so a broad MRGL was positioned over much of the
Southeast to cover the threat.

Kleebauer


Day 2
Valid 12Z Thu Jun 26 2025 - 12Z Fri Jun 27 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL OVER PORTIONS OF
THE CENTRAL PLAINS, MIDWEST AND NORTHERN GREAT LAKES...

...Central Plains into Great Lakes...

The final shortwave in the progression bleeding over from the
previous D1 time frame will continue pushing northeast before
finally vacating the Upper Midwest later on Thursday. Heavy rain
threat will continue over parts of MN and WI before eventually
impacting the Western U.P. of Michigan before its departure.
Instability across the region will be significantly lower than
previous days with the warm front becoming stationary prior to
reaching the southern shores of Lake Superior. The threat for flash
flooding is most notably in the first 6-12 hr window of the
forecast with a sharp decline in the threat afterwards as the
pattern shifts with the ridge expected to be breaking down. 1-2"
with locally higher amounts (upwards of 4") will allow for flash
flooding in any area from IA up through MN/WI, especially in places
where significant rainfall has occurred in prior periods. A
secondary maxima is forecast across portions of the Central Plains
down around KS/Northwest MO as a surface low over the Northern
Plains migrates eastward and drags a cold front across the Plains
and adjacent Midwestern areas. Guidance has been keying on a
secondary QPF maxima located within that corridor as thunderstorms
form along a defined instability axis with mid-level ascent
availability from a trailing shortwave over the region and some
marginal convergence ahead of the cold front to the north and
northwest. Locally 2-4" are possible in this region, an area that
has had the benefit of multiple heavy rain instances the past
48hrs. A broad SLGT risk remains in place over the Northern Great
Lakes and Upper Midwest, now extending back into parts of the
Central Plains to cover for the additional threat trailing the
surface reflection.

...New Mexico...

Isolated to scattered thunderstorms across the Sacramento's and
adjacent desert will maintain at least some threat for flash
flooding given wet antecedent conditions following previous multi-
day convective impact in prior periods. Coverage and intensity of
convection will be less than previous days as we lose the benefit
of the RER jet dynamics that have assisted in the recent days.
Still, remnant elevated moisture and sufficient buoyancy within
the confines of far West TX up through Southern and Eastern NM will
maintain a posture of diurnally driven thunderstorms with locally
heavy rainfall across the above areas. Heaviest thunderstorms will
be capable of 1-2" with the peak QPF max probably closer to 3" as
noted by modest HREF neighborhood probabilities for >3" with a
decline to 0% for >5". The previous MRGL risk was maintained and
expanded to encompass areas that will be at highest risk for flash
flooding due to the antecedent conditions and potential
thunderstorm activity.

...Mid Atlantic...

Disturbance rounding the northern periphery of our massive ridge
will ultimately slide down through the Mid Atlantic during the
mid to late-afternoon hrs. on Thursday. The combination of strong
diurnal destabilization during the daytime and prominent moisture
lingering over the area will create a very buoyant environment
capable of strong thunderstorm genesis anywhere from NY state down
through the Central Mid Atlantic including; MD/PA/DE/Northern WV
and VA. The key to this setup compared to the D1 period will be a
targeted focus within the confines of cold front pressing southward
out of the Northern Mid Atlantic Thursday afternoon and evening.
High pressure over Northern New England into Quebec will act as a
forcing mechanism to propel the front with a wedged signature
occurring east of the Appalachian front. Concern is for
thunderstorm genesis along the boundary, but a setup conducive for
eventual back-building along the front as it migrates into Northern
VA and will hit a wall in its progression. Guidance has increased
area maximum within the QPF output with some local spots seeing
2-4" over portions of the Central Mid Atlantic, mainly south of the
PA Turnpike down into the Northern Shenandoah and points east,
including the DC/Balt metro. These heavier returns will be more
isolated in coverage, but could still provide locally significant
impacts if over the wrong area. For now, have maintained the MRGL
risk, but a targeted SLGT risk could be added over parts of the
region if the signal becomes more concrete on where the heaviest
precip will align.

...Southeast...

Scattered to widely scattered thunderstorms over much of the
Southeastern CONUS will yield some heavy rainfall prospects during
the day Thursday with a decay in coverage once we lose diurnal
heating. The main areas of interest will lie along the terrain
in the Southern Appalachians and along the Gulf coast where the
remnants of a migrating TUTT cell will maintain a focal point for
heavy convective prospects during the period. Best threat for any
flash flooding will be tied to the complex topography and urban
settings where runoff capabilities are highest. Relatively modest
HREF probs for >3" (20-35%) during the 12-00z time frame on D2 are
littered over the Southeast leading to a broad MRGL risk to cover
for all the local threats. The risk lies within the lower end of
the threshold and some adjustments are possible pending CAMs
conjecture.

Kleebauer


Day 3
Valid 12Z Fri Jun 27 2025 - 12Z Sat Jun 28 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL OVER PORTIONS OF
NORTHERN NEW ENGLAND...

...Northern New England...

A strong shortwave originating from the Midwest the period prior is
forecast to cross through the Great Lakes and continue migrating
into Southeastern Canada as we enter D3. A surface low will be moving east-northeast through the Lakes into neighboring Ontario Province
by Friday afternoon which will aid in regional ascent and a
strengthening low level convergence regime tied evolving synoptic
pattern across Canada and the Northeastern U.S. Assessment of the
theta_E field signals a sharp northern gradient within the
instability regime as surface ridging downstream and warm frontal
approach on the lead side of the low will create quite a thermal
gradient across Ontario/Southern Quebec, extending into Northern
New England. This will lay the foundation for an anticipated
development of an MCS upstream over Ontario in conjunction to the
shortwave arrival and aided large scale ascent within the tail end
of a jet streak exiting over Quebec into ME. The progression of
the MCS will be important to discern as the complex will likely
spur a threat of heavy rainfall, and certainly some prospects of
back-building along the flanking side of the disturbance within the
thermal gradient outlined. Models are right on the edge in a
majority of cases for significant rains to impact NY North Country
over into Northern VT as they will be closest the complex on its
progression, and lie right along that thermal gradient in place.
Ensemble bias correction this evening is extremely bullish in its
presentation, a lot likely owed to an aggressive 00z GFS output,
but even other guidance is relatively close with some impressive
totals located along and just north of the border. ECMWF AIFS ML
guidance is right within the median outcome with the heaviest
centered right at the International border with the heaviest precip
just to the north. Given some of the sensitivities in the area over
Northern VT into North Country, and in coordination with the local
Burlington WFO, a small SLGT risk has been added over the
aforementioned area to cover for the threat. If trends for the
heavier precip end up shifting north, a removal is possible, but
considering the potential, the higher risk was added to aid
messaging and correlate with the latest ensemble means.

...Northern Plains...

A quick moving shortwave across the North-Central tier of the CONUS
will lead to scattered thunderstorm activity capable of locally
heavy rainfall and flash flood prospects. The best threat will be
over Northern ND into the Red River area where some urbanized zones
will have a greater threat for flash flooding. A quick 1-3" is
likely anywhere over Central ND into Northwest MN. This threat is
within the lower end of the MRGL risk threshold and will be
monitored closely to see if the risk is warranted, or needs any
expansion.

...West Texas into New Mexico...

Continued threat of widely scattered thunderstorms across far West
TX into NM will allow for isolated flash flood concerns over areas
that will have seen several days of heavy convective impacts with
compromised FFG's. Local 1-2" is possible in the period with the
highest threat likely over the Sacramento's down through the
Guadalupe Mtns. and adjacent valleys. A MRGL risk was maintained to
cover for the threat.

Kleebauer


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!9taZ5EAUreXnXpQnW-4SJU6AAekNav7GImddWpeFzIVY= xF_IB5TWYQFg9mQ0a43_qwJg5KRGyLK8jNN47PVwOUc4QEc$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!9taZ5EAUreXnXpQnW-4SJU6AAekNav7GImddWpeFzIVY= xF_IB5TWYQFg9mQ0a43_qwJg5KRGyLK8jNN47PVwMm_tkA4$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!9taZ5EAUreXnXpQnW-4SJU6AAekNav7GImddWpeFzIVY= xF_IB5TWYQFg9mQ0a43_qwJg5KRGyLK8jNN47PVwc7OeE2A$=20

=3D =3D =3D
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FOUS30 KWBC 252022
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
422 PM EDT Wed Jun 25 2025

Day 1
Valid 16Z Wed Jun 25 2025 - 12Z Thu Jun 26 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL OVER PORTIONS OF
NEW MEXICO, CENTRAL PLAINS AND MIDWEST...

...16Z Update...

Only minor areal modifications were made to better focus the
inherited Slight Risk areas based on the latest 12Z guidance, with
the prior forecast remaining ontrack overall. This included a
westward shift of the Slight Risk over the Upper Midwest where the
greater risk looks to be closer to the Upper Mississippi Valley
rather than eastward towards the Great Lakes. Still expect that the
higher-end threat within the Slight Risk exists in a corridor from
the central Missouri Valley northeastward towards the greater
Minneapolis area, where the greatest chance for rainfall totals of
3-4", locally 5-6", exists and may lead to more widespread
instances of flash flooding. For New Mexico/west Texas, the latest
guidance indicates that the more focused, higher-end threat within
the Slight Risk has concentrated southward over south-central New
Mexico (including the Sacramento Mountains and Ruidoso burn scar)
as well as western Texas from greater El Paso eastward through the
Guadalupe mountains. This covers the region with the greatest
potential for rainfall totals upwards of 2", locally 3".

Putnam

...Previous Discussion...

...New Mexico...

Despite a bit less areal coverage anticipated for convection
across New Mexico for Wednesday, scattered thunderstorms will still
cause problems after daytime initiation as ample heating during
the prime destabilization window (16-21z) will yield another threat
of heavy rainfall across the terrain and adjacent valleys across
NM. Main jet to the north will lift out of the area allowing for
less of a large scale ascent pattern that could maximize any
convective pattern over the region. Remnant elevated moisture
(PWATs) running between 1-2 standard deviations above normal on
the western flank of our ridge will still be located across the
state leaving an environment capable of heavy rainfall in any
convective cores that develop. Impacts the previous period were
felt over a large portion of the state leading to generally lower
FFG's bisecting much of the area expected to see a chance for
convection today. Latest HREF neighborhood probs for >3" are
running pretty high (50-70%) across places like El Paso and points
north within part of the Sacramento's, an area we have highlighted
the past several days. Modest probs (20-40%) for >3" extend all
the way up into the Sangre de Cristos with some smaller relative
mins mixed into the areal coverage. This is more a testament to the valley/terrain components littered over the state, so not all areas
will see impactful rainfall with this convective evolution.

The signal is sufficient enough to warrant a broad SLGT risk
within the state extending down through far West TX given the
current CAMs interpretation of scattered heavy convection likely to
impact portions of El Paso and Hudspeth counties through part of
the period. Some strong cells could even develop across the NM
Caprock as inferred by a few hi-res deterministic, likely due to
the favorable instability tongue positioned over the eastern side
of the state behind a vacating surface trough. High end SLGT risk
is favored for areas across Southern NM up through Central portion
of the state with the favored areas likely including the
Sacramento's, Sangre de Cristos, and areas within and surrounding
El Paso.

...Central Plains to Midwest...

Convective pattern across the Plains and Midwest at the end of the
D1 will translate northward into the Upper Mississippi Valley with
organized convection over NE/IA and SD/MN converging along the
propagating warm front leading to a swath of heavy rainfall across
much of the Southern 1/3rd of MN into Western WI. Beginning to see
the CAMs come into better agreement on the anticipated convective
evolution with a dual QPF maxima most likely situated over the area
between Aberdeen, SD to Minneapolis with a consensus on the
heaviest precip along and south of I-94 in MN with a bullseye
generally overhead or very close to Minneapolis proper. The second
maxima is positioned across Northeast NE into Northern IA to the
southern reaches of the MN border where a multi-round convective
impact forecast is being depicted in guidance as the initial round
in the morning will give way to a short break before redevelopment
occurs back along the frontal positioning bisecting the area. A
strong IVT pulse currently aligned from KS up through Eastern NE
has helped push PWATs closer to the 99th percentile around Omaha
this evening with the 00z RAOB out of KOAX depicting a PWAT of
1.94", putting this just below the daily climatological max for the
day (25/00z) and well above the 90th percentile for not just the
period, but even for the sites general historical record. This same
airmass is what's progged to advect northeast into MN and Western
WI by the time we reach tomorrow afternoon, a signal that would
prime any convective impacts to likely provide some prolific heavy
rain cores in stronger cells impacting the region. With the proxy
of the front and the environment in place, there's ample evidence
that some areas across the Midwest will see between 3-6" with the
5-6" range within reason as inferred by modest >5" neighborhood
probs (20-35%) in the latest HREF output. This same signal is
situated over the two defined maxima in guidance with the >3"
signal between 50-80% for both areas.

Considering all of the above factors and relatively good agreement
within the 00z guidance this evening, the previous SLGT risk was
maintained and leans towards a higher end risk with some prospects
of a targeted upgrade in any of those outlined forecast maxima by
the next update. Widespread significant impacts are not
anticipated at this time, but locally considerable flash flooding
is plausible in the setup. SLGT risk extends into the Western Great
Lakes on the eastern flank and down into Southern NE on the
southwest flank of the risk with potentially for widely scattered
flash flood prospects as convection impacts both areas during the
period.

...Mid Atlantic...

The northern fringe of our powerful ridge centered over the Ohio
Valley and Mid Atlantic will begin breaking down through the course
of Wednesday with an increase in PWATs likely to advect over the
area as moisture finally, "rounds the bend" over the Great Lakes
and pushes into the Northeast CONUS. Mean flow will shift more
northwesterly by the time we reach the afternoon hrs with a
significantly buoyant environment in place and generally less
capping as our ridge weakens. A few small mid-level perturbations
analyzed over the Great Lakes currently will sweep southeastward
into PA by morning and eventually cross over the region by peak
diurnal maximum. The combination of a very buoyant environment
with focused ascent will lead to scattered thunderstorm development
across much of PA, Northern WV, and into the Central Mid Atlantic
domain with sights on Southern NJ/MD/Northern VA. MUCAPE between
2500-4000 J/kg across the Central Mid Atlantic and a maxima near
5000 J/kg out in the Central Appalachians will be plentiful to help
boost convective magnitude as cells develop and mature on their
way to the southeast. Cell motion will thankfully be somewhat
progressive leading to a low prospect for training. However, PWATs
running ~2 deviations above normal (1.8-2.1") across much of the
region will certainly benefit heavy rain prospects with hourly
rates likely to settle between 1-2"/hr in any given location with
some stronger cores possibly hitting upwards of 2-3"/hr on average
with higher intra-hour rates. A MRGL risk remains in effect for
much of the Mid Atlantic with the northern periphery of the risk
area as far north as NY state with the southern edge down into
Central VA.

...Southeast...

A migrating TUTT cell off the coast of FL will continue to
propagate westward and provide favorable ascent within the proxy of
the Southeastern CONUS. Unstable airmass and large scale ascent
will aid in scattered thunderstorms developing all across the South
with the highest threat of heavy rainfall centered over Southern NC
down through Central SC into Southern GA where instability (>3000
J/kg of SBCAPE) is forecast to be highest. Heavy rainfall of
2-3"/hr is anticipated in some of the stronger convective cores
leading to isolated flash flood prospects in any urbanized
settings. Given the more focused ascent pattern provided by the
advancing TUTT, the threat sneaks into the lower end of the MRGL
risk threshold, so a broad MRGL was positioned over much of the
Southeast to cover the threat.

Kleebauer


Day 2
Valid 12Z Thu Jun 26 2025 - 12Z Fri Jun 27 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL OVER PORTIONS OF
THE CENTRAL PLAINS, MIDWEST AND NORTHERN GREAT LAKES...


...2030Z Update...

Minimal areal adjustments were made to the Slight Risk previously=20
introduced stretching from the Central Plains northeastward into=20
the Upper Midwest/Great Lakes. Newly available hi-res guidance=20
through the period matches the depicted area quite well with the=20
only changes being a reduction of coverage across portions of=20
Minnesota as storm coverage has tightened in vicinity of the warm=20
front, and a small southwest extension across south-central Kansas=20
with trailing convection along the instability axis. Locally heavy=20
rainfall totals of 2-4" remain plausible, though some of the=20
guidance tends to favor one or the other dual QPF maxima noted in=20
the prior discussion, and future runs may help either shift and/or=20
better focus the most notable potential threat area. The other area
of note is through the central Mid-Atlantic where the approach of=20
a 'backdoor' cold front may help to focus convection better than=20
during the day 1 (Wednesday) period as slow-moving storms develop=20
both ahead of the front with daytime heating as well as along the=20 approaching front. However, newly available hi-res guidance/QPF=20
indicate storms will remain widely scattered enough for now that=20
the flash flood threat should still be isolated.=20

Putnam

...Previous Discussion...


...Central Plains into Great Lakes...

The final shortwave in the progression bleeding over from the
previous D1 time frame will continue pushing northeast before
finally vacating the Upper Midwest later on Thursday. Heavy rain
threat will continue over parts of MN and WI before eventually
impacting the Western U.P. of Michigan before its departure.
Instability across the region will be significantly lower than
previous days with the warm front becoming stationary prior to
reaching the southern shores of Lake Superior. The threat for flash
flooding is most notably in the first 6-12 hr window of the
forecast with a sharp decline in the threat afterwards as the
pattern shifts with the ridge expected to be breaking down. 1-2"
with locally higher amounts (upwards of 4") will allow for flash
flooding in any area from IA up through MN/WI, especially in places
where significant rainfall has occurred in prior periods. A
secondary maxima is forecast across portions of the Central Plains
down around KS/Northwest MO as a surface low over the Northern
Plains migrates eastward and drags a cold front across the Plains
and adjacent Midwestern areas. Guidance has been keying on a
secondary QPF maxima located within that corridor as thunderstorms
form along a defined instability axis with mid-level ascent
availability from a trailing shortwave over the region and some
marginal convergence ahead of the cold front to the north and
northwest. Locally 2-4" are possible in this region, an area that
has had the benefit of multiple heavy rain instances the past
48hrs. A broad SLGT risk remains in place over the Northern Great
Lakes and Upper Midwest, now extending back into parts of the
Central Plains to cover for the additional threat trailing the
surface reflection.

...New Mexico...

Isolated to scattered thunderstorms across the Sacramento's and
adjacent desert will maintain at least some threat for flash
flooding given wet antecedent conditions following previous multi-
day convective impact in prior periods. Coverage and intensity of
convection will be less than previous days as we lose the benefit
of the RER jet dynamics that have assisted in the recent days.
Still, remnant elevated moisture and sufficient buoyancy within
the confines of far West TX up through Southern and Eastern NM will
maintain a posture of diurnally driven thunderstorms with locally
heavy rainfall across the above areas. Heaviest thunderstorms will
be capable of 1-2" with the peak QPF max probably closer to 3" as
noted by modest HREF neighborhood probabilities for >3" with a
decline to 0% for >5". The previous MRGL risk was maintained and
expanded to encompass areas that will be at highest risk for flash
flooding due to the antecedent conditions and potential
thunderstorm activity.

...Mid Atlantic...

Disturbance rounding the northern periphery of our massive ridge
will ultimately slide down through the Mid Atlantic during the
mid to late-afternoon hrs. on Thursday. The combination of strong
diurnal destabilization during the daytime and prominent moisture
lingering over the area will create a very buoyant environment
capable of strong thunderstorm genesis anywhere from NY state down
through the Central Mid Atlantic including; MD/PA/DE/Northern WV
and VA. The key to this setup compared to the D1 period will be a
targeted focus within the confines of cold front pressing southward
out of the Northern Mid Atlantic Thursday afternoon and evening.
High pressure over Northern New England into Quebec will act as a
forcing mechanism to propel the front with a wedged signature
occurring east of the Appalachian front. Concern is for
thunderstorm genesis along the boundary, but a setup conducive for
eventual back-building along the front as it migrates into Northern
VA and will hit a wall in its progression. Guidance has increased
area maximum within the QPF output with some local spots seeing
2-4" over portions of the Central Mid Atlantic, mainly south of the
PA Turnpike down into the Northern Shenandoah and points east,
including the DC/Balt metro. These heavier returns will be more
isolated in coverage, but could still provide locally significant
impacts if over the wrong area. For now, have maintained the MRGL
risk, but a targeted SLGT risk could be added over parts of the
region if the signal becomes more concrete on where the heaviest
precip will align.

...Southeast...

Scattered to widely scattered thunderstorms over much of the
Southeastern CONUS will yield some heavy rainfall prospects during
the day Thursday with a decay in coverage once we lose diurnal
heating. The main areas of interest will lie along the terrain
in the Southern Appalachians and along the Gulf coast where the
remnants of a migrating TUTT cell will maintain a focal point for
heavy convective prospects during the period. Best threat for any
flash flooding will be tied to the complex topography and urban
settings where runoff capabilities are highest. Relatively modest
HREF probs for >3" (20-35%) during the 12-00z time frame on D2 are
littered over the Southeast leading to a broad MRGL risk to cover
for all the local threats. The risk lies within the lower end of
the threshold and some adjustments are possible pending CAMs
conjecture.

Kleebauer


Day 3
Valid 12Z Fri Jun 27 2025 - 12Z Sat Jun 28 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL OVER PORTIONS OF
NORTHERN NEW ENGLAND...

...2030Z Update...

The forecast for a focused corridor of heavy rainfall associated=20
with an MCS and trailing convection crossing from southeastern=20
Canada into portions of Update New York/northern New England=20
remains on track. While there are expectedly some variances on the=20
possible MCS path which add some east-west uncertainty, all=20
guidance is still in good agreement that the track will clip areas=20
south of the international border bringing an attendant flash flood
threat. Deterministic guidance indicates the potential of rainfall
totals between 2-4", with ensemble probabilities of 2"+ between=20
25-35%. A modest eastward adjustment of the Slight Risk area was=20
added based on these latest ensemble probabilities. Elsewhere,=20
prior forecast has remained consistent.=20

Putnam

...Previous Discussion...

...Northern New England...

A strong shortwave originating from the Midwest the period prior is
forecast to cross through the Great Lakes and continue migrating
into Southeastern Canada as we enter D3. A surface low will be moving east-northeast through the Lakes into neighboring Ontario Province
by Friday afternoon which will aid in regional ascent and a
strengthening low level convergence regime tied evolving synoptic
pattern across Canada and the Northeastern U.S. Assessment of the
theta_E field signals a sharp northern gradient within the
instability regime as surface ridging downstream and warm frontal
approach on the lead side of the low will create quite a thermal
gradient across Ontario/Southern Quebec, extending into Northern
New England. This will lay the foundation for an anticipated
development of an MCS upstream over Ontario in conjunction to the
shortwave arrival and aided large scale ascent within the tail end
of a jet streak exiting over Quebec into ME. The progression of
the MCS will be important to discern as the complex will likely
spur a threat of heavy rainfall, and certainly some prospects of
back-building along the flanking side of the disturbance within the
thermal gradient outlined. Models are right on the edge in a
majority of cases for significant rains to impact NY North Country
over into Northern VT as they will be closest the complex on its
progression, and lie right along that thermal gradient in place.
Ensemble bias correction this evening is extremely bullish in its
presentation, a lot likely owed to an aggressive 00z GFS output,
but even other guidance is relatively close with some impressive
totals located along and just north of the border. ECMWF AIFS ML
guidance is right within the median outcome with the heaviest
centered right at the International border with the heaviest precip
just to the north. Given some of the sensitivities in the area over
Northern VT into North Country, and in coordination with the local
Burlington WFO, a small SLGT risk has been added over the
aforementioned area to cover for the threat. If trends for the
heavier precip end up shifting north, a removal is possible, but
considering the potential, the higher risk was added to aid
messaging and correlate with the latest ensemble means.

...Northern Plains...

A quick moving shortwave across the North-Central tier of the CONUS
will lead to scattered thunderstorm activity capable of locally
heavy rainfall and flash flood prospects. The best threat will be
over Northern ND into the Red River area where some urbanized zones
will have a greater threat for flash flooding. A quick 1-3" is
likely anywhere over Central ND into Northwest MN. This threat is
within the lower end of the MRGL risk threshold and will be
monitored closely to see if the risk is warranted, or needs any
expansion.

...West Texas into New Mexico...

Continued threat of widely scattered thunderstorms across far West
TX into NM will allow for isolated flash flood concerns over areas
that will have seen several days of heavy convective impacts with
compromised FFG's. Local 1-2" is possible in the period with the
highest threat likely over the Sacramento's down through the
Guadalupe Mtns. and adjacent valleys. A MRGL risk was maintained to
cover for the threat.

Kleebauer


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!5bm9UFxeuXcRZGDGZdOT3wByZ80SwBP2O5ryyToT3hNh= IbJSxlann4zDBmKS8R0AqdnbNRl23Be3C7U7hfzWWHJ9kRE$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!5bm9UFxeuXcRZGDGZdOT3wByZ80SwBP2O5ryyToT3hNh= IbJSxlann4zDBmKS8R0AqdnbNRl23Be3C7U7hfzWyRTy7Ms$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!5bm9UFxeuXcRZGDGZdOT3wByZ80SwBP2O5ryyToT3hNh= IbJSxlann4zDBmKS8R0AqdnbNRl23Be3C7U7hfzWsyqOeCs$=20

=3D =3D =3D
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FOUS30 KWBC 260057
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
857 PM EDT Wed Jun 25 2025

Day 1
Valid 01Z Thu Jun 26 2025 - 12Z Thu Jun 26 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL OVER PORTIONS OF
NEW MEXICO, CENTRAL PLAINS, AND MIDWEST...

...01Z Update...

With much of the Marginal Risk areas largely driven by diurnal
heating, the areas were shrunken down noticeably in the East and=20
in on the northern flank of the Marginal Risk area in the Upper=20
Midwest. The Slight Risk in the Upper Midwest was also trimmed back
on the northern flank as the best instability and forcing now lies
from central Nebraska on east across the Missouri River and into=20
eastern Iowa. The Slight Risk there was adjusted to account for new
18Z HREF probabilistic guidance, but the meteorological rationale=20
for supporting the Slight Risk into tonight remains on track. ECMWF
SATs for 06Z tonight show a ribbon of >99.5 climatological=20
percentile PWATs from the central NE/KS border that extends east=20
through southern MN and central WI. The Slight Risk area is also=20
likely to have as much as 1,000 J/kg of MUCAPE at its disposal=20
as a steadfast 30-40kt LLJ runs parallel to a nearby surface=20
trough. The Slight Risk was maintained in southern NM and far=20
western TX given the lingering thunderstorm activity will last a=20
little longer than the storms in the East. Lingering instability=20
and anomalous moisture may keep storms deeper into the evening=20
hours as a result.

---Previous Discussion---

...16Z Update...

Only minor areal modifications were made to better focus the
inherited Slight Risk areas based on the latest 12Z guidance, with
the prior forecast remaining ontrack overall. This included a
westward shift of the Slight Risk over the Upper Midwest where the
greater risk looks to be closer to the Upper Mississippi Valley
rather than eastward towards the Great Lakes. Still expect that the
higher-end threat within the Slight Risk exists in a corridor from
the central Missouri Valley northeastward towards the greater
Minneapolis area, where the greatest chance for rainfall totals of
3-4", locally 5-6", exists and may lead to more widespread
instances of flash flooding. For New Mexico/west Texas, the latest
guidance indicates that the more focused, higher-end threat within
the Slight Risk has concentrated southward over south-central New
Mexico (including the Sacramento Mountains and Ruidoso burn scar)
as well as western Texas from greater El Paso eastward through the
Guadalupe mountains. This covers the region with the greatest
potential for rainfall totals upwards of 2", locally 3".

Putnam

---Overnight Discussion---

...New Mexico...

Despite a bit less areal coverage anticipated for convection
across New Mexico for Wednesday, scattered thunderstorms will still
cause problems after daytime initiation as ample heating during
the prime destabilization window (16-21z) will yield another threat
of heavy rainfall across the terrain and adjacent valleys across
NM. Main jet to the north will lift out of the area allowing for
less of a large scale ascent pattern that could maximize any
convective pattern over the region. Remnant elevated moisture
(PWATs) running between 1-2 standard deviations above normal on
the western flank of our ridge will still be located across the
state leaving an environment capable of heavy rainfall in any
convective cores that develop. Impacts the previous period were
felt over a large portion of the state leading to generally lower
FFG's bisecting much of the area expected to see a chance for
convection today. Latest HREF neighborhood probs for >3" are
running pretty high (50-70%) across places like El Paso and points
north within part of the Sacramento's, an area we have highlighted
the past several days. Modest probs (20-40%) for >3" extend all
the way up into the Sangre de Cristos with some smaller relative
mins mixed into the areal coverage. This is more a testament to the valley/terrain components littered over the state, so not all areas
will see impactful rainfall with this convective evolution.

The signal is sufficient enough to warrant a broad SLGT risk
within the state extending down through far West TX given the
current CAMs interpretation of scattered heavy convection likely to
impact portions of El Paso and Hudspeth counties through part of
the period. Some strong cells could even develop across the NM
Caprock as inferred by a few hi-res deterministic, likely due to
the favorable instability tongue positioned over the eastern side
of the state behind a vacating surface trough. High end SLGT risk
is favored for areas across Southern NM up through Central portion
of the state with the favored areas likely including the
Sacramento's, Sangre de Cristos, and areas within and surrounding
El Paso.

...Central Plains to Midwest...

Convective pattern across the Plains and Midwest at the end of the
D1 will translate northward into the Upper Mississippi Valley with
organized convection over NE/IA and SD/MN converging along the
propagating warm front leading to a swath of heavy rainfall across
much of the Southern 1/3rd of MN into Western WI. Beginning to see
the CAMs come into better agreement on the anticipated convective
evolution with a dual QPF maxima most likely situated over the area
between Aberdeen, SD to Minneapolis with a consensus on the
heaviest precip along and south of I-94 in MN with a bullseye
generally overhead or very close to Minneapolis proper. The second
maxima is positioned across Northeast NE into Northern IA to the
southern reaches of the MN border where a multi-round convective
impact forecast is being depicted in guidance as the initial round
in the morning will give way to a short break before redevelopment
occurs back along the frontal positioning bisecting the area. A
strong IVT pulse currently aligned from KS up through Eastern NE
has helped push PWATs closer to the 99th percentile around Omaha
this evening with the 00z RAOB out of KOAX depicting a PWAT of
1.94", putting this just below the daily climatological max for the
day (25/00z) and well above the 90th percentile for not just the
period, but even for the sites general historical record. This same
airmass is what's progged to advect northeast into MN and Western
WI by the time we reach tomorrow afternoon, a signal that would
prime any convective impacts to likely provide some prolific heavy
rain cores in stronger cells impacting the region. With the proxy
of the front and the environment in place, there's ample evidence
that some areas across the Midwest will see between 3-6" with the
5-6" range within reason as inferred by modest >5" neighborhood
probs (20-35%) in the latest HREF output. This same signal is
situated over the two defined maxima in guidance with the >3"
signal between 50-80% for both areas.

Considering all of the above factors and relatively good agreement
within the 00z guidance this evening, the previous SLGT risk was
maintained and leans towards a higher end risk with some prospects
of a targeted upgrade in any of those outlined forecast maxima by
the next update. Widespread significant impacts are not
anticipated at this time, but locally considerable flash flooding
is plausible in the setup. SLGT risk extends into the Western Great
Lakes on the eastern flank and down into Southern NE on the
southwest flank of the risk with potentially for widely scattered
flash flood prospects as convection impacts both areas during the
period.

...Mid Atlantic...

The northern fringe of our powerful ridge centered over the Ohio
Valley and Mid Atlantic will begin breaking down through the course
of Wednesday with an increase in PWATs likely to advect over the
area as moisture finally, "rounds the bend" over the Great Lakes
and pushes into the Northeast CONUS. Mean flow will shift more
northwesterly by the time we reach the afternoon hrs with a
significantly buoyant environment in place and generally less
capping as our ridge weakens. A few small mid-level perturbations
analyzed over the Great Lakes currently will sweep southeastward
into PA by morning and eventually cross over the region by peak
diurnal maximum. The combination of a very buoyant environment
with focused ascent will lead to scattered thunderstorm development
across much of PA, Northern WV, and into the Central Mid Atlantic
domain with sights on Southern NJ/MD/Northern VA. MUCAPE between
2500-4000 J/kg across the Central Mid Atlantic and a maxima near
5000 J/kg out in the Central Appalachians will be plentiful to help
boost convective magnitude as cells develop and mature on their
way to the southeast. Cell motion will thankfully be somewhat
progressive leading to a low prospect for training. However, PWATs
running ~2 deviations above normal (1.8-2.1") across much of the
region will certainly benefit heavy rain prospects with hourly
rates likely to settle between 1-2"/hr in any given location with
some stronger cores possibly hitting upwards of 2-3"/hr on average
with higher intra-hour rates. A MRGL risk remains in effect for
much of the Mid Atlantic with the northern periphery of the risk
area as far north as NY state with the southern edge down into
Central VA.

...Southeast...

A migrating TUTT cell off the coast of FL will continue to
propagate westward and provide favorable ascent within the proxy of
the Southeastern CONUS. Unstable airmass and large scale ascent
will aid in scattered thunderstorms developing all across the South
with the highest threat of heavy rainfall centered over Southern NC
down through Central SC into Southern GA where instability (>3000
J/kg of SBCAPE) is forecast to be highest. Heavy rainfall of
2-3"/hr is anticipated in some of the stronger convective cores
leading to isolated flash flood prospects in any urbanized
settings. Given the more focused ascent pattern provided by the
advancing TUTT, the threat sneaks into the lower end of the MRGL
risk threshold, so a broad MRGL was positioned over much of the
Southeast to cover the threat.

Kleebauer


Day 2
Valid 12Z Thu Jun 26 2025 - 12Z Fri Jun 27 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL OVER PORTIONS OF
THE CENTRAL PLAINS, MIDWEST AND NORTHERN GREAT LAKES...


...2030Z Update...

Minimal areal adjustments were made to the Slight Risk previously
introduced stretching from the Central Plains northeastward into
the Upper Midwest/Great Lakes. Newly available hi-res guidance
through the period matches the depicted area quite well with the
only changes being a reduction of coverage across portions of
Minnesota as storm coverage has tightened in vicinity of the warm
front, and a small southwest extension across south-central Kansas
with trailing convection along the instability axis. Locally heavy
rainfall totals of 2-4" remain plausible, though some of the
guidance tends to favor one or the other dual QPF maxima noted in
the prior discussion, and future runs may help either shift and/or
better focus the most notable potential threat area. The other area
of note is through the central Mid-Atlantic where the approach of
a 'backdoor' cold front may help to focus convection better than
during the day 1 (Wednesday) period as slow-moving storms develop
both ahead of the front with daytime heating as well as along the
approaching front. However, newly available hi-res guidance/QPF
indicate storms will remain widely scattered enough for now that
the flash flood threat should still be isolated.

Putnam

...Previous Discussion...


...Central Plains into Great Lakes...

The final shortwave in the progression bleeding over from the
previous D1 time frame will continue pushing northeast before
finally vacating the Upper Midwest later on Thursday. Heavy rain
threat will continue over parts of MN and WI before eventually
impacting the Western U.P. of Michigan before its departure.
Instability across the region will be significantly lower than
previous days with the warm front becoming stationary prior to
reaching the southern shores of Lake Superior. The threat for flash
flooding is most notably in the first 6-12 hr window of the
forecast with a sharp decline in the threat afterwards as the
pattern shifts with the ridge expected to be breaking down. 1-2"
with locally higher amounts (upwards of 4") will allow for flash
flooding in any area from IA up through MN/WI, especially in places
where significant rainfall has occurred in prior periods. A
secondary maxima is forecast across portions of the Central Plains
down around KS/Northwest MO as a surface low over the Northern
Plains migrates eastward and drags a cold front across the Plains
and adjacent Midwestern areas. Guidance has been keying on a
secondary QPF maxima located within that corridor as thunderstorms
form along a defined instability axis with mid-level ascent
availability from a trailing shortwave over the region and some
marginal convergence ahead of the cold front to the north and
northwest. Locally 2-4" are possible in this region, an area that
has had the benefit of multiple heavy rain instances the past
48hrs. A broad SLGT risk remains in place over the Northern Great
Lakes and Upper Midwest, now extending back into parts of the
Central Plains to cover for the additional threat trailing the
surface reflection.

...New Mexico...

Isolated to scattered thunderstorms across the Sacramento's and
adjacent desert will maintain at least some threat for flash
flooding given wet antecedent conditions following previous multi-
day convective impact in prior periods. Coverage and intensity of
convection will be less than previous days as we lose the benefit
of the RER jet dynamics that have assisted in the recent days.
Still, remnant elevated moisture and sufficient buoyancy within
the confines of far West TX up through Southern and Eastern NM will
maintain a posture of diurnally driven thunderstorms with locally
heavy rainfall across the above areas. Heaviest thunderstorms will
be capable of 1-2" with the peak QPF max probably closer to 3" as
noted by modest HREF neighborhood probabilities for >3" with a
decline to 0% for >5". The previous MRGL risk was maintained and
expanded to encompass areas that will be at highest risk for flash
flooding due to the antecedent conditions and potential
thunderstorm activity.

...Mid Atlantic...

Disturbance rounding the northern periphery of our massive ridge
will ultimately slide down through the Mid Atlantic during the
mid to late-afternoon hrs. on Thursday. The combination of strong
diurnal destabilization during the daytime and prominent moisture
lingering over the area will create a very buoyant environment
capable of strong thunderstorm genesis anywhere from NY state down
through the Central Mid Atlantic including; MD/PA/DE/Northern WV
and VA. The key to this setup compared to the D1 period will be a
targeted focus within the confines of cold front pressing southward
out of the Northern Mid Atlantic Thursday afternoon and evening.
High pressure over Northern New England into Quebec will act as a
forcing mechanism to propel the front with a wedged signature
occurring east of the Appalachian front. Concern is for
thunderstorm genesis along the boundary, but a setup conducive for
eventual back-building along the front as it migrates into Northern
VA and will hit a wall in its progression. Guidance has increased
area maximum within the QPF output with some local spots seeing
2-4" over portions of the Central Mid Atlantic, mainly south of the
PA Turnpike down into the Northern Shenandoah and points east,
including the DC/Balt metro. These heavier returns will be more
isolated in coverage, but could still provide locally significant
impacts if over the wrong area. For now, have maintained the MRGL
risk, but a targeted SLGT risk could be added over parts of the
region if the signal becomes more concrete on where the heaviest
precip will align.

...Southeast...

Scattered to widely scattered thunderstorms over much of the
Southeastern CONUS will yield some heavy rainfall prospects during
the day Thursday with a decay in coverage once we lose diurnal
heating. The main areas of interest will lie along the terrain
in the Southern Appalachians and along the Gulf coast where the
remnants of a migrating TUTT cell will maintain a focal point for
heavy convective prospects during the period. Best threat for any
flash flooding will be tied to the complex topography and urban
settings where runoff capabilities are highest. Relatively modest
HREF probs for >3" (20-35%) during the 12-00z time frame on D2 are
littered over the Southeast leading to a broad MRGL risk to cover
for all the local threats. The risk lies within the lower end of
the threshold and some adjustments are possible pending CAMs
conjecture.

Kleebauer


Day 3
Valid 12Z Fri Jun 27 2025 - 12Z Sat Jun 28 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL OVER PORTIONS OF
NORTHERN NEW ENGLAND...

...2030Z Update...

The forecast for a focused corridor of heavy rainfall associated
with an MCS and trailing convection crossing from southeastern
Canada into portions of Update New York/northern New England
remains on track. While there are expectedly some variances on the
possible MCS path which add some east-west uncertainty, all
guidance is still in good agreement that the track will clip areas
south of the international border bringing an attendant flash flood
threat. Deterministic guidance indicates the potential of rainfall
totals between 2-4", with ensemble probabilities of 2"+ between
25-35%. A modest eastward adjustment of the Slight Risk area was
added based on these latest ensemble probabilities. Elsewhere,
prior forecast has remained consistent.

Putnam

...Previous Discussion...

...Northern New England...

A strong shortwave originating from the Midwest the period prior is
forecast to cross through the Great Lakes and continue migrating
into Southeastern Canada as we enter D3. A surface low will be moving east-northeast through the Lakes into neighboring Ontario Province
by Friday afternoon which will aid in regional ascent and a
strengthening low level convergence regime tied evolving synoptic
pattern across Canada and the Northeastern U.S. Assessment of the
theta_E field signals a sharp northern gradient within the
instability regime as surface ridging downstream and warm frontal
approach on the lead side of the low will create quite a thermal
gradient across Ontario/Southern Quebec, extending into Northern
New England. This will lay the foundation for an anticipated
development of an MCS upstream over Ontario in conjunction to the
shortwave arrival and aided large scale ascent within the tail end
of a jet streak exiting over Quebec into ME. The progression of
the MCS will be important to discern as the complex will likely
spur a threat of heavy rainfall, and certainly some prospects of
back-building along the flanking side of the disturbance within the
thermal gradient outlined. Models are right on the edge in a
majority of cases for significant rains to impact NY North Country
over into Northern VT as they will be closest the complex on its
progression, and lie right along that thermal gradient in place.
Ensemble bias correction this evening is extremely bullish in its
presentation, a lot likely owed to an aggressive 00z GFS output,
but even other guidance is relatively close with some impressive
totals located along and just north of the border. ECMWF AIFS ML
guidance is right within the median outcome with the heaviest
centered right at the International border with the heaviest precip
just to the north. Given some of the sensitivities in the area over
Northern VT into North Country, and in coordination with the local
Burlington WFO, a small SLGT risk has been added over the
aforementioned area to cover for the threat. If trends for the
heavier precip end up shifting north, a removal is possible, but
considering the potential, the higher risk was added to aid
messaging and correlate with the latest ensemble means.

...Northern Plains...

A quick moving shortwave across the North-Central tier of the CONUS
will lead to scattered thunderstorm activity capable of locally
heavy rainfall and flash flood prospects. The best threat will be
over Northern ND into the Red River area where some urbanized zones
will have a greater threat for flash flooding. A quick 1-3" is
likely anywhere over Central ND into Northwest MN. This threat is
within the lower end of the MRGL risk threshold and will be
monitored closely to see if the risk is warranted, or needs any
expansion.

...West Texas into New Mexico...

Continued threat of widely scattered thunderstorms across far West
TX into NM will allow for isolated flash flood concerns over areas
that will have seen several days of heavy convective impacts with
compromised FFG's. Local 1-2" is possible in the period with the
highest threat likely over the Sacramento's down through the
Guadalupe Mtns. and adjacent valleys. A MRGL risk was maintained to
cover for the threat.

Kleebauer


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!94NpJ_Tk0TqhtI7WAOFqFqN7NgIIGu5Nj6zoyzDQRwEx= btswOVwc9XldaP-f2uPMiU9mJV0eHOoMejUGrOUh1Lk0J9c$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!94NpJ_Tk0TqhtI7WAOFqFqN7NgIIGu5Nj6zoyzDQRwEx= btswOVwc9XldaP-f2uPMiU9mJV0eHOoMejUGrOUh4me5-ZE$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!94NpJ_Tk0TqhtI7WAOFqFqN7NgIIGu5Nj6zoyzDQRwEx= btswOVwc9XldaP-f2uPMiU9mJV0eHOoMejUGrOUhwyX1cHU$=20

=3D =3D =3D
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FOUS30 KWBC 260827
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
427 AM EDT Thu Jun 26 2025

Day 1
Valid 12Z Thu Jun 26 2025 - 12Z Fri Jun 27 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PARTS OF=20
THE CENTRAL PLAINS, UPPER MIDWEST, AND UPPER GREAT LAKES, ALONG=20
WITH NORTHERN PORTIONS OF THE MID ATLANTIC...

...Central Plains into the Upper Great Lakes...

Upper shortwave trough across the Northern Plains early Thu will
pivot eastward across the Upper MS Valley and Upper Great Lakes
region later Thu and Thu night. Enhancing the deep-layer forcing
will be the curved 90kt upper level jet streak that will be=20
skirting the U.S.-Canadian border. Ahead of the upper shortwave=20 trough/surface front -- 850-700 mb moisture flux anomalies are=20
noteworthy (1.5-2.0 standard deviations above normal), as is the=20
0-6km bulk shear values (35-45+ kts). This will likely support more
widespread, organized convective line segments later this=20
afternoon/evening and into the overnight across the elongated=20
Slight Risk area. Compared to yesterday's Day 2 ERO, based on the=20
latest guidance trends we did nudge the Slight slightly farther=20
east across northwest MO and southeast IA. The 00Z CAMs show 24hr=20
max QPF generally in the 3-5" range within the Slight Risk area,=20
which is supported by the HREF and RRFS 24hr QPF probabilities.=20
Multiple CAMs (including the 00Z RRFS) show isolated totals=20
exceeding 5" across eastern KS.

...Mid Atlantic...

Most of the CAMs show more widespread slow-moving convective=20
clusters within a newly-hoisted Slight area, initiating along the=20
lee-side trough and quasi-stationary, backdoor front. Relatively light (generally 20kt or less) deep-layer shear would suggest pulse-=20
type durations for the heaviest rains, but nevertheless both the=20
HREF and RRFS do show pockets of elevated probabilities with >2"/hr
rainfall rates by mid-late afternoon into Thu evening. This given=20
the favorable thermodynamic profile (1.75-2.00" PWs and max CAPEs=20
2000-3000 J/Kg, the likelihood of slow cell motions with the
potential for repetitive convection along these boundaries would
support a low-end Slight Risk, despite the lack of strong synoptic/
kinematic support.

...Parts of the Lower MS Valley, TN Valley, and Southeast...

Scattered to widely scattered thunderstorms over much of the
south-central to southeastern CONUS will yield some heavy rainfall
prospects during the day Thursday with a decay in coverage once we
lose diurnal heating. The main areas of interest will lie along=20
the terrain in the Southern Appalachians and along the Gulf coast=20
where the remnants of a migrating TUTT cell will maintain a focal=20
point for heavy convective prospects during the period. Best threat
for any flash flooding will be tied to the complex topography and=20
urban settings where runoff capabilities are highest. Relatively=20
modest HREF probs for >3" (40-60%) were noted across portions of
MS/LA and especially along the west coast of the FL Peninsula. For
now the risk appears to be a 'high end' Marginal, i.e. mainly an
isolated flash flood risk, largely due to the pulse/short-fused
nature of the more intense rainfall rates and relatively high FFG
values.=20

...New Mexico...

Isolated to scattered thunderstorms across the Sacramento's and
adjacent desert will maintain at least some threat for flash
flooding given wet antecedent conditions following previous multi-
day convective impact in prior periods. Coverage and intensity of
convection will be less than previous days as we lose the benefit
of the RER jet dynamics that have assisted in the recent days.
Still, remnant elevated moisture and sufficient buoyancy within
the confines of far West TX up through Southern and Eastern NM will
maintain a posture of diurnally driven thunderstorms with locally
heavy rainfall across the above areas. Heaviest thunderstorms will
be capable of 1-2" with the peak QPF max probably closer to 3" as
noted by modest HREF neighborhood probabilities for >3" with a
decline to 0% for >5". The previous MRGL risk was maintained.=20

Hurley


Day 2
Valid 12Z Fri Jun 27 2025 - 12Z Sat Jun 28 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL OVER PORTIONS OF
NORTHERN NEW YORK AND NORTHERN NEW ENGLAND...

...Northern NY-New England...

The forecast for a focused corridor of heavy rainfall associated
with an MCS and trailing convection crossing from southeastern
Canada into portions of Update New York/northern New England
remains on track. While there are expectedly some variances on the
possible MCS path which add some east-west uncertainty, all
guidance is still in good agreement that the track will clip areas
south of the international border bringing an attendant flash flood
threat. Deterministic guidance indicates the potential of rainfall
totals between 1-3", with ensemble probabilities of 2"+ between=20
15-25%. A small eastward adjustment of the Slight Risk area was=20
added based on these latest ensemble probabilities. Elsewhere,=20
prior forecast has remained consistent.

...Northern Plains...

A quick moving shortwave across the North-Central tier of the CONUS
will lead to scattered thunderstorm activity capable of locally
heavy rainfall and flash flood prospects. The best threat will be
over Northern ND into the Red River area where some urbanized zones
will have a greater threat for flash flooding. A quick 1-3+" is
likely anywhere over Central ND into Northwest MN. This threat is
within the lower end of the MRGL risk threshold and will be
monitored closely to see if the risk is warranted, or needs any
expansion.

...West Texas into New Mexico...

Continued threat of widely scattered thunderstorms across far West
TX into NM will allow for isolated flash flood concerns over areas
that will have seen several days of heavy convective impacts with
compromised FFG's. Local 1-2" is possible in the period with the
highest threat likely over the Sacramento's down through the
Guadalupe Mtns. and adjacent valleys. A MRGL risk was maintained to
cover for the threat.


Day 3
Valid 12Z Sat Jun 28 2025 - 12Z Sun Jun 29 2025

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS=20
OF THE NORTHERN PLAINS AND UPPER MIDWEST, THE NORTHEAST, AND
SOUTH-CENTRAL NEW MEXICO...=20

...Northern Plains and Upper Midwest...

Next approaching upper shortwave trough, with a 90kt upper level
jet streak on the lee side, will generate a compact area of fairly
robust, transient deep-layer forcing over the outlook area later in
the period (especially Sat night). MUCAPEs are expected to soar
within the warm sector prior to the surface cold frontal passage --
i.e. aoa 4,000 J/Kg per the GFS. This along with PWs getting near
1.75" will lead to more organized, widespread convection by
Saturday night as the activity likely grows upscale with the
increasing pre-frontal low-level inflow (30-40kts at 850 mb). The
00Z guidance indicates significant latitudinal spread in the
heavier QPF, and as a result, have maintained the Marginal Risk
from yesterday's Day 4 ERO. However, the potential for an upgrade
to Slight is certainly plausible given the kinematic and
thermodynamic profile, especially after 00Z Sun when the Corfidi
Vectors decrease to 10kt or less (thereby enhancing the risk for
cell training).

...Northeast...

Upper shortwave trough pushes across the Northeast by late Sat,
then off the coast Sun morning. The bulk of the rainfall will fall
during the first half of the period (during the day Sat),
coinciding with the most favorable pre-frontal deep-layer
instability and moisture (PWs 1.75-2.00+ inches). The 00Z guidance
shows considerable spread with the heaviest QPF, though are fairly
similar with the max totals (1.5-3.0"). Given the spread in the
model QPFs, along with the progression of the front and fairly=20
quick diminishment in instability after 00Z Sun, for now will
maintain the Marginal Risk.

...New Mexico...

Maintained a targeted Marginal Risk area over/near the Sacramento
Mtns, particularly the burn scar areas from the 2024 fires (Blue 2,
South Fork, and Salt burn scars). QPF trends (coverage, intensity)
are similar to Day 2, with the moist S-SE low-level upslope flow
likely resulting in a concentrated area of heavier rainfall across
the Sacramento Mtns and eastern foothills. The flash flood
potential is expected to remain isolated/localized.

Hurley


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!4yNY3jE25Pwj9CTEBZPB9dy3HesWJrjXwJZRAYxHr5m9= 8RZfTAUaRHMOFphPlc1rZ9vvvJfiIKz4dN_EmSlf6FhZDdM$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!4yNY3jE25Pwj9CTEBZPB9dy3HesWJrjXwJZRAYxHr5m9= 8RZfTAUaRHMOFphPlc1rZ9vvvJfiIKz4dN_EmSlfP4MWaAM$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!4yNY3jE25Pwj9CTEBZPB9dy3HesWJrjXwJZRAYxHr5m9= 8RZfTAUaRHMOFphPlc1rZ9vvvJfiIKz4dN_EmSlfMw4sCj0$=20

=3D =3D =3D
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FOUS30 KWBC 260849
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
449 AM EDT Thu Jun 26 2025

Day 1
Valid 12Z Thu Jun 26 2025 - 12Z Fri Jun 27 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PARTS OF
THE CENTRAL PLAINS, UPPER MIDWEST, AND UPPER GREAT LAKES, ALONG
WITH NORTHERN PORTIONS OF THE MID ATLANTIC...

...Central Plains into the Upper Great Lakes...

Upper shortwave trough across the Northern Plains early Thu will
pivot eastward across the Upper MS Valley and Upper Great Lakes
region later Thu and Thu night. Enhancing the deep-layer forcing
will be the curved 90kt upper level jet streak that will be
skirting the U.S.-Canadian border. Ahead of the upper shortwave
trough/surface front -- 850-700 mb moisture flux anomalies are
noteworthy (1.5-2.0 standard deviations above normal), as is the
0-6km bulk shear values (35-45+ kts). This will likely support more
widespread, organized convective line segments later this
afternoon/evening and into the overnight across the elongated
Slight Risk area. Compared to yesterday's Day 2 ERO, based on the
latest guidance trends we did nudge the Slight slightly farther
east across northwest MO and southeast IA. The 00Z CAMs show 24hr
max QPF generally in the 3-5" range within the Slight Risk area,
which is supported by the HREF and RRFS 24hr QPF probabilities.
Multiple CAMs (including the 00Z RRFS) show isolated totals
exceeding 5" across eastern KS.

...Mid Atlantic...

Most of the CAMs show more widespread slow-moving convective
clusters within a newly-hoisted Slight area, initiating along the
lee-side trough and quasi-stationary, backdoor front. Relatively light (generally 20kt or less) deep-layer shear would suggest pulse-
type durations for the heaviest rains, but nevertheless both the
HREF and RRFS do show pockets of elevated probabilities with >2"/hr
rainfall rates by mid-late afternoon into Thu evening. Therefore=20
given the favorable thermodynamic profile (1.75-2.00" PWs and max=20
CAPEs 2000-3000 J/Kg), the likelihood of slow cell motions with the
potential for repetitive convection along these boundaries would=20
support a low-end Slight Risk across the northern Mid Atlantic
(northern VA into eastern MD and Eastern PA), despite the lack of=20
strong synoptic/ kinematic support.

...Parts of the Lower MS Valley, TN Valley, and Southeast...

Scattered to widely scattered thunderstorms over much of the
south-central to southeastern CONUS will yield some heavy rainfall
prospects during the day Thursday with a decay in coverage once we
lose diurnal heating. The main areas of interest will lie along
the terrain in the Southern Appalachians and along the Gulf coast
where the remnants of a migrating TUTT cell will maintain a focal
point for heavy convective prospects during the period. Best threat
for any flash flooding will be tied to the complex topography and
urban settings where runoff capabilities are highest. Relatively
modest HREF probs for >3" (40-60%) were noted across portions of
MS/LA and especially along the west coast of the FL Peninsula. For
now the risk appears to be a 'high end' Marginal, i.e. mainly an
isolated flash flood risk, largely due to the pulse/short-fused
nature of the more intense rainfall rates and relatively high FFG
values.

...New Mexico...

Isolated to scattered thunderstorms across the Sacramento's and
adjacent desert will maintain at least some threat for flash
flooding given wet antecedent conditions following previous multi-
day convective impact in prior periods. Coverage and intensity of
convection will be less than previous days as we lose the benefit
of the RER jet dynamics that have assisted in the recent days.
Still, remnant elevated moisture and sufficient buoyancy within
the confines of far West TX up through Southern and Eastern NM will
maintain a posture of diurnally driven thunderstorms with locally
heavy rainfall across the above areas. Heaviest thunderstorms will
be capable of 1-2" with the peak QPF max probably closer to 3" as
noted by modest HREF neighborhood probabilities for >3" with a
decline to 0% for >5". The previous MRGL risk was maintained.

Hurley


Day 2
Valid 12Z Fri Jun 27 2025 - 12Z Sat Jun 28 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL OVER PORTIONS OF
NORTHERN NEW YORK AND NORTHERN NEW ENGLAND...

...Northern NY-New England...

The forecast for a focused corridor of heavy rainfall associated
with an MCS and trailing convection crossing from southeastern
Canada into portions of Update New York/northern New England
remains on track. While there are expectedly some variances on the
possible MCS path which add some east-west uncertainty, all
guidance is still in good agreement that the track will clip areas
south of the international border bringing an attendant flash flood
threat. Deterministic guidance indicates the potential of rainfall
totals between 1-3", with ensemble probabilities of 2"+ between
15-25%. A small eastward adjustment of the Slight Risk area was
added based on these latest ensemble probabilities. Elsewhere,
prior forecast has remained consistent.

...Northern Plains...

A quick moving shortwave across the North-Central tier of the CONUS
will lead to scattered thunderstorm activity capable of locally
heavy rainfall and flash flood prospects. The best threat will be
over Northern ND into the Red River area where some urbanized zones
will have a greater threat for flash flooding. A quick 1-3+" is
likely anywhere over Central ND into Northwest MN. This threat is
within the lower end of the MRGL risk threshold and will be
monitored closely to see if the risk is warranted, or needs any
expansion.

...West Texas into New Mexico...

Continued threat of widely scattered thunderstorms across far West
TX into NM will allow for isolated flash flood concerns over areas
that will have seen several days of heavy convective impacts with
compromised FFG's. Local 1-2" is possible in the period with the
highest threat likely over the Sacramento's down through the
Guadalupe Mtns. and adjacent valleys. A MRGL risk was maintained to
cover for the threat.


Day 3
Valid 12Z Sat Jun 28 2025 - 12Z Sun Jun 29 2025

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS
OF THE NORTHERN PLAINS AND UPPER MIDWEST, THE NORTHEAST, AND
SOUTH-CENTRAL NEW MEXICO...

...Northern Plains and Upper Midwest...

Next approaching upper shortwave trough, with a 90kt upper level
jet streak on the lee side, will generate a compact area of fairly
robust, transient deep-layer forcing over the outlook area later in
the period (especially Sat night). MUCAPEs are expected to soar
within the warm sector prior to the surface cold frontal passage --
i.e. aoa 4,000 J/Kg per the GFS. This along with PWs getting near
1.75" will lead to more organized, widespread convection by
Saturday night as the activity likely grows upscale with the
increasing pre-frontal low-level inflow (30-40kts at 850 mb). The
00Z guidance indicates significant latitudinal spread in the
heavier QPF, and as a result, have maintained the Marginal Risk
from yesterday's Day 4 ERO. However, the potential for an upgrade
to Slight is certainly plausible given the kinematic and
thermodynamic profile, especially after 00Z Sun when the Corfidi
Vectors decrease to 10kt or less (thereby enhancing the risk for
cell training).

...Northeast...

Upper shortwave trough pushes across the Northeast by late Sat,
then off the coast Sun morning. The bulk of the rainfall will fall
during the first half of the period (during the day Sat),
coinciding with the most favorable pre-frontal deep-layer
instability and moisture (PWs 1.75-2.00+ inches). The 00Z guidance
shows considerable spread with the heaviest QPF, though are fairly
similar with the max totals (1.5-3.0"). Given the spread in the
model QPFs, along with the progression of the front and fairly
quick diminishment in instability after 00Z Sun, for now will
maintain the Marginal Risk.

...New Mexico...

Maintained a targeted Marginal Risk area over/near the Sacramento
Mtns, particularly the burn scar areas from the 2024 fires (Blue 2,
South Fork, and Salt burn scars). QPF trends (coverage, intensity)
are similar to Day 2, with the moist S-SE low-level upslope flow
likely resulting in a concentrated area of heavier rainfall across
the Sacramento Mtns and eastern foothills. The flash flood
potential is expected to remain isolated/localized.

Hurley


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!9wAJinZoHLLfvW4cM8Xh9SDTkMYDvSOA6xu8Ej6_iTU5= lABOeXO3ng6ikcvPEuzFSsor-RwF9cKAcv6zPAbx13NwOiU$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!9wAJinZoHLLfvW4cM8Xh9SDTkMYDvSOA6xu8Ej6_iTU5= lABOeXO3ng6ikcvPEuzFSsor-RwF9cKAcv6zPAbxb6Nffcw$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!9wAJinZoHLLfvW4cM8Xh9SDTkMYDvSOA6xu8Ej6_iTU5= lABOeXO3ng6ikcvPEuzFSsor-RwF9cKAcv6zPAbxp_3dvY0$=20

=3D =3D =3D
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FOUS30 KWBC 261556
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
1156 AM EDT Thu Jun 26 2025

Day 1
Valid 16Z Thu Jun 26 2025 - 12Z Fri Jun 27 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PARTS OF
THE CENTRAL PLAINS, UPPER MIDWEST, AND UPPER GREAT LAKES, ALONG
WITH NORTHERN PORTIONS OF THE MID ATLANTIC...

...Central Plains into the Upper Great Lakes...

16Z update... The western bounds of the Marginal Risk area was
expanded westward to now include more of eastern Nebraska. Cells
are observed firing up near the heavy rain axis from yesterday and
are expected to persist for a few more hours. The latest CAM
guidance show a fairly progressive line tracking through the region
with rain rates of 1 to 3 inches/hour with maximum 24-hour=20
accumulations of 3 to 5 inches. Elsewhere the Marginal and Slight
Risk areas were maintained with no adjustments.

Campbell

Upper shortwave trough across the Northern Plains early Thu will
pivot eastward across the Upper MS Valley and Upper Great Lakes
region later Thu and Thu night. Enhancing the deep-layer forcing
will be the curved 90kt upper level jet streak that will be
skirting the U.S.-Canadian border. Ahead of the upper shortwave
trough/surface front -- 850-700 mb moisture flux anomalies are
noteworthy (1.5-2.0 standard deviations above normal), as is the
0-6km bulk shear values (35-45+ kts). This will likely support more
widespread, organized convective line segments later this
afternoon/evening and into the overnight across the elongated
Slight Risk area. Compared to yesterday's Day 2 ERO, based on the
latest guidance trends we did nudge the Slight slightly farther
east across northwest MO and southeast IA. The 00Z CAMs show 24hr
max QPF generally in the 3-5" range within the Slight Risk area,
which is supported by the HREF and RRFS 24hr QPF probabilities.
Multiple CAMs (including the 00Z RRFS) show isolated totals
exceeding 5" across eastern KS.

...Mid Atlantic...

Most of the CAMs show more widespread slow-moving convective
clusters within a newly-hoisted Slight area, initiating along the
lee-side trough and quasi-stationary, backdoor front. Relatively light (generally 20kt or less) deep-layer shear would suggest pulse-
type durations for the heaviest rains, but nevertheless both the
HREF and RRFS do show pockets of elevated probabilities with >2"/hr
rainfall rates by mid-late afternoon into Thu evening. Therefore
given the favorable thermodynamic profile (1.75-2.00" PWs and max
CAPEs 2000-3000 J/Kg), the likelihood of slow cell motions with the
potential for repetitive convection along these boundaries would
support a low-end Slight Risk across the northern Mid Atlantic
(northern VA into eastern MD and Eastern PA), despite the lack of
strong synoptic/ kinematic support.

...Parts of the Lower MS Valley, TN Valley, and Southeast...

Scattered to widely scattered thunderstorms over much of the
south-central to southeastern CONUS will yield some heavy rainfall
prospects during the day Thursday with a decay in coverage once we
lose diurnal heating. The main areas of interest will lie along
the terrain in the Southern Appalachians and along the Gulf coast
where the remnants of a migrating TUTT cell will maintain a focal
point for heavy convective prospects during the period. Best threat
for any flash flooding will be tied to the complex topography and
urban settings where runoff capabilities are highest. Relatively
modest HREF probs for >3" (40-60%) were noted across portions of
MS/LA and especially along the west coast of the FL Peninsula. For
now the risk appears to be a 'high end' Marginal, i.e. mainly an
isolated flash flood risk, largely due to the pulse/short-fused
nature of the more intense rainfall rates and relatively high FFG
values.

...New Mexico...

Isolated to scattered thunderstorms across the Sacramento's and
adjacent desert will maintain at least some threat for flash
flooding given wet antecedent conditions following previous multi-
day convective impact in prior periods. Coverage and intensity of
convection will be less than previous days as we lose the benefit
of the RER jet dynamics that have assisted in the recent days.
Still, remnant elevated moisture and sufficient buoyancy within
the confines of far West TX up through Southern and Eastern NM will
maintain a posture of diurnally driven thunderstorms with locally
heavy rainfall across the above areas. Heaviest thunderstorms will
be capable of 1-2" with the peak QPF max probably closer to 3" as
noted by modest HREF neighborhood probabilities for >3" with a
decline to 0% for >5". The previous MRGL risk was maintained.

Hurley


Day 2
Valid 12Z Fri Jun 27 2025 - 12Z Sat Jun 28 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL OVER PORTIONS OF
NORTHERN NEW YORK AND NORTHERN NEW ENGLAND...

...Northern NY-New England...

The forecast for a focused corridor of heavy rainfall associated
with an MCS and trailing convection crossing from southeastern
Canada into portions of Update New York/northern New England
remains on track. While there are expectedly some variances on the
possible MCS path which add some east-west uncertainty, all
guidance is still in good agreement that the track will clip areas
south of the international border bringing an attendant flash flood
threat. Deterministic guidance indicates the potential of rainfall
totals between 1-3", with ensemble probabilities of 2"+ between
15-25%. A small eastward adjustment of the Slight Risk area was
added based on these latest ensemble probabilities. Elsewhere,
prior forecast has remained consistent.

...Northern Plains...

A quick moving shortwave across the North-Central tier of the CONUS
will lead to scattered thunderstorm activity capable of locally
heavy rainfall and flash flood prospects. The best threat will be
over Northern ND into the Red River area where some urbanized zones
will have a greater threat for flash flooding. A quick 1-3+" is
likely anywhere over Central ND into Northwest MN. This threat is
within the lower end of the MRGL risk threshold and will be
monitored closely to see if the risk is warranted, or needs any
expansion.

...West Texas into New Mexico...

Continued threat of widely scattered thunderstorms across far West
TX into NM will allow for isolated flash flood concerns over areas
that will have seen several days of heavy convective impacts with
compromised FFG's. Local 1-2" is possible in the period with the
highest threat likely over the Sacramento's down through the
Guadalupe Mtns. and adjacent valleys. A MRGL risk was maintained to
cover for the threat.


Day 3
Valid 12Z Sat Jun 28 2025 - 12Z Sun Jun 29 2025

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS
OF THE NORTHERN PLAINS AND UPPER MIDWEST, THE NORTHEAST, AND
SOUTH-CENTRAL NEW MEXICO...

...Northern Plains and Upper Midwest...

Next approaching upper shortwave trough, with a 90kt upper level
jet streak on the lee side, will generate a compact area of fairly
robust, transient deep-layer forcing over the outlook area later in
the period (especially Sat night). MUCAPEs are expected to soar
within the warm sector prior to the surface cold frontal passage --
i.e. aoa 4,000 J/Kg per the GFS. This along with PWs getting near
1.75" will lead to more organized, widespread convection by
Saturday night as the activity likely grows upscale with the
increasing pre-frontal low-level inflow (30-40kts at 850 mb). The
00Z guidance indicates significant latitudinal spread in the
heavier QPF, and as a result, have maintained the Marginal Risk
from yesterday's Day 4 ERO. However, the potential for an upgrade
to Slight is certainly plausible given the kinematic and
thermodynamic profile, especially after 00Z Sun when the Corfidi
Vectors decrease to 10kt or less (thereby enhancing the risk for
cell training).

...Northeast...

Upper shortwave trough pushes across the Northeast by late Sat,
then off the coast Sun morning. The bulk of the rainfall will fall
during the first half of the period (during the day Sat),
coinciding with the most favorable pre-frontal deep-layer
instability and moisture (PWs 1.75-2.00+ inches). The 00Z guidance
shows considerable spread with the heaviest QPF, though are fairly
similar with the max totals (1.5-3.0"). Given the spread in the
model QPFs, along with the progression of the front and fairly
quick diminishment in instability after 00Z Sun, for now will
maintain the Marginal Risk.

...New Mexico...

Maintained a targeted Marginal Risk area over/near the Sacramento
Mtns, particularly the burn scar areas from the 2024 fires (Blue 2,
South Fork, and Salt burn scars). QPF trends (coverage, intensity)
are similar to Day 2, with the moist S-SE low-level upslope flow
likely resulting in a concentrated area of heavier rainfall across
the Sacramento Mtns and eastern foothills. The flash flood
potential is expected to remain isolated/localized.

Hurley


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!64UhPvAL77LE53bBvE4XWdAP3TECAOTdafRXkMzfMPTQ= bJQKamHsE9hhpnWDXu6w2xmrSG4s7w3SZq0PVK3iqDDrc20$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!64UhPvAL77LE53bBvE4XWdAP3TECAOTdafRXkMzfMPTQ= bJQKamHsE9hhpnWDXu6w2xmrSG4s7w3SZq0PVK3iOPhjkgM$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!64UhPvAL77LE53bBvE4XWdAP3TECAOTdafRXkMzfMPTQ= bJQKamHsE9hhpnWDXu6w2xmrSG4s7w3SZq0PVK3ioVmZw1M$=20

=3D =3D =3D
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FOUS30 KWBC 262018
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
418 PM EDT Thu Jun 26 2025

Day 1
Valid 16Z Thu Jun 26 2025 - 12Z Fri Jun 27 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PARTS OF
THE CENTRAL PLAINS, UPPER MIDWEST, AND UPPER GREAT LAKES, ALONG
WITH NORTHERN PORTIONS OF THE MID ATLANTIC...

...Central Plains into the Upper Great Lakes...

16Z update... The western bounds of the Marginal Risk area was
expanded westward to now include more of eastern Nebraska. Cells
are observed firing up near the heavy rain axis from yesterday and
are expected to persist for a few more hours. The latest CAM
guidance show a fairly progressive line tracking through the region
with rain rates of 1 to 3 inches/hour with maximum 24-hour
accumulations of 3 to 5 inches. Elsewhere the Marginal and Slight
Risk areas were maintained with no adjustments.

Campbell

Upper shortwave trough across the Northern Plains early Thu will
pivot eastward across the Upper MS Valley and Upper Great Lakes
region later Thu and Thu night. Enhancing the deep-layer forcing
will be the curved 90kt upper level jet streak that will be
skirting the U.S.-Canadian border. Ahead of the upper shortwave
trough/surface front -- 850-700 mb moisture flux anomalies are
noteworthy (1.5-2.0 standard deviations above normal), as is the
0-6km bulk shear values (35-45+ kts). This will likely support more
widespread, organized convective line segments later this
afternoon/evening and into the overnight across the elongated
Slight Risk area. Compared to yesterday's Day 2 ERO, based on the
latest guidance trends we did nudge the Slight slightly farther
east across northwest MO and southeast IA. The 00Z CAMs show 24hr
max QPF generally in the 3-5" range within the Slight Risk area,
which is supported by the HREF and RRFS 24hr QPF probabilities.
Multiple CAMs (including the 00Z RRFS) show isolated totals
exceeding 5" across eastern KS.

...Mid Atlantic...

Most of the CAMs show more widespread slow-moving convective
clusters within a newly-hoisted Slight area, initiating along the
lee-side trough and quasi-stationary, backdoor front. Relatively light (generally 20kt or less) deep-layer shear would suggest pulse-
type durations for the heaviest rains, but nevertheless both the
HREF and RRFS do show pockets of elevated probabilities with >2"/hr
rainfall rates by mid-late afternoon into Thu evening. Therefore
given the favorable thermodynamic profile (1.75-2.00" PWs and max
CAPEs 2000-3000 J/Kg), the likelihood of slow cell motions with the
potential for repetitive convection along these boundaries would
support a low-end Slight Risk across the northern Mid Atlantic
(northern VA into eastern MD and Eastern PA), despite the lack of
strong synoptic/ kinematic support.

...Parts of the Lower MS Valley, TN Valley, and Southeast...

Scattered to widely scattered thunderstorms over much of the
south-central to southeastern CONUS will yield some heavy rainfall
prospects during the day Thursday with a decay in coverage once we
lose diurnal heating. The main areas of interest will lie along
the terrain in the Southern Appalachians and along the Gulf coast
where the remnants of a migrating TUTT cell will maintain a focal
point for heavy convective prospects during the period. Best threat
for any flash flooding will be tied to the complex topography and
urban settings where runoff capabilities are highest. Relatively
modest HREF probs for >3" (40-60%) were noted across portions of
MS/LA and especially along the west coast of the FL Peninsula. For
now the risk appears to be a 'high end' Marginal, i.e. mainly an
isolated flash flood risk, largely due to the pulse/short-fused
nature of the more intense rainfall rates and relatively high FFG
values.

...New Mexico...

Isolated to scattered thunderstorms across the Sacramento's and
adjacent desert will maintain at least some threat for flash
flooding given wet antecedent conditions following previous multi-
day convective impact in prior periods. Coverage and intensity of
convection will be less than previous days as we lose the benefit
of the RER jet dynamics that have assisted in the recent days.
Still, remnant elevated moisture and sufficient buoyancy within
the confines of far West TX up through Southern and Eastern NM will
maintain a posture of diurnally driven thunderstorms with locally
heavy rainfall across the above areas. Heaviest thunderstorms will
be capable of 1-2" with the peak QPF max probably closer to 3" as
noted by modest HREF neighborhood probabilities for >3" with a
decline to 0% for >5". The previous MRGL risk was maintained.

Hurley


Day 2
Valid 12Z Fri Jun 27 2025 - 12Z Sat Jun 28 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL OVER PORTIONS OF
NORTHERN NEW YORK AND NORTHERN NEW ENGLAND...

...Northern NY-New England...

21Z update... the latest guidance maintains the scenario described
below with similiar QPF amounts, particularly from northeast New
York to northern Vermont, therefore the Marginal and Slight Risk
areas were maintained as is.

Campbell

The forecast for a focused corridor of heavy rainfall associated
with an MCS and trailing convection crossing from southeastern
Canada into portions of Update New York/northern New England
remains on track. While there are expectedly some variances on the
possible MCS path which add some east-west uncertainty, all
guidance is still in good agreement that the track will clip areas
south of the international border bringing an attendant flash flood
threat. Deterministic guidance indicates the potential of rainfall
totals between 1-3", with ensemble probabilities of 2"+ between
15-25%. A small eastward adjustment of the Slight Risk area was
added based on these latest ensemble probabilities. Elsewhere,
prior forecast has remained consistent.

...Northern Plains...

21Z update... The progressive nature of the expected shortwave will
help limit the severity of any local flooding that arises. The
Marginal Risk currently in place remains without any changes at
this time.

Campbell

A quick moving shortwave across the North-Central tier of the CONUS
will lead to scattered thunderstorm activity capable of locally
heavy rainfall and flash flood prospects. The best threat will be
over Northern ND into the Red River area where some urbanized zones
will have a greater threat for flash flooding. A quick 1-3+" is
likely anywhere over Central ND into Northwest MN. This threat is
within the lower end of the MRGL risk threshold and will be
monitored closely to see if the risk is warranted, or needs any
expansion.

...West Texas into New Mexico...

21Z update... The threat for localized heavy rainfall remains
spotty across the area given the pattern. The Marginal Risk area
continues to highlight the locations that may have local flash
flooding during this period.

Campbell

Continued threat of widely scattered thunderstorms across far West
TX into NM will allow for isolated flash flood concerns over areas
that will have seen several days of heavy convective impacts with
compromised FFG's. Local 1-2" is possible in the period with the
highest threat likely over the Sacramento's down through the
Guadalupe Mtns. and adjacent valleys. A MRGL risk was maintained to
cover for the threat.


Day 3
Valid 12Z Sat Jun 28 2025 - 12Z Sun Jun 29 2025

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS
OF THE NORTHERN PLAINS AND UPPER MIDWEST, THE NORTHEAST, AND
SOUTH-CENTRAL NEW MEXICO...

...Northern Plains and Upper Midwest...

21Z update... The latest guidance continues to signal the highest
QPF amounts to be over central Minnesota into western/northern
Wisconsin with areal averages of 1 to 3 inches with locally higher
amounts still possible. The environment looks to remain favorable
for repeating cells, thus maintaining an elevated threat for
localized flash flooding.

Campbell

Next approaching upper shortwave trough, with a 90kt upper level
jet streak on the lee side, will generate a compact area of fairly
robust, transient deep-layer forcing over the outlook area later in
the period (especially Sat night). MUCAPEs are expected to soar
within the warm sector prior to the surface cold frontal passage --
i.e. aoa 4,000 J/Kg per the GFS. This along with PWs getting near
1.75" will lead to more organized, widespread convection by
Saturday night as the activity likely grows upscale with the
increasing pre-frontal low-level inflow (30-40kts at 850 mb). The
00Z guidance indicates significant latitudinal spread in the
heavier QPF, and as a result, have maintained the Marginal Risk
from yesterday's Day 4 ERO. However, the potential for an upgrade
to Slight is certainly plausible given the kinematic and
thermodynamic profile, especially after 00Z Sun when the Corfidi
Vectors decrease to 10kt or less (thereby enhancing the risk for
cell training).

...Northeast...

21Z update... There is an increasing potential for heavy rainfall
to develop across western Pennslyvania and surrounding areas as=20
the frontal boundary sags southward and taps into the pooled PW=20
values of 1.5-2". The latest model guidance are showing local=20
maximums upwards of 2 inches possible and the ERO first guess=20
supports expanding the Marginal Risk from eastern Pennsylvania=20
further west into eastern Ohio, West Virginia and western Maryland.

Campbell

Upper shortwave trough pushes across the Northeast by late Sat,=20
then off the coast Sun morning. The bulk of the rainfall will fall=20
during the first half of the period (during the day Sat),=20
coinciding with the most favorable pre-frontal deep-layer=20
instability and moisture (PWs 1.75-2.00+ inches). The 00Z guidance=20
shows considerable spread with the heaviest QPF, though are fairly=20
similar with the max totals (1.5-3.0"). Given the spread in the=20
model QPFs, along with the progression of the front and fairly=20
quick diminishment in instability after 00Z Sun, for now will=20
maintain the Marginal Risk.

...New Mexico...

21Z update... No changes were made to the Marginal Risk area.

Campbell

Maintained a targeted Marginal Risk area over/near the Sacramento=20
Mtns, particularly the burn scar areas from the 2024 fires (Blue 2,
South Fork, and Salt burn scars). QPF trends (coverage, intensity)
are similar to Day 2, with the moist S-SE low-level upslope flow=20
likely resulting in a concentrated area of heavier rainfall across=20
the Sacramento Mtns and eastern foothills. The flash flood=20
potential is expected to remain isolated/localized.

Hurley


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!5hGnIOwi7dNZjqNz9aUpDb7GKb7GWFF0kcjJOvTuEgRd= H8kJ7nAf5JH0Ztro_p4j1iM6pKhArkwMqUa1lecS9Km6Ni8$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!5hGnIOwi7dNZjqNz9aUpDb7GKb7GWFF0kcjJOvTuEgRd= H8kJ7nAf5JH0Ztro_p4j1iM6pKhArkwMqUa1lecStSdxjTY$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!5hGnIOwi7dNZjqNz9aUpDb7GKb7GWFF0kcjJOvTuEgRd= H8kJ7nAf5JH0Ztro_p4j1iM6pKhArkwMqUa1lecSNOtrnaY$=20

=3D =3D =3D
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FOUS30 KWBC 270049
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
849 PM EDT Thu Jun 26 2025

Day 1
Valid 01Z Fri Jun 27 2025 - 12Z Fri Jun 27 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PARTS OF
THE CENTRAL PLAINS, MIDWEST, & GREAT LAKES...

An upper level trough will pivot eastward across the Upper MS=20
Valley and Upper Great Lakes region Thursday night into early
Friday. Enhancing the deep-layer forcing will be the curved 90kt=20
upper level jet streak that will be skirting the U.S.-Canadian=20
border. Ahead of the upper shortwave trough/surface front --=20
850-700 mb moisture flux anomalies are noteworthy (1.5-2.0 standard
deviations above normal), as is the 0-6km bulk shear values=20
(35-45+ kts). This will likely continue to support more widespread,
organized convective line segments into the overnight across the=20
elongated Slight Risk area, with embedded mesocyclones possible.=20
When compared to continuity, cleared the former western portions of
the risk areas based on radar reflectivity trends and 18z HREF=20
output.


...Mid Atlantic & Upper Ohio Valley...=20
Relatively light (generally 20kt or less) deep-layer shear with=20
a near upper level high overhead between a retrograding TUTT cell
in the Southeast and Westerlies to the north has caused a Florida-
like situation to unfold today, with outflow boundaries moving in
from many directions of the compass, which has caused CIN to set in
across much of the region. The most interesting aspect has been a
synoptically enhanced sea breeze, a possible cold front that=20
cleared portions of the Eastern Shore this afternoon and evening=20
and has led to patches of stratus in its wake over portions of NJ=20
& DE. The 18z HREF has significantly overforecast early evening=20
convection in the DC area in the hours leading up to this=20
discussion's issuance. With convective coverage becoming more=20
isolated due to the broad CIN development, dropped the risk in the=20
region to Marginal. The 18z HREF indicates that the threat of heavy
rainfall on an isolated basis should end by midnight, holding on=20
the longest across portions southern PA, the Virginias, and near=20
the shores of Chesapeake Bay.


...New Mexico...
Isolated to scattered thunderstorms across the Southern High Plains
and the Texas Big Bend should maintain at least some threat for=20
flash flooding given wet antecedent conditions following a wet=20
multi-day convective period. Remaining elevated moisture and=20
sufficient buoyancy will maintain the diurnally driven=20
thunderstorms through roughly 05z, based on the 18z HREF output.=20
Heaviest thunderstorms will be capable of 1-2" with the peak QPF=20
max probably closer to 3". The previous MRGL risk was maintained,
but trimmed on its western side per radar trends and the 18z HREF
output.

Roth/Hurley


Day 2
Valid 12Z Fri Jun 27 2025 - 12Z Sat Jun 28 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL OVER PORTIONS OF
NORTHERN NEW YORK AND NORTHERN NEW ENGLAND...

...Northern NY-New England...

21Z update... the latest guidance maintains the scenario described
below with similar QPF amounts, particularly from northeast New=20
York to northern Vermont, therefore the Marginal and Slight Risk=20
areas were maintained as is.

Campbell

The forecast for a focused corridor of heavy rainfall associated
with an MCS and trailing convection crossing from southeastern
Canada into portions of Update New York/northern New England
remains on track. While there are expectedly some variances on the
possible MCS path which add some east-west uncertainty, all
guidance is still in good agreement that the track will clip areas
south of the international border bringing an attendant flash flood
threat. Deterministic guidance indicates the potential of rainfall
totals between 1-3", with ensemble probabilities of 2"+ between
15-25%. A small eastward adjustment of the Slight Risk area was
added based on these latest ensemble probabilities. Elsewhere,
prior forecast has remained consistent.

...Northern Plains...

21Z update... The progressive nature of the expected shortwave will
help limit the severity of any local flooding that arises. The
Marginal Risk currently in place remains without any changes at
this time.

Campbell

A quick moving shortwave across the North-Central tier of the CONUS
will lead to scattered thunderstorm activity capable of locally
heavy rainfall and flash flood prospects. The best threat will be
over Northern ND into the Red River area where some urbanized zones
will have a greater threat for flash flooding. A quick 1-3+" is
likely anywhere over Central ND into Northwest MN. This threat is
within the lower end of the MRGL risk threshold and will be
monitored closely to see if the risk is warranted, or needs any
expansion.

...West Texas into New Mexico...

21Z update... The threat for localized heavy rainfall remains
spotty across the area given the pattern. The Marginal Risk area
continues to highlight the locations that may have local flash
flooding during this period.

Campbell

Continued threat of widely scattered thunderstorms across far West
TX into NM will allow for isolated flash flood concerns over areas
that will have seen several days of heavy convective impacts with
compromised FFG's. Local 1-2" is possible in the period with the
highest threat likely over the Sacramento's down through the
Guadalupe Mtns. and adjacent valleys. A MRGL risk was maintained to
cover for the threat.


Day 3
Valid 12Z Sat Jun 28 2025 - 12Z Sun Jun 29 2025

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS
OF THE NORTHERN PLAINS AND UPPER MIDWEST, THE NORTHEAST, AND
SOUTH-CENTRAL NEW MEXICO...

...Northern Plains and Upper Midwest...

21Z update... The latest guidance continues to signal the highest
QPF amounts to be over central Minnesota into western/northern
Wisconsin with areal averages of 1 to 3 inches with locally higher
amounts still possible. The environment looks to remain favorable
for repeating cells, thus maintaining an elevated threat for
localized flash flooding.

Campbell

Next approaching upper shortwave trough, with a 90kt upper level
jet streak on the lee side, will generate a compact area of fairly
robust, transient deep-layer forcing over the outlook area later in
the period (especially Sat night). MUCAPEs are expected to soar
within the warm sector prior to the surface cold frontal passage --
i.e. aoa 4,000 J/Kg per the GFS. This along with PWs getting near
1.75" will lead to more organized, widespread convection by
Saturday night as the activity likely grows upscale with the
increasing pre-frontal low-level inflow (30-40kts at 850 mb). The
00Z guidance indicates significant latitudinal spread in the
heavier QPF, and as a result, have maintained the Marginal Risk
from yesterday's Day 4 ERO. However, the potential for an upgrade
to Slight is certainly plausible given the kinematic and
thermodynamic profile, especially after 00Z Sun when the Corfidi
Vectors decrease to 10kt or less (thereby enhancing the risk for
cell training).

...Northeast...

21Z update... There is an increasing potential for heavy rainfall
to develop across western Pennsylvania and surrounding areas as
the frontal boundary sags southward and taps into the pooled PW
values of 1.5-2". The latest model guidance are showing local
maximums upwards of 2 inches possible and the ERO first guess
supports expanding the Marginal Risk from eastern Pennsylvania
further west into eastern Ohio, West Virginia and western Maryland.

Campbell

Upper shortwave trough pushes across the Northeast by late Sat,
then off the coast Sun morning. The bulk of the rainfall will fall
during the first half of the period (during the day Sat),
coinciding with the most favorable pre-frontal deep-layer
instability and moisture (PWs 1.75-2.00+ inches). The 00Z guidance
shows considerable spread with the heaviest QPF, though are fairly
similar with the max totals (1.5-3.0"). Given the spread in the
model QPFs, along with the progression of the front and fairly
quick diminishment in instability after 00Z Sun, for now will
maintain the Marginal Risk.

...New Mexico...

21Z update... No changes were made to the Marginal Risk area.

Campbell

Maintained a targeted Marginal Risk area over/near the Sacramento
Mtns, particularly the burn scar areas from the 2024 fires (Blue 2,
South Fork, and Salt burn scars). QPF trends (coverage, intensity)
are similar to Day 2, with the moist S-SE low-level upslope flow
likely resulting in a concentrated area of heavier rainfall across
the Sacramento Mtns and eastern foothills. The flash flood
potential is expected to remain isolated/localized.

Hurley


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!6BKAZzJ368AWHYuruuCGKuI3ZdH4XPh2dqqvVvy_7tqG= F7irjNEG5P0TZVuXbH0CK8Cy9om0Eaj2kpmi4rD5otEkBWU$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!6BKAZzJ368AWHYuruuCGKuI3ZdH4XPh2dqqvVvy_7tqG= F7irjNEG5P0TZVuXbH0CK8Cy9om0Eaj2kpmi4rD5ecBhPcA$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!6BKAZzJ368AWHYuruuCGKuI3ZdH4XPh2dqqvVvy_7tqG= F7irjNEG5P0TZVuXbH0CK8Cy9om0Eaj2kpmi4rD51MsDtwo$=20

=3D =3D =3D
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FOUS30 KWBC 270829
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
429 AM EDT Fri Jun 27 2025

Day 1
Valid 12Z Fri Jun 27 2025 - 12Z Sat Jun 28 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL OVER PORTIONS OF
THE CENTRAL APPALACHIANS AND NEIGHBORING MID ATLANTIC...

...Northern NY-New England...

The suite of 00Z operational models and ensemble runs continued a=20
trend started during the day on Thursday of shifting the focus for=20
heavy rainfall to remain north of the international border. Even=20
though there are some variances on the possible MCS path which=20
could still result in an MCS clipping the northern portion of New
York and New England...it should fall in a region where Flash Flood
Guidance is higher than adjacent areas so the Slight Risk was
removed and the Marginal Risk area was removed from the upper
Hudson Valley and southward.=20

At the same time...introduced a Slight risk area over portions of
the central Appalachians where model signals have been growing for
enhanced rainfall amounts near the terrain. With a westward
propagating cold front encountering the terrain... the higher
amounts suggested by the latest HRRR runs seems reasonable and was
placed near the axis of heaviest rainfall from the WPC
deterministic QPF.


...Northern Plains...

A quick moving shortwave across the northern and central tier of=20
the CONUS will lead to scattered thunderstorm activity capable of=20
locally heavy rainfall. Prospects for flash flooding seem to be=20
limited given the progressive nature of the shortwave trough which=20
should help focus the convection. A quick 1-3+" is likely anywhere=20
over parts of the eastern Dakotas and across central Minnesota.=20
This threat remained within the lower end of the MRGL risk=20
threshold and will be monitored closely.

...West Texas into New Mexico...

Continued threat of widely scattered thunderstorms across far West
Texas into New Mexico again over an area that will have seen=20
several days of heavy convective impacts with compromised Flash=20
Flood Guidance. Local 1- to 2-inch amounts are possible in the=20
period with the highest threat likely over the Sacramento's down=20
through the Guadalupe Mountains and adjacent valleys. A Marginal=20
risk was maintained to cover for the threat.

Bann

Day 2
Valid 12Z Sat Jun 28 2025 - 12Z Sun Jun 29 2025

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS=20
OF THE NORTHERN PLAINS AND UPPER MIDWEST, THE NORTHEAST, AND SOUTH-
CENTRAL NEW MEXICO...

...Northern Plains and Upper Midwest...

Next approaching upper shortwave trough, with a 90kt upper level=20
jet streak on the lee side, will generate a compact area of fairly=20
robust, transient deep-layer forcing over the outlook area mainly=20
Saturday night. later in the period (especially Sat night). MUCAPEs
are expected to soar within the warm sector prior to the surface=20
cold frontal passage. Given precipitable water values getting near=20
1.75 inches...storms which form the unstable airmass will be=20
capable of producing rainfall rates in excess of 1 inch per hour=20
and areal average rainfall amounts of 1 to 3 inches...especially=20
once low- level inflow accelerates to between 30 kts and 40kts at=20
850 mb ahead of the approaching front.

...Northeast...

There continues to be an increasing concern for heavy to
potentially excessive rainfall to develop across western=20
Pennsylvania and surrounding areas as the frontal boundary sags=20
southward and taps into the pooled PW values of 1.5-2". The latest=20
model guidance are showing local maximums upwards of 2 inches=20
possible and the ERO first guess supports expanding the Marginal=20
Risk from eastern Pennsylvania further west into eastern Ohio, West
Virginia and western Maryland.

...New Mexico...

Maintained a targeted Marginal Risk area over/near the Sacramento=20
Mtns, particularly in vicinity of burn scars. QPF trends=20
(coverage, intensity) are similar to Day 1, with the moist south to
southeast low-level upslope flow likely resulting in a=20
concentrated area of heavier rainfall across the Sacramento Mtns=20
and eastern foothills. The flash flood potential is expected to=20
remain isolated/localized.

Bann

Day 3
Valid 12Z Sun Jun 29 2025 - 12Z Mon Jun 30 2025

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL EXTENDING OVER
PORTIONS OF THE CENTRAL UNITED STATES...

There is a Marginal Risk of excessive rainfall over portions of the
central United States between the western Great Lakes and the
Southern Rockies. Any showers or thunderstorms which form along or
ahead of the front may be able to produce rainfall rates high
enough to result in flash flooding. Away from the upper
trough...mechanisms to help focus convection becomes less defined=20
in an atmosphere characterized by precipitable water values in=20
excess of 1.5 inches over all but the plains near the Central and=20
Southern Rockies to in excess of 2 inches east of the Mississippi.=20
Ensemble guidance depicted isolated to widely scattered rainfall=20
amounts of 1 to 3 inches but little coherence in placement between=20
the ensemble runs. Opted to highlight a broad but generally=20
unfocused Marginal risk area .

Bann


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!_vTWP9wGSqflxANjq2y8UWn4nqKFWf_xV5H2VS-3kvVp= 0OzNBFirJTXkOvkktIrCRmHp9KH8pBEL6o3HBJIokS3Z1ig$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!_vTWP9wGSqflxANjq2y8UWn4nqKFWf_xV5H2VS-3kvVp= 0OzNBFirJTXkOvkktIrCRmHp9KH8pBEL6o3HBJIoHny4Az0$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!_vTWP9wGSqflxANjq2y8UWn4nqKFWf_xV5H2VS-3kvVp= 0OzNBFirJTXkOvkktIrCRmHp9KH8pBEL6o3HBJIo97KWvAA$=20

=3D =3D =3D
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FOUS30 KWBC 271555
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
1155 AM EDT Fri Jun 27 2025

Day 1
Valid 16Z Fri Jun 27 2025 - 12Z Sat Jun 28 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL OVER PORTIONS OF
THE CENTRAL APPALACHIANS...

...Central Appalachians...

A more focused thunderstorm/heavy rainfall threat is expected=20
through the central Appalachians today as very moist flow interacts
with the terrain ahead of a 'back-door' cold front passing through
the Mid-Atlantic that will become quasi-stationary throughout the=20
day. Of particular concern is the prospect suggested by some of the
12Z hi-res guidance (HRRR and HREF) that initial storms over parts
of western Maryland/West Virgina Panhandle/northwestern Virginia=20
will cluster/organize and move slowly southward along the=20
instability gradient ahead of the stalling front. Updated 12Z HREF=20 probabilities are between 40-60% for rainfall of 3"+, with a=20
focused area of 20-30% of 5"+ across the West Virginia Panhandle.=20
Efficient rainfall rates of 1-2.5" per hour can be expected given=20
PWATs upwards of 2" per 12Z PBZ sounding. Much of this region=20
remains more sensitive to additional rainfall not only due to the=20
typical terrain impacts but a number of recent heavy rainfall=20
events keeping FFGs low, with scattered to potentially numerous=20
instances of flash flooding possible.=20

...Northern NY-New England...

The suite of 12Z operational models and ensemble runs continues a=20
trend started during the day on Thursday of shifting the focus for=20
heavy rainfall to remain north of the international border. Even=20
though there are some variances on the possible MCS path which=20
could still result in an MCS clipping the northern portion of New=20
York and New England...it should fall in a region where Flash Flood
Guidance is higher than adjacent areas so the Slight Risk was=20
removed and the Marginal Risk area was removed from the upper=20
Hudson Valley and southward.

...Southern Plains into the Mississippi Valley and Southeast...

Another typical Summer day of scattered thunderstorms is expected=20
broadly from the Southeast through the Mississippi Valley and west=20
along a surface trough through the southern Plains given seasonable
instability with daytime heating and a passing upper- wave. Pulse-
type thunderstorms will have the ability to produce quick efficient
bursts of heavy rainfall (1-3") and the risk for some mostly=20
isolated urban flooding, especially where any storms=20
develop/congeal along residual outflows.=20

...Northern Plains...

A quick moving shortwave across the northern and central tier of=20
the CONUS will lead to thunderstorm activity capable of locally=20
heavy rainfall, especially if convection can grow upscale into a=20
more organized MCS as indicated by some of the 12Z hi-res model=20
guidance. However, prospects for flash flooding still seem to be=20
limited given the progressive nature of the shortwave=20
trough/possible MCS. A quick 1-3+" is likely anywhere over parts of
the eastern Dakotas and across central Minnesota.

...West Texas into New Mexico...

Continued threat of widely scattered thunderstorms across far West
Texas into New Mexico again over an area that will have seen=20
several days of heavy convective impacts with compromised Flash=20
Flood Guidance. Local 1- to 2-inch amounts are possible in the=20
period with the highest threat likely over the Sacramento's down=20
through the Guadalupe Mountains and adjacent valleys. A Marginal=20
risk was maintained to cover for the threat.

Putnam/Bann

Day 2
Valid 12Z Sat Jun 28 2025 - 12Z Sun Jun 29 2025

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS
OF THE NORTHERN PLAINS AND UPPER MIDWEST, THE NORTHEAST, AND SOUTH-
CENTRAL NEW MEXICO...

...Northern Plains and Upper Midwest...

Next approaching upper shortwave trough, with a 90kt upper level
jet streak on the lee side, will generate a compact area of fairly
robust, transient deep-layer forcing over the outlook area mainly
Saturday night. later in the period (especially Sat night). MUCAPEs
are expected to soar within the warm sector prior to the surface
cold frontal passage. Given precipitable water values getting near
1.75 inches...storms which form the unstable airmass will be
capable of producing rainfall rates in excess of 1 inch per hour
and areal average rainfall amounts of 1 to 3 inches...especially
once low- level inflow accelerates to between 30 kts and 40kts at
850 mb ahead of the approaching front.

...Northeast...

There continues to be an increasing concern for heavy to
potentially excessive rainfall to develop across western
Pennsylvania and surrounding areas as the frontal boundary sags
southward and taps into the pooled PW values of 1.5-2". The latest
model guidance are showing local maximums upwards of 2 inches
possible and the ERO first guess supports expanding the Marginal
Risk from eastern Pennsylvania further west into eastern Ohio, West
Virginia and western Maryland.

...New Mexico...

Maintained a targeted Marginal Risk area over/near the Sacramento
Mtns, particularly in vicinity of burn scars. QPF trends
(coverage, intensity) are similar to Day 1, with the moist south to
southeast low-level upslope flow likely resulting in a
concentrated area of heavier rainfall across the Sacramento Mtns
and eastern foothills. The flash flood potential is expected to
remain isolated/localized.

Bann

Day 3
Valid 12Z Sun Jun 29 2025 - 12Z Mon Jun 30 2025

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL EXTENDING OVER
PORTIONS OF THE CENTRAL UNITED STATES...

There is a Marginal Risk of excessive rainfall over portions of the
central United States between the western Great Lakes and the
Southern Rockies. Any showers or thunderstorms which form along or
ahead of the front may be able to produce rainfall rates high
enough to result in flash flooding. Away from the upper
trough...mechanisms to help focus convection becomes less defined
in an atmosphere characterized by precipitable water values in
excess of 1.5 inches over all but the plains near the Central and
Southern Rockies to in excess of 2 inches east of the Mississippi.
Ensemble guidance depicted isolated to widely scattered rainfall
amounts of 1 to 3 inches but little coherence in placement between
the ensemble runs. Opted to highlight a broad but generally
unfocused Marginal risk area .

Bann


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!6_ApaL5lYdUKKXpNvyoerWIcnRAKxnQ6GzRs_7XL3h9C= lzDQpoG97RnPzFis3g5kuYLTQXRz5AfqbC0YxIBygCGuNtk$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!6_ApaL5lYdUKKXpNvyoerWIcnRAKxnQ6GzRs_7XL3h9C= lzDQpoG97RnPzFis3g5kuYLTQXRz5AfqbC0YxIByAvIpTVo$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!6_ApaL5lYdUKKXpNvyoerWIcnRAKxnQ6GzRs_7XL3h9C= lzDQpoG97RnPzFis3g5kuYLTQXRz5AfqbC0YxIBytrgzURU$=20

=3D =3D =3D
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FOUS30 KWBC 271927
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
327 PM EDT Fri Jun 27 2025

Day 1
Valid 16Z Fri Jun 27 2025 - 12Z Sat Jun 28 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL OVER PORTIONS OF
THE CENTRAL APPALACHIANS...

...Central Appalachians...

A more focused thunderstorm/heavy rainfall threat is expected
through the central Appalachians today as very moist flow interacts
with the terrain ahead of a 'back-door' cold front passing through
the Mid-Atlantic that will become quasi-stationary throughout the
day. Of particular concern is the prospect suggested by some of the
12Z hi-res guidance (HRRR and HREF) that initial storms over parts
of western Maryland/West Virgina Panhandle/northwestern Virginia
will cluster/organize and move slowly southward along the
instability gradient ahead of the stalling front. Updated 12Z HREF probabilities are between 40-60% for rainfall of 3"+, with a
focused area of 20-30% of 5"+ across the West Virginia Panhandle.
Efficient rainfall rates of 1-2.5" per hour can be expected given
PWATs upwards of 2" per 12Z PBZ sounding. Much of this region
remains more sensitive to additional rainfall not only due to the
typical terrain impacts but a number of recent heavy rainfall
events keeping FFGs low, with scattered to potentially numerous
instances of flash flooding possible.

...Northern NY-New England...

The suite of 12Z operational models and ensemble runs continues a
trend started during the day on Thursday of shifting the focus for
heavy rainfall to remain north of the international border. Even
though there are some variances on the possible MCS path which
could still result in an MCS clipping the northern portion of New
York and New England...it should fall in a region where Flash Flood
Guidance is higher than adjacent areas so the Slight Risk was
removed and the Marginal Risk area was removed from the upper
Hudson Valley and southward.

...Southern Plains into the Mississippi Valley and Southeast...

Another typical Summer day of scattered thunderstorms is expected
broadly from the Southeast through the Mississippi Valley and west
along a surface trough through the southern Plains given seasonable
instability with daytime heating and a passing upper- wave. Pulse-
type thunderstorms will have the ability to produce quick efficient
bursts of heavy rainfall (1-3") and the risk for some mostly
isolated urban flooding, especially where any storms
develop/congeal along residual outflows.

...Northern Plains...

A quick moving shortwave across the northern and central tier of
the CONUS will lead to thunderstorm activity capable of locally
heavy rainfall, especially if convection can grow upscale into a
more organized MCS as indicated by some of the 12Z hi-res model
guidance. However, prospects for flash flooding still seem to be
limited given the progressive nature of the shortwave
trough/possible MCS. A quick 1-3+" is likely anywhere over parts of
the eastern Dakotas and across central Minnesota.

...West Texas into New Mexico...

Continued threat of widely scattered thunderstorms across far West
Texas into New Mexico again over an area that will have seen
several days of heavy convective impacts with compromised Flash
Flood Guidance. Local 1- to 2-inch amounts are possible in the
period with the highest threat likely over the Sacramento's down
through the Guadalupe Mountains and adjacent valleys. A Marginal
risk was maintained to cover for the threat.

Putnam/Bann

Day 2
Valid 12Z Sat Jun 28 2025 - 12Z Sun Jun 29 2025

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS
OF THE NORTHERN PLAINS AND UPPER MIDWEST, THE NORTHEAST, AND SOUTH-
CENTRAL NEW MEXICO...

...Northern Plains and Upper Midwest...

Next approaching upper shortwave trough, with a 90kt upper level=20
jet streak on the lee side, will generate a compact area of fairly=20
robust, transient deep-layer forcing over the outlook area into=20
Saturday night. MUCAPEs are expected to soar within the warm sector
prior to the surface cold frontal passage. Given precipitable=20
water values getting near 1.75 inches...storms which form within=20
the unstable airmass will be capable of producing rainfall rates in
excess of 1 inch per hour and areal average rainfall amounts of 1=20
to 3 inches...especially once low- level inflow accelerates to=20
between 30 kts and 40kts at 850 mb ahead of the approaching front=20
with the potential for upscale/organized growth into one or more=20
MCSs. The storm/mesoscale nature of the threat leads to uncertainty
of a more focused corridor of higher risk, but a Slight Risk may=20
be necessary particularly over the Upper Mississippi Valley if=20
trends remain consistent in the guidance.=20

...Northeast...

There continues to be an increasing concern for heavy to=20
potentially excessive rainfall to develop across western=20
Pennsylvania and surrounding areas as the frontal boundary sags=20
southward and taps into the pooled PW values of 1.5-2". The latest=20
model guidance are showing local maximums upwards of 2 inches=20
possible and the ERO first guess supports expanding the Marginal=20
Risk from eastern Pennsylvania further west into eastern Ohio, West
Virginia and western Maryland. Further north, widespread=20
convective activity across southeastern Canada north of the warm=20
front looks to move into portions of northern New England. While=20
guidance indicates the potential for 1-2" of rainfall totals across
the region, the less robust convection on the northern side of the
front should keep any flooding issues isolated.=20

...Southeast to the Mississippi Valley and adjacent southern=20
Plains...

Similar to day 1, scattered pulse thunderstorms are expected=20
across a broad warm sector as seasonable instability develops with=20
daytime heating from the Southeast west through the Mississippi=20
Valley and into the adjacent southern Plains. High precipitable=20
water values (~2", 2 standard deviations above the mean) will once=20
again lead to highly efficient rain rates of 1-2" per hour,=20
possibly as high as 3" per hour, which is more than enough to lead=20
to isolated flash flooding concerns despite the generally limited=20 thunderstorm duration.=20

...New Mexico...

Yet another day of thunderstorms is expected across portions of=20
southern New Mexico and west Texas with locally heavy rainfall=20
(1-2") possible. QPF trends (coverage, intensity) are more isolated
compared to day 1 with the moist south to southeast low-level=20
upslope flow likely resulting in more localized areas of heavier=20
rainfall focused across the Sacramento and Guadalupe Mtns south=20
through the Trans-Pecos. The flash flood potential is expected to=20
remain isolated.

Putnam/Bann

Day 3
Valid 12Z Sun Jun 29 2025 - 12Z Mon Jun 30 2025

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL EXTENDING OVER=20
PORTIONS OF THE CENTRAL UNITED STATES...

There is a Marginal Risk of excessive rainfall over portions of=20
the central United States from the western Great Lakes south=20
through the Mississippi Valley and west into the central/southern=20
Plains and southern Rockies. Showers and thunderstorms are expected
both along and well-ahead of a cold front and trailing surface=20 trough/dryline as an upper-level trough approaches from the west.=20
Mechanisms to help focus convection becomes less defined ahead of=20
the front but deterministic guidance indicates widely scattered=20
rainfall totals of 1-3" are possible in an atmosphere characterized
by precipitable water values in excess of 1.5 inches over all but=20
the plains near the Central and Southern Rockies to in excess of 2=20
inches east of the Mississippi. Surface waves along the front may=20
help to focus/organize convection and lead to a more concentrated=20
threat. This is supported by localized maxima in the ensemble=20 means/probabilities in the central Plains/Missouri Valley to the=20
Upper Mississippi Valley region, but with low confidence in exact=20
location at this point. Therefore, a broad Marginal Risk has been=20
maintained for now.=20

Putnam/Bann


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!_OcpklmbKp4bvgwOz8z14gY748kjhwb4AyRsVFtpntuX= ZV_SCDDlNQplgNHfGvWipKKiYVW3oy0bgjgd65W8zCFVZh8$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!_OcpklmbKp4bvgwOz8z14gY748kjhwb4AyRsVFtpntuX= ZV_SCDDlNQplgNHfGvWipKKiYVW3oy0bgjgd65W8VN2EMIw$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!_OcpklmbKp4bvgwOz8z14gY748kjhwb4AyRsVFtpntuX= ZV_SCDDlNQplgNHfGvWipKKiYVW3oy0bgjgd65W8dmj346s$=20

=3D =3D =3D
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FOUS30 KWBC 280037
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
837 PM EDT Fri Jun 27 2025

Day 1
Valid 01Z Sat Jun 28 2025 - 12Z Sat Jun 28 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL IN AND NEAR
SOUTHWEST VIRGINIA...

...Central & Southern Appalachians...
A thunderstorm/heavy rainfall threat has become more focused as of
late as very moist flow interacts with the terrain near a 'back-=20
door' cold front which is stalling across the region. Earlier=20
storms across West Virgina sent outflow boundaries down the front=20
to help with the consolidation in southwest Virginia. Efficient=20
hourly amounts up to 3" are possible in the very near term given=20
PWATs upwards of 2". Much of this region remains more sensitive to
additional rainfall not only due to the typical terrain impacts=20
but a number of recent heavy rainfall events keeping FFGs low, with
scattered to potentially numerous instances of flash flooding=20
possible. To the southwest, ongoing thunderstorms down the=20
foothills of the Appalachians into the AL Piedmont pose a Marginal
Risk of excessive rainfall before CIN sets in later tonight. The
Gulf coasts of AL & MS pose a similar risk during the early morning
hours on Saturday due to onshore flow from the warm Gulf. Pulse-=20
type thunderstorms will have the ability to produce quick efficient
bursts of heavy rainfall (1-3") and the risk for some mostly=20
isolated urban flooding, especially where any storms=20
develop/congeal along residual outflows.


...Northern Plains...
A quick-moving shortwave across the northern tier of the country=20
is starting to lead to thunderstorm activity capable of locally=20
heavy rainfall, especially if convection can grow upscale into a=20
more organized MCS. However, prospects for flash flooding still=20
seem to be limited given the progressive nature of the shortwave=20 trough/possible MCS as noted in the 18z HREF probabilities of 0.5"+
of rain in an hour. A quick 1-3+" is likely anywhere over parts of
the eastern Dakotas and across central Minnesota.


...In and near Oklahoma & Arkansas...=20
A couple rounds of convection -- one ongoing with an additional=20
flare up overnight in and near existing outflow boundaries near the
Red River of the South and AR -- continue the need for a Marginal=20
Risk of excessive rainfall/flash flooding in and near portions of=20
eastern OK and AR through tonight. Hourly rain amounts to 2.5"=20
would be problematic in sensitive terrain and in urban areas.

Roth


Day 2
Valid 12Z Sat Jun 28 2025 - 12Z Sun Jun 29 2025

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS
OF THE NORTHERN PLAINS AND UPPER MIDWEST, THE NORTHEAST, AND SOUTH-
CENTRAL NEW MEXICO...

...Northern Plains and Upper Midwest...

Next approaching upper shortwave trough, with a 90kt upper level
jet streak on the lee side, will generate a compact area of fairly
robust, transient deep-layer forcing over the outlook area into
Saturday night. MUCAPEs are expected to soar within the warm sector
prior to the surface cold frontal passage. Given precipitable
water values getting near 1.75 inches...storms which form within
the unstable airmass will be capable of producing rainfall rates in
excess of 1 inch per hour and areal average rainfall amounts of 1
to 3 inches...especially once low- level inflow accelerates to
between 30 kts and 40kts at 850 mb ahead of the approaching front
with the potential for upscale/organized growth into one or more
MCSs. The storm/mesoscale nature of the threat leads to uncertainty
of a more focused corridor of higher risk, but a Slight Risk may
be necessary particularly over the Upper Mississippi Valley if
trends remain consistent in the guidance.

...Northeast...

There continues to be an increasing concern for heavy to
potentially excessive rainfall to develop across western
Pennsylvania and surrounding areas as the frontal boundary sags
southward and taps into the pooled PW values of 1.5-2". The latest
model guidance are showing local maximums upwards of 2 inches
possible and the ERO first guess supports expanding the Marginal
Risk from eastern Pennsylvania further west into eastern Ohio, West
Virginia and western Maryland. Further north, widespread
convective activity across southeastern Canada north of the warm
front looks to move into portions of northern New England. While
guidance indicates the potential for 1-2" of rainfall totals across
the region, the less robust convection on the northern side of the
front should keep any flooding issues isolated.

...Southeast to the Mississippi Valley and adjacent southern
Plains...

Similar to day 1, scattered pulse thunderstorms are expected
across a broad warm sector as seasonable instability develops with
daytime heating from the Southeast west through the Mississippi
Valley and into the adjacent southern Plains. High precipitable
water values (~2", 2 standard deviations above the mean) will once
again lead to highly efficient rain rates of 1-2" per hour,
possibly as high as 3" per hour, which is more than enough to lead
to isolated flash flooding concerns despite the generally limited
thunderstorm duration.

...New Mexico...

Yet another day of thunderstorms is expected across portions of
southern New Mexico and west Texas with locally heavy rainfall
(1-2") possible. QPF trends (coverage, intensity) are more isolated
compared to day 1 with the moist south to southeast low-level
upslope flow likely resulting in more localized areas of heavier
rainfall focused across the Sacramento and Guadalupe Mtns south
through the Trans-Pecos. The flash flood potential is expected to
remain isolated.

Putnam/Bann

Day 3
Valid 12Z Sun Jun 29 2025 - 12Z Mon Jun 30 2025

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL EXTENDING OVER
PORTIONS OF THE CENTRAL UNITED STATES...

There is a Marginal Risk of excessive rainfall over portions of
the central United States from the western Great Lakes south
through the Mississippi Valley and west into the central/southern
Plains and southern Rockies. Showers and thunderstorms are expected
both along and well-ahead of a cold front and trailing surface
trough/dryline as an upper-level trough approaches from the west.
Mechanisms to help focus convection becomes less defined ahead of
the front but deterministic guidance indicates widely scattered
rainfall totals of 1-3" are possible in an atmosphere characterized
by precipitable water values in excess of 1.5 inches over all but
the plains near the Central and Southern Rockies to in excess of 2
inches east of the Mississippi. Surface waves along the front may
help to focus/organize convection and lead to a more concentrated
threat. This is supported by localized maxima in the ensemble means/probabilities in the central Plains/Missouri Valley to the
Upper Mississippi Valley region, but with low confidence in exact
location at this point. Therefore, a broad Marginal Risk has been
maintained for now.

Putnam/Bann


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!9k_7878JXZq0tXxjek2i7rlPtiFabObuSV1nd2S8YBPu= Kj9YhvMVYaV92nTFscCz3WPfu-G74s1t9aHk62eWi1Mdo4w$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!9k_7878JXZq0tXxjek2i7rlPtiFabObuSV1nd2S8YBPu= Kj9YhvMVYaV92nTFscCz3WPfu-G74s1t9aHk62eWI3VO-28$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!9k_7878JXZq0tXxjek2i7rlPtiFabObuSV1nd2S8YBPu= Kj9YhvMVYaV92nTFscCz3WPfu-G74s1t9aHk62eWQIeWfg0$=20

=3D =3D =3D
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FOUS30 KWBC 280829
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
429 AM EDT Sat Jun 28 2025

Day 1
Valid 12Z Sat Jun 28 2025 - 12Z Sun Jun 29 2025

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS=20
OF THE PLAINS INTO THE MID ATLANTIC/NORTHEAST US...

...Northern Plains and Upper Midwest...

Showers and thunderstorms capable of producing locally heavy=20
rainfall rates and heavy rainfall totals have the potential to
produce flash flooding as the next upper shortwave trough
approaches. Aided by a 90kt upper level jet streak on the lee=20
side...the upper trough will generate a compact area of fairly=20
robust, transient deep-layer forcing over the outlook area later
today and tonight. MUCAPEs are expected to soar within the warm=20
sector prior to the surface cold frontal passage. Given=20
precipitable water values getting near 1.75 inches...storms which=20
form within the unstable airmass will be capable of producing=20
rainfall rates in excess 1.5 inches per hour and areal average=20
rainfall amounts of 1 to 3 inches...especially once low- level=20
inflow accelerates to between 30 kts and 40kts at 850 mb ahead of=20
the approaching front. The storm/mesoscale nature of the threat=20
leads to uncertainty of a more focused corridor of higher risk, but
a Slight Risk may still be necessary...particularly over the Upper
Mississippi Valley...if trends remain consistent.

...Mississippi Valley to the Mid Atlantic/Northeast...

There continues to be an increasing concern for heavy to
potentially excessive rainfall to develop across western
Pennsylvania and surrounding areas as the frontal boundary sags
southward and taps into the pooled PW values of 1.5-2 inches and as
weak mid-level shortwave energy aids convective development in a
high CAPE/weak flow environment over portions of the Mid-
Mississippi Valley into the upper Ohio Valley. Farther north,=20
maintained the Marginal Risk to account for the possibility that
some of the convective activity across southeastern Canada north=20
of the warm front clips portions of northern New England. While=20
guidance indicates the potential for 1-2" of rainfall totals across
the region, the less robust convection on the northern side of the
front should keep any flooding issues isolated.

...Southeast to adjacent southern Plains...

Scattered pulse thunderstorms are expected across a broad warm=20
sector as seasonable instability develops with daytime heating from
the Southeast and into the adjacent southern Plains. High=20
precipitable water values (at or above 2 inches, some 2 standard=20
deviations above the climatological mean for this time of year)=20
will once again lead to highly efficient rain rates of 1-2" per=20
hour, possibly as high as 3" per hour, which is more than enough to
lead to isolated flash flooding concerns despite the generally=20
limited thunderstorm duration. With a signal that has persisted
several runs...introduced a Marginal risk area over parts of the
Florida peninsula for late day convection that fires along a weak
convergence boundary.

...New Mexico...

Yet another day of thunderstorms is expected across portions of
southern New Mexico and west Texas with locally heavy rainfall
(1-2") possible. QPF trends (coverage, intensity) are more isolated
compared to day 1 with the moist south to southeast low-level
upslope flow likely resulting in more localized areas of heavier
rainfall focused across the Sacramento and Guadalupe Mtns south
through the Trans-Pecos. The flash flood potential is expected to
remain isolated.

Bann/Putnam

Day 2
Valid 12Z Sun Jun 29 2025 - 12Z Mon Jun 30 2025

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL EXTENDING OVER=20
PORTIONS OF THE CENTRAL UNITED STATES...

There is a Marginal Risk of excessive rainfall over portions of
the central United States from the western Great Lakes south
through the Mississippi Valley and west into the central/southern
Plains and southern Rockies. Showers and thunderstorms are expected
both along and well-ahead of a cold front and trailing surface
trough/dryline as an upper-level trough approaches from the west.
Mechanisms to help focus convection becomes less defined ahead of
the front but deterministic guidance indicates widely scattered
rainfall totals of 1-3" are possible in an atmosphere characterized
by precipitable water values in excess of 1.5 inches over all but
the plains near the Central and Southern Rockies to in excess of 2
inches east of the Mississippi.=20

Waves propagating along the front may help to focus/organize=20
convection and lead to a more concentrated threat...and remained=20
supported by localized maxima in the ensemble means/probabilities=20
in the central Plains/Missouri Valley to the Upper Mississippi=20
Valley region...confidence remained low with respect to the exact=20
placement. Bann/Putnam

Bann

Day 3
Valid 12Z Mon Jun 30 2025 - 12Z Tue Jul 01 2025

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS
OF THE WESTERN PLAINS EASTWARD INTO THE MID ATLANTIC...

Similar to Sunday...convection is expected to develop within a region
of decent CAPE and precipitable water values in excess of 2=20
standard deviations above climatology. Except for some mid-level
westerly flow around the Great Lakes to provide some shear
there...the flow farther south should be fairly meager (but offset
by steeper low-level lapse rates). This sets up the potential for=20
some local rainfall rates in excess of 1 inch per hour that results
in excessive rainfall from the Western High Plains=20
east/northeastward into the Ohio Valley and parts of the Mid-
Atlantic region on Monday and Monday night. A weakening surface=20
boundary will help focus some of the threat for heavier rainfall=20
but its placement is quite uncertain. Without much forcing or
confidence in placement of a boundary to focus activity...placement
of any heavy rainfall is low confidence.

Bann


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!8AHabBRIwEOgRDFGByiIaYEekjsrgCrp489nLtt87VDz= NWfi_wj1YceW-w8aaHiIFP03xf3-cC0I5frlNjy4q7Fir3I$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!8AHabBRIwEOgRDFGByiIaYEekjsrgCrp489nLtt87VDz= NWfi_wj1YceW-w8aaHiIFP03xf3-cC0I5frlNjy41L9L5y4$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!8AHabBRIwEOgRDFGByiIaYEekjsrgCrp489nLtt87VDz= NWfi_wj1YceW-w8aaHiIFP03xf3-cC0I5frlNjy4OoelV7o$=20

=3D =3D =3D
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FOUS30 KWBC 281556
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
1156 AM EDT Sat Jun 28 2025

Day 1
Valid 16Z Sat Jun 28 2025 - 12Z Sun Jun 29 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS OF SOUTH-CENTRAL MISSOURI AND NORTH-CENTRAL ARKANSAS...


...Middle/Lower Mississippi Valley and adjacent southern Plains,=20
Ohio and Tennessee valleys...

Firmly in the warm sector and within a moist airmass containing
widespread PWATs of 1.8-2.2" (near the 90th climatological
percentile), isolated to scattered flash flooding is possible=20
today with a potentially higher focus across parts of southern MO=20
and northern AR tonight, where a Slight Risk of Excessive Rainfall=20
was introduced in the 16z update. An MCV evident on morning radar=20
and satellite imagery has already prompted a few FFWs across=20
eastern OK and KS while gradually pushing eastward. This feature=20
will aid in sparking widely scattered slow- moving thunderstorms=20
throughout the afternoon while instability levels rise due to=20
diurnal heating. Pulse thunderstorms within weak steering flow and
an unstable/moist environment are also likely through much of the=20
Ohio and Tennessee valleys today, with smaller scale scattered=20
flash flooding possible. Current trends are for the aforementioned=20
MCV to make it into the vicinity of southeast MO by late tonight=20
and influence a sharp mid-level trough ahead of increasing warm air
advection throughout the Plains due to a crossing shortwave in the
north- central U.S. and the nighttime low- level jet. CAMs still=20
differ somewhat in the exact location of a potential northwest-=20
southeast oriented band of slow-moving storms, but generally=20
converge on south-central MO and don't really develop until around=20
09z tonight. The 12z HREF has increased 24-hr probs (12z Sat-12z=20
Sun) for greater than 5" of rain to 30-45% within the Slight Risk=20
outline. Additionally, this part of the country also has relatively
saturated soils already (70-100% 0-40 cm below ground relative=20
soil moisture percentiles per NASA SPoRT) not including the=20
likelihood of scattered thunderstorms and potentially overlapping=20
heavy rainfall this afternoon.

...Northern Plains and Upper Midwest...

Showers and thunderstorms capable of producing locally heavy
rainfall rates and heavy rainfall totals have the potential to
produce flash flooding as the next upper shortwave trough
approaches the north-central United States. Aided by a 90kt upper=20
level jet streak on the lee side...the upper trough will generate a
compact area of fairly robust, transient deep-layer forcing over=20
the outlook area later today and tonight. MUCAPEs are expected to=20
soar within the warm sector prior to the surface cold frontal=20
passage late tonight. Given precipitable water values getting near
1.75 inches...storms which form within the unstable airmass will=20
be capable of producing rainfall rates in excess 1.5"/hr and areal=20
average rainfall amounts of 1 to 3 inches...especially once low-=20
level inflow accelerates to between 30 kts and 40kts at 850 mb=20
ahead of the approaching front. The storm/mesoscale nature of the=20
threat leads to uncertainty of a more focused corridor of higher=20
risk, but a Slight Risk was considered in central MN where forward
propagation of storms may begin slow this evening and is reinforced
by the highest 12z HREF probs (20-30%) for exceeding 3" in 6 hours.

...Central Appalachians to the Northeast...

There continues to be a concern for heavy to potentially excessive
rainfall to develop across western Pennsylvania and surrounding=20
areas as the frontal boundary sags southward and taps into the=20
pooled PW values of 1.5-2". 12z CAMs are not a robust with rainfall
amounts in the central Appalachians and keep things moving along in
the Northeast to limit any flash flooding to isolated instances.
However, the environment remains unstable and moist, so any slow-=20
moving storms could lead to forming mesoscale boundaries that=20
create locally intense rainfall. Farther north, the Marginal Risk=20
was removed across northern New England given unimpressive radar=20
trends this morning and a more progressive patter. Still, 1-1.5" of
rainfall could lead to very isolated and more nuisance flooding.

...Southeast and central Florida Peninsula...

Scattered pulse thunderstorms are expected across a broad warm
sector and near an upper trough lingering over the region as=20
seasonable instability develops with daytime heating. A greater
focus for intense rainfall also overlaps with higher FFG across=20
the central Gulf Coast and Florida Peninsula, where rainfall rates
of 2-3"/hr are possible but should weaken quickly before=20
convection is driven off outflow from numerous other pop-up storms.

...New Mexico...

Yet another day of thunderstorms is expected across portions of
southern New Mexico and west Texas with locally heavy rainfall
(1-2") possible. QPF trends (coverage, intensity) are more isolated
compared prior days with the moist south to southeast low-level=20
upslope flow likely resulting in more localized areas of heavier=20
rainfall focused across the Sacramento and Guadalupe Mtns south=20
through the Trans-Pecos. The flash flood potential is expected to=20
remain isolated.

Snell

Day 2
Valid 12Z Sun Jun 29 2025 - 12Z Mon Jun 30 2025

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL EXTENDING OVER
PORTIONS OF THE CENTRAL UNITED STATES...

There is a Marginal Risk of excessive rainfall over portions of
the central United States from the western Great Lakes south
through the Mississippi Valley and west into the central/southern
Plains and southern Rockies. Showers and thunderstorms are expected
both along and well-ahead of a cold front and trailing surface
trough/dryline as an upper-level trough approaches from the west.
Mechanisms to help focus convection becomes less defined ahead of
the front but deterministic guidance indicates widely scattered
rainfall totals of 1-3" are possible in an atmosphere characterized
by precipitable water values in excess of 1.5 inches over all but
the plains near the Central and Southern Rockies to in excess of 2
inches east of the Mississippi.

Waves propagating along the front may help to focus/organize
convection and lead to a more concentrated threat...and remained
supported by localized maxima in the ensemble means/probabilities
in the central Plains/Missouri Valley to the Upper Mississippi
Valley region...confidence remained low with respect to the exact
placement. Bann/Putnam

Bann

Day 3
Valid 12Z Mon Jun 30 2025 - 12Z Tue Jul 01 2025

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS
OF THE WESTERN PLAINS EASTWARD INTO THE MID ATLANTIC...

Similar to Sunday...convection is expected to develop within a region
of decent CAPE and precipitable water values in excess of 2
standard deviations above climatology. Except for some mid-level
westerly flow around the Great Lakes to provide some shear
there...the flow farther south should be fairly meager (but offset
by steeper low-level lapse rates). This sets up the potential for
some local rainfall rates in excess of 1 inch per hour that results
in excessive rainfall from the Western High Plains
east/northeastward into the Ohio Valley and parts of the Mid-
Atlantic region on Monday and Monday night. A weakening surface
boundary will help focus some of the threat for heavier rainfall
but its placement is quite uncertain. Without much forcing or
confidence in placement of a boundary to focus activity...placement
of any heavy rainfall is low confidence.

Bann


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!9g6ErAp_JVsBJepxzG8CEM3yCRT_xZywhATijZIox04r= TRsvGu5Nek1Ru6WcIB4mNE6C6N2u8pv63M6uGPif8XtGT44$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!9g6ErAp_JVsBJepxzG8CEM3yCRT_xZywhATijZIox04r= TRsvGu5Nek1Ru6WcIB4mNE6C6N2u8pv63M6uGPif0HrwxP4$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!9g6ErAp_JVsBJepxzG8CEM3yCRT_xZywhATijZIox04r= TRsvGu5Nek1Ru6WcIB4mNE6C6N2u8pv63M6uGPifdinHFOs$=20

=3D =3D =3D
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FOUS30 KWBC 281925
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
325 PM EDT Sat Jun 28 2025

Day 1
Valid 1912Z Sat Jun 28 2025 - 12Z Sun Jun 29 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS OF SOUTH-CENTRAL MISSOURI AND NORTH-CENTRAL ARKANSAS...


19Z Special Update...=20
Extended the Marginal Risk farther east across central, into=20
eastern North Carolina. PWs ~1.9 inches, along with SBCAPE=20
2500-3000 J/kg and weak flow aloft are supporting slow-moving=20
storm with heavy rates (up to 2+ inches/hr in some of the stronger=20
cells). This has resulted in areas of flash flooding in central=20
North Carolina. The 18Z RAP indicates the environment will remain=20
favorable for heavy rain, with additional increases in PWs and CAPE
into the evening.

Pereira

...Middle/Lower Mississippi Valley and adjacent southern Plains,
Ohio and Tennessee valleys...

Firmly in the warm sector and within a moist airmass containing
widespread PWATs of 1.8-2.2" (near the 90th climatological
percentile), isolated to scattered flash flooding is possible
today with a potentially higher focus across parts of southern MO
and northern AR tonight, where a Slight Risk of Excessive Rainfall
was introduced in the 16z update. An MCV evident on morning radar
and satellite imagery has already prompted a few FFWs across
eastern OK and KS while gradually pushing eastward. This feature
will aid in sparking widely scattered slow- moving thunderstorms
throughout the afternoon while instability levels rise due to
diurnal heating. Pulse thunderstorms within weak steering flow and
an unstable/moist environment are also likely through much of the
Ohio and Tennessee valleys today, with smaller scale scattered
flash flooding possible. Current trends are for the aforementioned
MCV to make it into the vicinity of southeast MO by late tonight
and influence a sharp mid-level trough ahead of increasing warm air
advection throughout the Plains due to a crossing shortwave in the
north- central U.S. and the nighttime low- level jet. CAMs still
differ somewhat in the exact location of a potential northwest-
southeast oriented band of slow-moving storms, but generally
converge on south-central MO and don't really develop until around
09z tonight. The 12z HREF has increased 24-hr probs (12z Sat-12z
Sun) for greater than 5" of rain to 30-45% within the Slight Risk
outline. Additionally, this part of the country also has relatively
saturated soils already (70-100% 0-40 cm below ground relative
soil moisture percentiles per NASA SPoRT) not including the
likelihood of scattered thunderstorms and potentially overlapping
heavy rainfall this afternoon.

...Northern Plains and Upper Midwest...

Showers and thunderstorms capable of producing locally heavy
rainfall rates and heavy rainfall totals have the potential to
produce flash flooding as the next upper shortwave trough
approaches the north-central United States. Aided by a 90kt upper
level jet streak on the lee side...the upper trough will generate a
compact area of fairly robust, transient deep-layer forcing over
the outlook area later today and tonight. MUCAPEs are expected to
soar within the warm sector prior to the surface cold frontal
passage late tonight. Given precipitable water values getting near
1.75 inches...storms which form within the unstable airmass will
be capable of producing rainfall rates in excess 1.5"/hr and areal
average rainfall amounts of 1 to 3 inches...especially once low-
level inflow accelerates to between 30 kts and 40kts at 850 mb
ahead of the approaching front. The storm/mesoscale nature of the
threat leads to uncertainty of a more focused corridor of higher
risk, but a Slight Risk was considered in central MN where forward
propagation of storms may begin slow this evening and is reinforced
by the highest 12z HREF probs (20-30%) for exceeding 3" in 6 hours.

...Central Appalachians to the Northeast...

There continues to be a concern for heavy to potentially excessive
rainfall to develop across western Pennsylvania and surrounding
areas as the frontal boundary sags southward and taps into the
pooled PW values of 1.5-2". 12z CAMs are not a robust with rainfall
amounts in the central Appalachians and keep things moving along in
the Northeast to limit any flash flooding to isolated instances.
However, the environment remains unstable and moist, so any slow-
moving storms could lead to forming mesoscale boundaries that
create locally intense rainfall. Farther north, the Marginal Risk
was removed across northern New England given unimpressive radar
trends this morning and a more progressive patter. Still, 1-1.5" of
rainfall could lead to very isolated and more nuisance flooding.

...Southeast and central Florida Peninsula...

Scattered pulse thunderstorms are expected across a broad warm
sector and near an upper trough lingering over the region as
seasonable instability develops with daytime heating. A greater
focus for intense rainfall also overlaps with higher FFG across
the central Gulf Coast and Florida Peninsula, where rainfall rates
of 2-3"/hr are possible but should weaken quickly before
convection is driven off outflow from numerous other pop-up storms.

...New Mexico...

Yet another day of thunderstorms is expected across portions of
southern New Mexico and west Texas with locally heavy rainfall
(1-2") possible. QPF trends (coverage, intensity) are more isolated
compared prior days with the moist south to southeast low-level
upslope flow likely resulting in more localized areas of heavier
rainfall focused across the Sacramento and Guadalupe Mtns south
through the Trans-Pecos. The flash flood potential is expected to
remain isolated.

Snell

Day 2
Valid 12Z Sun Jun 29 2025 - 12Z Mon Jun 30 2025

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL EXTENDING OVER
PORTIONS OF THE CENTRAL UNITED STATES...

There is a Marginal Risk of excessive rainfall over portions of
the central United States from the western Great Lakes south
through the Mississippi Valley and west into the central/southern
Plains and southern Rockies. Showers and thunderstorms are expected
both along and well-ahead of a cold front and trailing surface
trough/dryline as an upper-level trough approaches from the west.
Mechanisms to help focus convection becomes less defined ahead of
the front but deterministic guidance indicates widely scattered
rainfall totals of 1-3" are possible in an atmosphere characterized
by precipitable water values in excess of 1.5 inches over all but
the plains near the Central and Southern Rockies to in excess of 2
inches east of the Mississippi.

Waves propagating along the front may help to focus/organize
convection and lead to a more concentrated threat...and remained
supported by localized maxima in the ensemble means/probabilities
in the central Plains/Missouri Valley to the Upper Mississippi
Valley region...confidence remained low with respect to the exact
placement. Bann/Putnam

Bann

Day 3
Valid 12Z Mon Jun 30 2025 - 12Z Tue Jul 01 2025

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS
OF THE WESTERN PLAINS EASTWARD INTO THE MID ATLANTIC...

Similar to Sunday...convection is expected to develop within a region
of decent CAPE and precipitable water values in excess of 2
standard deviations above climatology. Except for some mid-level
westerly flow around the Great Lakes to provide some shear
there...the flow farther south should be fairly meager (but offset
by steeper low-level lapse rates). This sets up the potential for
some local rainfall rates in excess of 1 inch per hour that results
in excessive rainfall from the Western High Plains
east/northeastward into the Ohio Valley and parts of the Mid-
Atlantic region on Monday and Monday night. A weakening surface
boundary will help focus some of the threat for heavier rainfall
but its placement is quite uncertain. Without much forcing or
confidence in placement of a boundary to focus activity...placement
of any heavy rainfall is low confidence.

Bann


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!5dsvhfxCc12Kra4hEdCPTr6JopFRZG2TYv2-6PiEwrmv= ZM2yLLDjMFqILWJshZNBptoCBt4PPAcDfwxNdlCCC2I6fp0$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!5dsvhfxCc12Kra4hEdCPTr6JopFRZG2TYv2-6PiEwrmv= ZM2yLLDjMFqILWJshZNBptoCBt4PPAcDfwxNdlCCyQWJslA$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!5dsvhfxCc12Kra4hEdCPTr6JopFRZG2TYv2-6PiEwrmv= ZM2yLLDjMFqILWJshZNBptoCBt4PPAcDfwxNdlCCUHpBa0U$=20

=3D =3D =3D
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FOUS30 KWBC 281952
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
352 PM EDT Sat Jun 28 2025

Day 1
Valid 16Z Sat Jun 28 2025 - 12Z Sun Jun 29 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS OF SOUTH-CENTRAL MISSOURI AND NORTH-CENTRAL ARKANSAS...

19Z Special Update...=20
Extended the Marginal Risk farther east across central, into
eastern North Carolina. PWs ~1.9 inches, along with SBCAPE
2500-3000 J/kg and weak flow aloft are supporting slow-moving storm
with heavy rates (up to 2+ inches/hr in some of the stronger
cells). This has resulted in areas of flash flooding in central
North Carolina. The 18Z RAP indicates the environment will remain
favorable for heavy rain, with additional increases in PWs and CAPE
into the evening.

Pereira

...Middle/Lower Mississippi Valley and adjacent southern=20
Plains, Ohio and Tennessee valleys...

Firmly in the warm sector and within a moist airmass containing
widespread PWATs of 1.8-2.2" (near the 90th climatological
percentile), isolated to scattered flash flooding is possible
today with a potentially higher focus across parts of southern MO
and northern AR tonight, where a Slight Risk of Excessive Rainfall
was introduced in the 16z update. An MCV evident on morning radar
and satellite imagery has already prompted a few FFWs across
eastern OK and KS while gradually pushing eastward. This feature
will aid in sparking widely scattered slow- moving thunderstorms
throughout the afternoon while instability levels rise due to
diurnal heating. Pulse thunderstorms within weak steering flow and
an unstable/moist environment are also likely through much of the
Ohio and Tennessee valleys today, with smaller scale scattered
flash flooding possible. Current trends are for the aforementioned
MCV to make it into the vicinity of southeast MO by late tonight
and influence a sharp mid-level trough ahead of increasing warm air
advection throughout the Plains due to a crossing shortwave in the
north- central U.S. and the nighttime low- level jet. CAMs still
differ somewhat in the exact location of a potential northwest-
southeast oriented band of slow-moving storms, but generally
converge on south-central MO and don't really develop until around
09z tonight. The 12z HREF has increased 24-hr probs (12z Sat-12z
Sun) for greater than 5" of rain to 30-45% within the Slight Risk
outline. Additionally, this part of the country also has relatively
saturated soils already (70-100% 0-40 cm below ground relative
soil moisture percentiles per NASA SPoRT) not including the
likelihood of scattered thunderstorms and potentially overlapping
heavy rainfall this afternoon.

...Northern Plains and Upper Midwest...

Showers and thunderstorms capable of producing locally heavy
rainfall rates and heavy rainfall totals have the potential to
produce flash flooding as the next upper shortwave trough
approaches the north-central United States. Aided by a 90kt upper
level jet streak on the lee side...the upper trough will generate a
compact area of fairly robust, transient deep-layer forcing over
the outlook area later today and tonight. MUCAPEs are expected to
soar within the warm sector prior to the surface cold frontal
passage late tonight. Given precipitable water values getting near
1.75 inches...storms which form within the unstable airmass will
be capable of producing rainfall rates in excess 1.5"/hr and areal
average rainfall amounts of 1 to 3 inches...especially once low-
level inflow accelerates to between 30 kts and 40kts at 850 mb
ahead of the approaching front. The storm/mesoscale nature of the
threat leads to uncertainty of a more focused corridor of higher
risk, but a Slight Risk was considered in central MN where forward
propagation of storms may begin slow this evening and is reinforced
by the highest 12z HREF probs (20-30%) for exceeding 3" in 6 hours.

...Central Appalachians to the Northeast...

There continues to be a concern for heavy to potentially excessive
rainfall to develop across western Pennsylvania and surrounding
areas as the frontal boundary sags southward and taps into the
pooled PW values of 1.5-2". 12z CAMs are not a robust with rainfall
amounts in the central Appalachians and keep things moving along in
the Northeast to limit any flash flooding to isolated instances.
However, the environment remains unstable and moist, so any slow-
moving storms could lead to forming mesoscale boundaries that
create locally intense rainfall. Farther north, the Marginal Risk
was removed across northern New England given unimpressive radar
trends this morning and a more progressive patter. Still, 1-1.5" of
rainfall could lead to very isolated and more nuisance flooding.

...Southeast and central Florida Peninsula...

Scattered pulse thunderstorms are expected across a broad warm
sector and near an upper trough lingering over the region as
seasonable instability develops with daytime heating. A greater
focus for intense rainfall also overlaps with higher FFG across
the central Gulf Coast and Florida Peninsula, where rainfall rates
of 2-3"/hr are possible but should weaken quickly before
convection is driven off outflow from numerous other pop-up storms.

...New Mexico...

Yet another day of thunderstorms is expected across portions of
southern New Mexico and west Texas with locally heavy rainfall
(1-2") possible. QPF trends (coverage, intensity) are more isolated
compared prior days with the moist south to southeast low-level
upslope flow likely resulting in more localized areas of heavier
rainfall focused across the Sacramento and Guadalupe Mtns south
through the Trans-Pecos. The flash flood potential is expected to
remain isolated.

Snell

Day 2
Valid 12Z Sun Jun 29 2025 - 12Z Mon Jun 30 2025

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL EXTENDING FROM
PORTIONS OF THE CENTRAL UNITED STATES TO THE CENTRAL GULF COAST AND MID-ATLANTIC...

Late-June weather pattern remains in place on Sunday with widely
scattered showers/storms and isolated chances for flash flooding
within the warm and humid airmass spanning from the central U.S. to
the Southeast and Mid-Atlantic. Showers and thunderstorms are=20
expected both along and well- ahead of a cold front sinking
southeastward across the central Plains and Midwest, as well as
associated with diurnal monsoon activity across the southern
Rockies and adjacent High Plains. At the start of day 2, there's
the potential for ongoing late-night convection across south-=20
central MO as a remnant MCV and overnight low-level jet foster
slow-moving thunderstorms. There remains rather high uncertainty
regarding the maintenance of thunderstorm activity in this region
past the 12z Sun start time of Day 2, but should greater certainty
arise a Slight Risk may be needed for south-central MO and nearby
regions.

Meanwhile, organized convection firing along the advancing cold
front across the central Plains and Midwest should provide another
focus for potential slow-moving convection in the evening before
activity should become more progressive under the influence of a
strengthening cold pool and progressive cold front. PWs approaching
2" and near the 90th climatological percentile will provide the
opportunity for intense rainfall rates scattered 2-4" rainfall
totals between parts of KS, MO, and southern IA.

Elsewhere within the warm sector across the Mid-South, Mid-
Atlantic, Southeast, and Southern Rockies/High Plains, typical
summer thunderstorms exhibiting scattered and a pulse mode are
likely. These storms may contain briefly very intense rainfall
rates, but see updrafts collapse quickly and become outflow
dependent. Where convective clusters merge or linger near a
stationary front draped across the Mid-Atlantic and central
Appalachians, isolated flash flooding is possible.=20

Snell/Bann

Day 3
Valid 12Z Mon Jun 30 2025 - 12Z Tue Jul 01 2025

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS
OF THE SOUTHERN ROCKIES EASTWARD INTO THE MID ATLANTIC...

Similar to Sunday...convection is expected to develop within a region
of decent CAPE and precipitable water values in excess of 2
standard deviations above climatology. Except for some mid-level
westerly flow around the Great Lakes to provide some shear
there...the flow farther south should be fairly meager (but offset
by steeper low-level lapse rates). This sets up the potential for
some local rainfall rates in excess of 1 inch per hour that results
in excessive rainfall from the Southern Rockies/Western High=20
Plains east/northeastward into the Ohio Valley and parts of the=20
Mid- Atlantic region on Monday and Monday night. A weakening=20
surface boundary will help focus some of the threat for heavier=20
rainfall but its placement is quite uncertain. One area at the
moment that is being monitored for a potential upgrade to a Slight
Risk are parts of the Upper Ohio Valley and central Appalachians
(centered over western PA). The synoptic setup with a
stationary/warm front stretching across southern PA and an
approaching cold front from the west should help foster greater
coverage in showers/storms within a moist environment, but storm=20
motions within a mean column wind of 30kts could limit the=20
flooding threat even though this area remains sensitive to intense=20
rainfall. Therefor, a Marginal Risk was maintained to highlight the
threat for isolated flash flooding.

Snell/Bann


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!8eEFGH4vyGJNUkN5THSby62KPT7I_FgxPS2lQuXozN9g= 8F9-cY2C0fuSAFvZhMURLO2QoS5yRjeqepzz3Hfciyj6UN4$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!8eEFGH4vyGJNUkN5THSby62KPT7I_FgxPS2lQuXozN9g= 8F9-cY2C0fuSAFvZhMURLO2QoS5yRjeqepzz3Hfcyd193Nw$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!8eEFGH4vyGJNUkN5THSby62KPT7I_FgxPS2lQuXozN9g= 8F9-cY2C0fuSAFvZhMURLO2QoS5yRjeqepzz3HfcMZN_d4Y$=20

=3D =3D =3D
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FOUS30 KWBC 290055
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
855 PM EDT Sat Jun 28 2025

Day 1
Valid 01Z Sun Jun 29 2025 - 12Z Sun Jun 29 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS OF SOUTH-CENTRAL MISSOURI AND NORTH-CENTRAL ARKANSAS...

01Z Update...
Maintained outlooks in all four areas, with some adjustments based
on radar trends and recent hi-res guidance. The biggest adjustment
was to expand the Marginal Risk area over the southern High Plains
farther west to include ongoing convection along the southeastern=20 NM/northwestern TX border. Otherwise, made only minor adjustments=20
to the previous outlook areas, including the Slight Risk centered=20
over southern Missouri and northern Arkansas.

Pereira


Previous Discussion...

...Middle/Lower Mississippi Valley and adjacent southern
Plains, Ohio and Tennessee valleys...

Firmly in the warm sector and within a moist airmass containing
widespread PWATs of 1.8-2.2" (near the 90th climatological
percentile), isolated to scattered flash flooding is possible
today with a potentially higher focus across parts of southern MO
and northern AR tonight, where a Slight Risk of Excessive Rainfall
was introduced in the 16z update. An MCV evident on morning radar
and satellite imagery has already prompted a few FFWs across
eastern OK and KS while gradually pushing eastward. This feature
will aid in sparking widely scattered slow- moving thunderstorms
throughout the afternoon while instability levels rise due to
diurnal heating. Pulse thunderstorms within weak steering flow and
an unstable/moist environment are also likely through much of the
Ohio and Tennessee valleys today, with smaller scale scattered
flash flooding possible. Current trends are for the aforementioned
MCV to make it into the vicinity of southeast MO by late tonight
and influence a sharp mid-level trough ahead of increasing warm air
advection throughout the Plains due to a crossing shortwave in the
north- central U.S. and the nighttime low- level jet. CAMs still
differ somewhat in the exact location of a potential northwest-
southeast oriented band of slow-moving storms, but generally
converge on south-central MO and don't really develop until around
09z tonight. The 12z HREF has increased 24-hr probs (12z Sat-12z
Sun) for greater than 5" of rain to 30-45% within the Slight Risk
outline. Additionally, this part of the country also has relatively
saturated soils already (70-100% 0-40 cm below ground relative
soil moisture percentiles per NASA SPoRT) not including the
likelihood of scattered thunderstorms and potentially overlapping
heavy rainfall this afternoon.

...Northern Plains and Upper Midwest...

Showers and thunderstorms capable of producing locally heavy
rainfall rates and heavy rainfall totals have the potential to
produce flash flooding as the next upper shortwave trough
approaches the north-central United States. Aided by a 90kt upper
level jet streak on the lee side...the upper trough will generate a
compact area of fairly robust, transient deep-layer forcing over
the outlook area later today and tonight. MUCAPEs are expected to
soar within the warm sector prior to the surface cold frontal
passage late tonight. Given precipitable water values getting near
1.75 inches...storms which form within the unstable airmass will
be capable of producing rainfall rates in excess 1.5"/hr and areal
average rainfall amounts of 1 to 3 inches...especially once low-
level inflow accelerates to between 30 kts and 40kts at 850 mb
ahead of the approaching front. The storm/mesoscale nature of the
threat leads to uncertainty of a more focused corridor of higher
risk, but a Slight Risk was considered in central MN where forward
propagation of storms may begin slow this evening and is reinforced
by the highest 12z HREF probs (20-30%) for exceeding 3" in 6 hours.

...Central Appalachians to the Northeast...

There continues to be a concern for heavy to potentially excessive
rainfall to develop across western Pennsylvania and surrounding
areas as the frontal boundary sags southward and taps into the
pooled PW values of 1.5-2". 12z CAMs are not a robust with rainfall
amounts in the central Appalachians and keep things moving along in
the Northeast to limit any flash flooding to isolated instances.
However, the environment remains unstable and moist, so any slow-
moving storms could lead to forming mesoscale boundaries that
create locally intense rainfall. Farther north, the Marginal Risk
was removed across northern New England given unimpressive radar
trends this morning and a more progressive patter. Still, 1-1.5" of
rainfall could lead to very isolated and more nuisance flooding.

...Southeast and central Florida Peninsula...

Scattered pulse thunderstorms are expected across a broad warm
sector and near an upper trough lingering over the region as
seasonable instability develops with daytime heating. A greater
focus for intense rainfall also overlaps with higher FFG across
the central Gulf Coast and Florida Peninsula, where rainfall rates
of 2-3"/hr are possible but should weaken quickly before
convection is driven off outflow from numerous other pop-up storms.

...New Mexico...

Yet another day of thunderstorms is expected across portions of
southern New Mexico and west Texas with locally heavy rainfall
(1-2") possible. QPF trends (coverage, intensity) are more isolated
compared prior days with the moist south to southeast low-level
upslope flow likely resulting in more localized areas of heavier
rainfall focused across the Sacramento and Guadalupe Mtns south
through the Trans-Pecos. The flash flood potential is expected to
remain isolated.

Snell

Day 2
Valid 12Z Sun Jun 29 2025 - 12Z Mon Jun 30 2025

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL EXTENDING FROM
PORTIONS OF THE CENTRAL UNITED STATES TO THE CENTRAL GULF COAST AND MID-ATLANTIC...

Late-June weather pattern remains in place on Sunday with widely
scattered showers/storms and isolated chances for flash flooding
within the warm and humid airmass spanning from the central U.S. to
the Southeast and Mid-Atlantic. Showers and thunderstorms are
expected both along and well- ahead of a cold front sinking
southeastward across the central Plains and Midwest, as well as
associated with diurnal monsoon activity across the southern
Rockies and adjacent High Plains. At the start of day 2, there's
the potential for ongoing late-night convection across south-
central MO as a remnant MCV and overnight low-level jet foster
slow-moving thunderstorms. There remains rather high uncertainty
regarding the maintenance of thunderstorm activity in this region
past the 12z Sun start time of Day 2, but should greater certainty
arise a Slight Risk may be needed for south-central MO and nearby
regions.

Meanwhile, organized convection firing along the advancing cold
front across the central Plains and Midwest should provide another
focus for potential slow-moving convection in the evening before
activity should become more progressive under the influence of a
strengthening cold pool and progressive cold front. PWs approaching
2" and near the 90th climatological percentile will provide the
opportunity for intense rainfall rates scattered 2-4" rainfall
totals between parts of KS, MO, and southern IA.

Elsewhere within the warm sector across the Mid-South, Mid-
Atlantic, Southeast, and Southern Rockies/High Plains, typical
summer thunderstorms exhibiting scattered and a pulse mode are
likely. These storms may contain briefly very intense rainfall
rates, but see updrafts collapse quickly and become outflow
dependent. Where convective clusters merge or linger near a
stationary front draped across the Mid-Atlantic and central
Appalachians, isolated flash flooding is possible.

Snell/Bann

Day 3
Valid 12Z Mon Jun 30 2025 - 12Z Tue Jul 01 2025

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS
OF THE SOUTHERN ROCKIES EASTWARD INTO THE MID ATLANTIC...

Similar to Sunday...convection is expected to develop within a region
of decent CAPE and precipitable water values in excess of 2
standard deviations above climatology. Except for some mid-level
westerly flow around the Great Lakes to provide some shear
there...the flow farther south should be fairly meager (but offset
by steeper low-level lapse rates). This sets up the potential for
some local rainfall rates in excess of 1 inch per hour that results
in excessive rainfall from the Southern Rockies/Western High
Plains east/northeastward into the Ohio Valley and parts of the
Mid- Atlantic region on Monday and Monday night. A weakening
surface boundary will help focus some of the threat for heavier
rainfall but its placement is quite uncertain. One area at the
moment that is being monitored for a potential upgrade to a Slight
Risk are parts of the Upper Ohio Valley and central Appalachians
(centered over western PA). The synoptic setup with a
stationary/warm front stretching across southern PA and an
approaching cold front from the west should help foster greater
coverage in showers/storms within a moist environment, but storm
motions within a mean column wind of 30kts could limit the
flooding threat even though this area remains sensitive to intense
rainfall. Therefor, a Marginal Risk was maintained to highlight the
threat for isolated flash flooding.

Snell/Bann


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!6rVdy-6W-xktBWpXVjcEkb6w7MY18pmUsV9iNWwLmfm-= iGIz3bBj2d8UMPdR8XEQwXlHrZbXr4RwDDYRwV39UUPaHyU$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!6rVdy-6W-xktBWpXVjcEkb6w7MY18pmUsV9iNWwLmfm-= iGIz3bBj2d8UMPdR8XEQwXlHrZbXr4RwDDYRwV3986YkJTY$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!6rVdy-6W-xktBWpXVjcEkb6w7MY18pmUsV9iNWwLmfm-= iGIz3bBj2d8UMPdR8XEQwXlHrZbXr4RwDDYRwV39qQuAX3Q$=20

=3D =3D =3D
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FOUS30 KWBC 290057
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
857 PM EDT Sat Jun 28 2025

Day 1
Valid 01Z Sun Jun 29 2025 - 12Z Sun Jun 29 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS OF SOUTH-CENTRAL MISSOURI AND NORTH-CENTRAL ARKANSAS...

01Z Update...
Maintained outlooks in all four areas, with some adjustments based
on radar trends and recent hi-res guidance. The biggest adjustment
was to expand the Marginal Risk area over the southern High Plains
farther north and east to include ongoing convection along the=20
southeastern NM/northwestern TX border. Otherwise, made only minor=20 adjustments to the previous outlook areas, including the Slight=20
Risk centered over southern Missouri and northern Arkansas.

Pereira


Previous Discussion...

...Middle/Lower Mississippi Valley and adjacent southern
Plains, Ohio and Tennessee valleys...

Firmly in the warm sector and within a moist airmass containing
widespread PWATs of 1.8-2.2" (near the 90th climatological
percentile), isolated to scattered flash flooding is possible
today with a potentially higher focus across parts of southern MO
and northern AR tonight, where a Slight Risk of Excessive Rainfall
was introduced in the 16z update. An MCV evident on morning radar
and satellite imagery has already prompted a few FFWs across
eastern OK and KS while gradually pushing eastward. This feature
will aid in sparking widely scattered slow- moving thunderstorms
throughout the afternoon while instability levels rise due to
diurnal heating. Pulse thunderstorms within weak steering flow and
an unstable/moist environment are also likely through much of the
Ohio and Tennessee valleys today, with smaller scale scattered
flash flooding possible. Current trends are for the aforementioned
MCV to make it into the vicinity of southeast MO by late tonight
and influence a sharp mid-level trough ahead of increasing warm air
advection throughout the Plains due to a crossing shortwave in the
north- central U.S. and the nighttime low- level jet. CAMs still
differ somewhat in the exact location of a potential northwest-
southeast oriented band of slow-moving storms, but generally
converge on south-central MO and don't really develop until around
09z tonight. The 12z HREF has increased 24-hr probs (12z Sat-12z
Sun) for greater than 5" of rain to 30-45% within the Slight Risk
outline. Additionally, this part of the country also has relatively
saturated soils already (70-100% 0-40 cm below ground relative
soil moisture percentiles per NASA SPoRT) not including the
likelihood of scattered thunderstorms and potentially overlapping
heavy rainfall this afternoon.

...Northern Plains and Upper Midwest...

Showers and thunderstorms capable of producing locally heavy
rainfall rates and heavy rainfall totals have the potential to
produce flash flooding as the next upper shortwave trough
approaches the north-central United States. Aided by a 90kt upper
level jet streak on the lee side...the upper trough will generate a
compact area of fairly robust, transient deep-layer forcing over
the outlook area later today and tonight. MUCAPEs are expected to
soar within the warm sector prior to the surface cold frontal
passage late tonight. Given precipitable water values getting near
1.75 inches...storms which form within the unstable airmass will
be capable of producing rainfall rates in excess 1.5"/hr and areal
average rainfall amounts of 1 to 3 inches...especially once low-
level inflow accelerates to between 30 kts and 40kts at 850 mb
ahead of the approaching front. The storm/mesoscale nature of the
threat leads to uncertainty of a more focused corridor of higher
risk, but a Slight Risk was considered in central MN where forward
propagation of storms may begin slow this evening and is reinforced
by the highest 12z HREF probs (20-30%) for exceeding 3" in 6 hours.

...Central Appalachians to the Northeast...

There continues to be a concern for heavy to potentially excessive
rainfall to develop across western Pennsylvania and surrounding
areas as the frontal boundary sags southward and taps into the
pooled PW values of 1.5-2". 12z CAMs are not a robust with rainfall
amounts in the central Appalachians and keep things moving along in
the Northeast to limit any flash flooding to isolated instances.
However, the environment remains unstable and moist, so any slow-
moving storms could lead to forming mesoscale boundaries that
create locally intense rainfall. Farther north, the Marginal Risk
was removed across northern New England given unimpressive radar
trends this morning and a more progressive patter. Still, 1-1.5" of
rainfall could lead to very isolated and more nuisance flooding.

...Southeast and central Florida Peninsula...

Scattered pulse thunderstorms are expected across a broad warm
sector and near an upper trough lingering over the region as
seasonable instability develops with daytime heating. A greater
focus for intense rainfall also overlaps with higher FFG across
the central Gulf Coast and Florida Peninsula, where rainfall rates
of 2-3"/hr are possible but should weaken quickly before
convection is driven off outflow from numerous other pop-up storms.

...New Mexico...

Yet another day of thunderstorms is expected across portions of
southern New Mexico and west Texas with locally heavy rainfall
(1-2") possible. QPF trends (coverage, intensity) are more isolated
compared prior days with the moist south to southeast low-level
upslope flow likely resulting in more localized areas of heavier
rainfall focused across the Sacramento and Guadalupe Mtns south
through the Trans-Pecos. The flash flood potential is expected to
remain isolated.

Snell

Day 2
Valid 12Z Sun Jun 29 2025 - 12Z Mon Jun 30 2025

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL EXTENDING FROM
PORTIONS OF THE CENTRAL UNITED STATES TO THE CENTRAL GULF COAST AND MID-ATLANTIC...

Late-June weather pattern remains in place on Sunday with widely
scattered showers/storms and isolated chances for flash flooding
within the warm and humid airmass spanning from the central U.S. to
the Southeast and Mid-Atlantic. Showers and thunderstorms are
expected both along and well- ahead of a cold front sinking
southeastward across the central Plains and Midwest, as well as
associated with diurnal monsoon activity across the southern
Rockies and adjacent High Plains. At the start of day 2, there's
the potential for ongoing late-night convection across south-
central MO as a remnant MCV and overnight low-level jet foster
slow-moving thunderstorms. There remains rather high uncertainty
regarding the maintenance of thunderstorm activity in this region
past the 12z Sun start time of Day 2, but should greater certainty
arise a Slight Risk may be needed for south-central MO and nearby
regions.

Meanwhile, organized convection firing along the advancing cold
front across the central Plains and Midwest should provide another
focus for potential slow-moving convection in the evening before
activity should become more progressive under the influence of a
strengthening cold pool and progressive cold front. PWs approaching
2" and near the 90th climatological percentile will provide the
opportunity for intense rainfall rates scattered 2-4" rainfall
totals between parts of KS, MO, and southern IA.

Elsewhere within the warm sector across the Mid-South, Mid-
Atlantic, Southeast, and Southern Rockies/High Plains, typical
summer thunderstorms exhibiting scattered and a pulse mode are
likely. These storms may contain briefly very intense rainfall
rates, but see updrafts collapse quickly and become outflow
dependent. Where convective clusters merge or linger near a
stationary front draped across the Mid-Atlantic and central
Appalachians, isolated flash flooding is possible.

Snell/Bann

Day 3
Valid 12Z Mon Jun 30 2025 - 12Z Tue Jul 01 2025

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS
OF THE SOUTHERN ROCKIES EASTWARD INTO THE MID ATLANTIC...

Similar to Sunday...convection is expected to develop within a region
of decent CAPE and precipitable water values in excess of 2
standard deviations above climatology. Except for some mid-level
westerly flow around the Great Lakes to provide some shear
there...the flow farther south should be fairly meager (but offset
by steeper low-level lapse rates). This sets up the potential for
some local rainfall rates in excess of 1 inch per hour that results
in excessive rainfall from the Southern Rockies/Western High
Plains east/northeastward into the Ohio Valley and parts of the
Mid- Atlantic region on Monday and Monday night. A weakening
surface boundary will help focus some of the threat for heavier
rainfall but its placement is quite uncertain. One area at the
moment that is being monitored for a potential upgrade to a Slight
Risk are parts of the Upper Ohio Valley and central Appalachians
(centered over western PA). The synoptic setup with a
stationary/warm front stretching across southern PA and an
approaching cold front from the west should help foster greater
coverage in showers/storms within a moist environment, but storm
motions within a mean column wind of 30kts could limit the
flooding threat even though this area remains sensitive to intense
rainfall. Therefor, a Marginal Risk was maintained to highlight the
threat for isolated flash flooding.

Snell/Bann


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!5fRJnZGbqZXz089XkwUX3xh2w9sj0ibkTui6TPigQVMO= bOc-bThnRRVu4abg_sH-E5nH28SESsPucOXaZqavwx61b8A$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!5fRJnZGbqZXz089XkwUX3xh2w9sj0ibkTui6TPigQVMO= bOc-bThnRRVu4abg_sH-E5nH28SESsPucOXaZqavsc7zDis$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!5fRJnZGbqZXz089XkwUX3xh2w9sj0ibkTui6TPigQVMO= bOc-bThnRRVu4abg_sH-E5nH28SESsPucOXaZqavdK9PrNg$=20

=3D =3D =3D
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FOUS30 KWBC 290325
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
1125 PM EDT Sat Jun 28 2025

Day 1
Valid 0318Z Sun Jun 29 2025 - 12Z Mon Jun 30 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS OF SOUTH-CENTRAL MISSOURI/NORTH-CENTRAL ARKANSAS AS WELL AS PARTS OF
THE UPPER MIDWEST...

03Z Update...
Upgraded to a Slight Risk across portions of the Upper Midwest as
convection with intense rainfall rates has become increasingly
aligned with the 850 mb flow...leading to concerns about flash=20
flooding over portions of Minnesota into a small portion of far=20
southeast South Dakota for at least a few more hours. Furtber=20
details available in Mesoscale Precipitation 0546.

Bann


01Z Update...
Maintained outlooks in all four areas, with some adjustments based
on radar trends and recent hi-res guidance. The biggest adjustment
was to expand the Marginal Risk area over the southern High Plains
farther north and east to include ongoing convection along the
southeastern NM/northwestern TX border. Otherwise, made only minor
adjustments to the previous outlook areas, including the Slight
Risk centered over southern Missouri and northern Arkansas.

Pereira


Previous Discussion...

...Middle/Lower Mississippi Valley and adjacent southern
Plains, Ohio and Tennessee valleys...

Firmly in the warm sector and within a moist airmass containing
widespread PWATs of 1.8-2.2" (near the 90th climatological
percentile), isolated to scattered flash flooding is possible
today with a potentially higher focus across parts of southern MO
and northern AR tonight, where a Slight Risk of Excessive Rainfall
was introduced in the 16z update. An MCV evident on morning radar
and satellite imagery has already prompted a few FFWs across
eastern OK and KS while gradually pushing eastward. This feature
will aid in sparking widely scattered slow- moving thunderstorms
throughout the afternoon while instability levels rise due to
diurnal heating. Pulse thunderstorms within weak steering flow and
an unstable/moist environment are also likely through much of the
Ohio and Tennessee valleys today, with smaller scale scattered
flash flooding possible. Current trends are for the aforementioned
MCV to make it into the vicinity of southeast MO by late tonight
and influence a sharp mid-level trough ahead of increasing warm air
advection throughout the Plains due to a crossing shortwave in the
north- central U.S. and the nighttime low- level jet. CAMs still
differ somewhat in the exact location of a potential northwest-
southeast oriented band of slow-moving storms, but generally
converge on south-central MO and don't really develop until around
09z tonight. The 12z HREF has increased 24-hr probs (12z Sat-12z
Sun) for greater than 5" of rain to 30-45% within the Slight Risk
outline. Additionally, this part of the country also has relatively
saturated soils already (70-100% 0-40 cm below ground relative
soil moisture percentiles per NASA SPoRT) not including the
likelihood of scattered thunderstorms and potentially overlapping
heavy rainfall this afternoon.

...Northern Plains and Upper Midwest...

Showers and thunderstorms capable of producing locally heavy
rainfall rates and heavy rainfall totals have the potential to
produce flash flooding as the next upper shortwave trough
approaches the north-central United States. Aided by a 90kt upper
level jet streak on the lee side...the upper trough will generate a
compact area of fairly robust, transient deep-layer forcing over
the outlook area later today and tonight. MUCAPEs are expected to
soar within the warm sector prior to the surface cold frontal
passage late tonight. Given precipitable water values getting near
1.75 inches...storms which form within the unstable airmass will
be capable of producing rainfall rates in excess 1.5"/hr and areal
average rainfall amounts of 1 to 3 inches...especially once low-
level inflow accelerates to between 30 kts and 40kts at 850 mb
ahead of the approaching front. The storm/mesoscale nature of the
threat leads to uncertainty of a more focused corridor of higher
risk, but a Slight Risk was considered in central MN where forward
propagation of storms may begin slow this evening and is reinforced
by the highest 12z HREF probs (20-30%) for exceeding 3" in 6 hours.

...Central Appalachians to the Northeast...

There continues to be a concern for heavy to potentially excessive
rainfall to develop across western Pennsylvania and surrounding
areas as the frontal boundary sags southward and taps into the
pooled PW values of 1.5-2". 12z CAMs are not a robust with rainfall
amounts in the central Appalachians and keep things moving along in
the Northeast to limit any flash flooding to isolated instances.
However, the environment remains unstable and moist, so any slow-
moving storms could lead to forming mesoscale boundaries that
create locally intense rainfall. Farther north, the Marginal Risk
was removed across northern New England given unimpressive radar
trends this morning and a more progressive patter. Still, 1-1.5" of
rainfall could lead to very isolated and more nuisance flooding.

...Southeast and central Florida Peninsula...

Scattered pulse thunderstorms are expected across a broad warm
sector and near an upper trough lingering over the region as
seasonable instability develops with daytime heating. A greater
focus for intense rainfall also overlaps with higher FFG across
the central Gulf Coast and Florida Peninsula, where rainfall rates
of 2-3"/hr are possible but should weaken quickly before
convection is driven off outflow from numerous other pop-up storms.

...New Mexico...

Yet another day of thunderstorms is expected across portions of
southern New Mexico and west Texas with locally heavy rainfall
(1-2") possible. QPF trends (coverage, intensity) are more isolated
compared prior days with the moist south to southeast low-level
upslope flow likely resulting in more localized areas of heavier
rainfall focused across the Sacramento and Guadalupe Mtns south
through the Trans-Pecos. The flash flood potential is expected to
remain isolated.

Snell

Day 2
Valid 12Z Mon Jun 30 2025 - 12Z Tue Jul 01 2025

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL EXTENDING FROM
PORTIONS OF THE CENTRAL UNITED STATES TO THE CENTRAL GULF COAST AND MID-ATLANTIC...

Late-June weather pattern remains in place on Sunday with widely
scattered showers/storms and isolated chances for flash flooding
within the warm and humid airmass spanning from the central U.S. to
the Southeast and Mid-Atlantic. Showers and thunderstorms are
expected both along and well- ahead of a cold front sinking
southeastward across the central Plains and Midwest, as well as
associated with diurnal monsoon activity across the southern
Rockies and adjacent High Plains. At the start of day 2, there's
the potential for ongoing late-night convection across south-
central MO as a remnant MCV and overnight low-level jet foster
slow-moving thunderstorms. There remains rather high uncertainty
regarding the maintenance of thunderstorm activity in this region
past the 12z Sun start time of Day 2, but should greater certainty
arise a Slight Risk may be needed for south-central MO and nearby
regions.

Meanwhile, organized convection firing along the advancing cold
front across the central Plains and Midwest should provide another
focus for potential slow-moving convection in the evening before
activity should become more progressive under the influence of a
strengthening cold pool and progressive cold front. PWs approaching
2" and near the 90th climatological percentile will provide the
opportunity for intense rainfall rates scattered 2-4" rainfall
totals between parts of KS, MO, and southern IA.

Elsewhere within the warm sector across the Mid-South, Mid-
Atlantic, Southeast, and Southern Rockies/High Plains, typical
summer thunderstorms exhibiting scattered and a pulse mode are
likely. These storms may contain briefly very intense rainfall
rates, but see updrafts collapse quickly and become outflow
dependent. Where convective clusters merge or linger near a
stationary front draped across the Mid-Atlantic and central
Appalachians, isolated flash flooding is possible.

Snell/Bann

Day 3
Valid 12Z Tue Jul 01 2025 - 12Z Wed Jul 02 2025

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS
OF THE SOUTHERN ROCKIES EASTWARD INTO THE MID ATLANTIC...

Similar to Sunday...convection is expected to develop within a region
of decent CAPE and precipitable water values in excess of 2
standard deviations above climatology. Except for some mid-level
westerly flow around the Great Lakes to provide some shear
there...the flow farther south should be fairly meager (but offset
by steeper low-level lapse rates). This sets up the potential for
some local rainfall rates in excess of 1 inch per hour that results
in excessive rainfall from the Southern Rockies/Western High
Plains east/northeastward into the Ohio Valley and parts of the
Mid- Atlantic region on Monday and Monday night. A weakening
surface boundary will help focus some of the threat for heavier
rainfall but its placement is quite uncertain. One area at the
moment that is being monitored for a potential upgrade to a Slight
Risk are parts of the Upper Ohio Valley and central Appalachians
(centered over western PA). The synoptic setup with a
stationary/warm front stretching across southern PA and an
approaching cold front from the west should help foster greater
coverage in showers/storms within a moist environment, but storm
motions within a mean column wind of 30kts could limit the
flooding threat even though this area remains sensitive to intense
rainfall. Therefor, a Marginal Risk was maintained to highlight the
threat for isolated flash flooding.

Snell/Bann


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!8PxS2HNv2QfJgvXCkZlCj1md0C09MALh2JpyucUS-FIw= eyYW_sravnpNIQeqY17f2USypwbk-f33iL4I4_MUNHLNbFs$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!8PxS2HNv2QfJgvXCkZlCj1md0C09MALh2JpyucUS-FIw= eyYW_sravnpNIQeqY17f2USypwbk-f33iL4I4_MUmS0qCMo$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!8PxS2HNv2QfJgvXCkZlCj1md0C09MALh2JpyucUS-FIw= eyYW_sravnpNIQeqY17f2USypwbk-f33iL4I4_MUGgamQwY$=20

=3D =3D =3D
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FOUS30 KWBC 290828
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
428 AM EDT Sun Jun 29 2025

Day 1
Valid 12Z Sun Jun 29 2025 - 12Z Mon Jun 30 2025

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL EXTENDING FROM=20
PORTIONS OF THE CENTRAL UNITED STATES TO THE CENTRAL GULF COAST AND MID-ATLANTIC...

Late-June weather pattern remains in place on Sunday with widely
scattered showers/storms and isolated chances for flash flooding
within the warm and humid airmass spanning from the central U.S. to
the Southeast and Mid-Atlantic. Showers and thunderstorms are
expected both along and well- ahead of a cold front sinking
southeastward across the central Plains and Midwest, as well as
associated with diurnal monsoon activity across the southern
Rockies and adjacent High Plains.=20

As Day 1 begins, late-night convection lingering across parts of=20
Missouri should be about to fade with the weakening of a low level=20
jet. With models showing renewed convection later today and tonight
across western Missouri/eastern Kansas that extends northward into
portions if Iowa...did introduce a Slight Risk area to the=20
outlook where organized convection from overnight approached the=20
area from the north. Precipitable water values approaching 2" and=20
near the 90th climatological percentile will provide the=20
opportunity for intense rainfall rates scattered 2-4" rainfall=20
totals between parts of KS, MO, and southern IA.

Elsewhere within the warm sector across the Mid-South, Mid-
Atlantic, Southeast, and Southern Rockies/High Plains, typical
summer thunderstorms exhibiting scattered and a pulse mode are
likely. These storms may contain briefly very intense rainfall
rates, but see updrafts collapse quickly and become outflow
dependent. Where convective clusters merge or linger near a
stationary front draped across the Mid-Atlantic and central
Appalachians, isolated flash flooding is possible.

Bann/Snell


Day 2
Valid 12Z Mon Jun 30 2025 - 12Z Tue Jul 01 2025

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS=20
OF THE SOUTHERN ROCKIES EASTWARD INTO THE MID ATLANTIC...

Similar to today...convection is expected to develop within a=20
region of decent CAPE and precipitable water values in excess of 2=20
standard deviations above climatology. Except for some mid-level=20
westerly flow around the Great Lakes to provide some shear=20
there...the flow farther south should be fairly meager (but offset=20
by steeper low-level lapse rates). This sets up the potential for=20
some local rainfall rates in excess of 1 inch per hour that results
in excessive rainfall from the Southern Rockies/Western High=20
Plains east/northeastward into the Ohio Valley and parts of the=20
Mid-Atlantic region on Monday and Monday night.=20

A weakening surface boundary will help focus some of the threat=20
for heavier rainfall but its placement remains quite uncertain.=20
One area that is still being monitored for a potential upgrade to a
Slight Risk are parts of the Upper Ohio Valley and central=20
Appalachians (centered over western PA). The synoptic setup with a=20 stationary/warm front stretching across southern PA and an=20
approaching cold front from the west should help foster greater=20
coverage in showers/storms within a moist environment, but storm=20
motions within a mean column wind of 30kts could limit the flooding
threat even though this area remains sensitive to intense=20
rainfall. Therefore, a Marginal Risk was maintained to highlight=20
the threat for isolated flash flooding.

Snell/Bann

Day 3=20
Valid 12Z Tue Jul 01 2025 - 12Z Wed Jul 02 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL OVER A PORTION OF
THE MID ATLANTIC...

The boundary that helps focus some of the threat for heavy to
potentially excessive rainfall on Day 2 will continue to shift=20
eastward and provide the focus for another round on Day 3.
The flow aloft becomes more supportive over the Northeast US as=20
divergence aloft increases in response to a digging trough aloft=20
and low level convergence increases along the boundary. Portions=20
of the Mid-Atlatic have suppressed Flash Flood Guidance from a=20
period of above normal rainfall making that area a bit more
susceptible to excessive rainfall...while faster cell motions
should preclude more than isolated instances of flash flooding
across the Northeast US.

Farther south/west along the boundary...convection is expected to
be develop within a region of decent CAPE and precipitable water=20
values in excess of 2 standard deviations above climatology. With
weaker flow aloft...locally heavy rainfall totals could result in
isolated instances of excessive rainfall.=20

Bann


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!5Z4WwZjNFsQ92uhxLAlvBmpjrq68qQXIJyB-1ilV77Ry= gJOWrtZSCpYvkXTFlj7sA_NPX8viLO7NWgSoWEfc1IOI7wM$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!5Z4WwZjNFsQ92uhxLAlvBmpjrq68qQXIJyB-1ilV77Ry= gJOWrtZSCpYvkXTFlj7sA_NPX8viLO7NWgSoWEfcpV8So14$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!5Z4WwZjNFsQ92uhxLAlvBmpjrq68qQXIJyB-1ilV77Ry= gJOWrtZSCpYvkXTFlj7sA_NPX8viLO7NWgSoWEfcAbzbCRQ$=20

=3D =3D =3D
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FOUS30 KWBC 291557
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
1157 AM EDT Sun Jun 29 2025

Day 1
Valid 16Z Sun Jun 29 2025 - 12Z Mon Jun 30 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PARTS OF THE
CENTRAL PLAINS AND MIDDLE MISSISSIPPI VALLEY...

Late-June weather pattern remains in place with widely scattered=20 showers/storms and isolated chances for flash flooding within the=20
warm and humid airmass spanning from the central U.S. to the=20
Southeast and Mid-Atlantic. Showers and thunderstorms are expected=20
both along and well- ahead of a cold front sinking southeastward=20
across the central Plains and Midwest, a stationary boundary
extending from the Mid-Atlantic to the Great Lakes, as well as=20
associated with diurnal monsoon activity across the southern=20
Rockies and adjacent High Plains.

Current radar and satellite imagery shows continued thunderstorm=20
activity from overnight across the eastern central Plains and into=20
the Mid-Mississippi Valley, producing mostly isolated flooding
concerns and Flash Flood Warnings ongoing across central MO. With=20
models showing renewed convection later today and tonight across=20
western Missouri/eastern Kansas that extends northward into=20
portions if Iowa...the Slight Risk was maintained. This renewed
convection is forecast to be driven by a sinking cold front and
diving upper trough over the north-central U.S.. Precipitable=20
water values approaching 2" and near the 90th climatological=20
percentile will provide the opportunity for intense rainfall rates=20
scattered 2-4" rainfall totals between parts of KS, MO, southern NE
and southern IA. However, given this event is within 12 hours=20
there remains rather large uncertainty within CAMs on convective=20
initiation and some may be picking up on morning convection laying=20
an outflow boundary farther south and limiting northward=20
development this evening across NE and southern IA or potentially=20
delaying it until late tonight. Either way, where heavy rain does=20
overlap with recently saturated soils, scattered flash flooding is=20
possible.

Elsewhere within the warm sector across the Mid-South, Mid-
Atlantic, Southeast, and Southern Rockies/High Plains, typical
summer thunderstorms exhibiting scattered and a pulse mode are
likely. These storms may contain briefly very intense rainfall
rates, but see updrafts collapse quickly and become outflow
dependent. Where convective clusters merge or linger near a
stationary front draped across the Mid-Atlantic and sensitive
terrain of the central Appalachians, isolated flash flooding is=20
possible. As always, should these intense and hard to pinpoint
tropical downpours occur over highly urbanized areas, flooding=20
impacts could become more impactful.

Snell


Day 2
Valid 12Z Mon Jun 30 2025 - 12Z Tue Jul 01 2025

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS
OF THE SOUTHERN ROCKIES EASTWARD INTO THE MID ATLANTIC...

Similar to today...convection is expected to develop within a
region of decent CAPE and precipitable water values in excess of 2
standard deviations above climatology. Except for some mid-level
westerly flow around the Great Lakes to provide some shear
there...the flow farther south should be fairly meager (but offset
by steeper low-level lapse rates). This sets up the potential for
some local rainfall rates in excess of 1 inch per hour that results
in excessive rainfall from the Southern Rockies/Western High
Plains east/northeastward into the Ohio Valley and parts of the
Mid-Atlantic region on Monday and Monday night.

A weakening surface boundary will help focus some of the threat
for heavier rainfall but its placement remains quite uncertain.
One area that is still being monitored for a potential upgrade to a
Slight Risk are parts of the Upper Ohio Valley and central
Appalachians (centered over western PA). The synoptic setup with a stationary/warm front stretching across southern PA and an
approaching cold front from the west should help foster greater
coverage in showers/storms within a moist environment, but storm
motions within a mean column wind of 30kts could limit the flooding
threat even though this area remains sensitive to intense
rainfall. Therefore, a Marginal Risk was maintained to highlight
the threat for isolated flash flooding.

Snell/Bann

Day 3
Valid 12Z Tue Jul 01 2025 - 12Z Wed Jul 02 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL OVER A PORTION OF
THE MID ATLANTIC...

The boundary that helps focus some of the threat for heavy to
potentially excessive rainfall on Day 2 will continue to shift
eastward and provide the focus for another round on Day 3.
The flow aloft becomes more supportive over the Northeast US as
divergence aloft increases in response to a digging trough aloft
and low level convergence increases along the boundary. Portions
of the Mid-Atlatic have suppressed Flash Flood Guidance from a
period of above normal rainfall making that area a bit more
susceptible to excessive rainfall...while faster cell motions
should preclude more than isolated instances of flash flooding
across the Northeast US.

Farther south/west along the boundary...convection is expected to
be develop within a region of decent CAPE and precipitable water
values in excess of 2 standard deviations above climatology. With
weaker flow aloft...locally heavy rainfall totals could result in
isolated instances of excessive rainfall.

Bann


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!93zQtcefSzZlAm6h0PmvCoS9QyW7oxPhP1LshVc27F9n= RQSHrrFp4LglBXeNjBxsg3N22EZEXHlw9f4fC0sjZxty7yY$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!93zQtcefSzZlAm6h0PmvCoS9QyW7oxPhP1LshVc27F9n= RQSHrrFp4LglBXeNjBxsg3N22EZEXHlw9f4fC0sjg3QxAGs$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!93zQtcefSzZlAm6h0PmvCoS9QyW7oxPhP1LshVc27F9n= RQSHrrFp4LglBXeNjBxsg3N22EZEXHlw9f4fC0sj4ciFCoY$=20

=3D =3D =3D
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FOUS30 KWBC 291942
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
342 PM EDT Sun Jun 29 2025

Day 1
Valid 16Z Sun Jun 29 2025 - 12Z Mon Jun 30 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PARTS OF THE
CENTRAL PLAINS AND MIDDLE MISSISSIPPI VALLEY...

Late-June weather pattern remains in place with widely scattered
showers/storms and isolated chances for flash flooding within the
warm and humid airmass spanning from the central U.S. to the
Southeast and Mid-Atlantic. Showers and thunderstorms are expected
both along and well- ahead of a cold front sinking southeastward
across the central Plains and Midwest, a stationary boundary
extending from the Mid-Atlantic to the Great Lakes, as well as
associated with diurnal monsoon activity across the southern
Rockies and adjacent High Plains.

Current radar and satellite imagery shows continued thunderstorm
activity from overnight across the eastern central Plains and into
the Mid-Mississippi Valley, producing mostly isolated flooding
concerns and Flash Flood Warnings ongoing across central MO. With
models showing renewed convection later today and tonight across
western Missouri/eastern Kansas that extends northward into
portions if Iowa...the Slight Risk was maintained. This renewed
convection is forecast to be driven by a sinking cold front and
diving upper trough over the north-central U.S.. Precipitable
water values approaching 2" and near the 90th climatological
percentile will provide the opportunity for intense rainfall rates
scattered 2-4" rainfall totals between parts of KS, MO, southern NE
and southern IA. However, given this event is within 12 hours
there remains rather large uncertainty within CAMs on convective
initiation and some may be picking up on morning convection laying
an outflow boundary farther south and limiting northward
development this evening across NE and southern IA or potentially
delaying it until late tonight. Either way, where heavy rain does
overlap with recently saturated soils, scattered flash flooding is
possible.

Elsewhere within the warm sector across the Mid-South, Mid-
Atlantic, Southeast, and Southern Rockies/High Plains, typical
summer thunderstorms exhibiting scattered and a pulse mode are
likely. These storms may contain briefly very intense rainfall
rates, but see updrafts collapse quickly and become outflow
dependent. Where convective clusters merge or linger near a
stationary front draped across the Mid-Atlantic and sensitive
terrain of the central Appalachians, isolated flash flooding is
possible. As always, should these intense and hard to pinpoint
tropical downpours occur over highly urbanized areas, flooding
impacts could become more impactful.

Snell


Day 2
Valid 12Z Mon Jun 30 2025 - 12Z Tue Jul 01 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS OF
NEW MEXICO AND WESTERN TEXAS...

A Slight Risk was introduced across New Mexico and into western
Texas with today's update. The driving factor behind the scattered
flash flood threat will be a frontal boundary dropping south into
the southern Plains and southern Rockies. This front will supply=20
moist easterly flow into the complex terrain of the southern=20
Rockies and provide greater coverage of thunderstorms by the=20
afternoon due to diurnal heating, increasing lapse rates and
instability. PWs of 1-1.5" are forecast and will near the 90th
climatological percentile and support rainfall rates of 1-2"/hr.
Additionally, widespread thunderstorm activity is also expected
into the southern High Plains along the associated frontal boundary
within an area of very weak mid-level flow. Storms will likely be
slow-moving across western Texas and eastern New Mexico before
becoming outflow dependent unless a large enough cold pool can
organize a larger thunderstorm complex.

Elsewhere, similar to today...convection is expected to develop=20
within a region of decent CAPE and precipitable water values in=20
excess of 2 standard deviations above climatology. Except for some=20
mid-level westerly flow around the Great Lakes to provide some=20
shear there...the flow farther south should be fairly meager (but=20
offset by steeper low-level lapse rates). This sets up the=20
potential for some local rainfall rates in excess of 1 inch per=20
hour that results in excessive rainfall from the southern Plains=20 east/northeastward into the Ohio Valley and parts of the Mid-=20
Atlantic region on Monday and Monday night. Some details are coming
into focus, which includes the likelihood of overnight convection
lingering into early Monday morning across parts of the central
Plains and Mid-Mississippi Valley. This activity led to an
expansion of the previous Marginal Risk northward. Meanwhile, an
upper trough lingering across the Southeast will continue to foster
an area of convergence on the southern/southwestern periphery,
which could lead to locally heavy rainfall along the eastern Gulf
Coast and much of the northern Florida Gulf Coast. There is some
potential for extremely heavy rainfall within this tropical airmass
and PWs of 2.25-2.5", but there's the potential for most rainfall
to occur over the Gulf waters at this time.=20

Farther north into the Ohio Valley, Appalachians and Northeast, a=20
weakening surface boundary will help focus some of the threat for=20
heavier rainfall with its placement remaining quite uncertain. One
area that is still being monitored for a potential upgrade to a=20
Slight Risk are parts of the Upper Ohio Valley and central=20
Appalachians (centered over western PA). The synoptic setup with a=20 stationary/warm front stretching across southern PA and an=20
approaching cold front from the west should help foster greater=20
coverage in showers/storms within a moist environment, but storm=20
motions within a mean column wind of 30kts could limit the flooding
threat even though this area remains sensitive to intense=20
rainfall. Therefore, a Marginal Risk was maintained to highlight=20
the threat for isolated flash flooding.

Snell/Bann

Day 3
Valid 12Z Tue Jul 01 2025 - 12Z Wed Jul 02 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL OVER A PORTION OF
THE MID ATLANTIC...

The boundary that helps focus some of the threat for heavy to
potentially excessive rainfall on Day 2 will continue to shift
eastward and provide the focus for another round on Day 3.
The flow aloft becomes more supportive over the Northeast US as
divergence aloft increases in response to a digging trough aloft
and low level convergence increases along the boundary. Portions
of the Mid-Atlatic have suppressed Flash Flood Guidance from a
period of above normal rainfall making that area a bit more
susceptible to excessive rainfall...while faster cell motions
should preclude more than isolated instances of flash flooding
across the Northeast US. The inherited Slight Risk was expanded
somewhat to the southwest in order to capture an area where mean
flow is briefly parallel to eventual line of thunderstorms before=20
the cold front kicks things eastward Tuesday night.

Farther south/west along the boundary...convection is expected to
be develop within a region of decent CAPE and precipitable water
values in excess of 2 standard deviations above climatology. With
weaker flow aloft...locally heavy rainfall totals could result in
isolated instances of excessive rainfall. A strong surge of
moisture is expected to push deeper into the Four Corners by
Tuesday in response to tropical moisture pushing northwestward
across Mexico and lifting to the east of a closed low churning near
the California coast. This could lead to greater thunderstorm
coverage across the Southwest/Four Corners on Tuesday and a broader
isolated flash flooding threat.

Snell/Bann


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!7lq9M-ss1dz9yUCUD7oIHe3RaomIZt5WjyFAILLCjE4h= VeS5yJeS_VRQvuEgN3RhXRmYNNt8I9N4sCOrgEIuQWOw6_w$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!7lq9M-ss1dz9yUCUD7oIHe3RaomIZt5WjyFAILLCjE4h= VeS5yJeS_VRQvuEgN3RhXRmYNNt8I9N4sCOrgEIunbp6Xo8$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!7lq9M-ss1dz9yUCUD7oIHe3RaomIZt5WjyFAILLCjE4h= VeS5yJeS_VRQvuEgN3RhXRmYNNt8I9N4sCOrgEIuHy-aM3I$=20

=3D =3D =3D
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FOUS30 KWBC 300055
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
855 PM EDT Sun Jun 29 2025

Day 1
Valid 01Z Mon Jun 30 2025 - 12Z Mon Jun 30 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PARTS OF THE
CENTRAL PLAINS AND MIDDLE MISSISSIPPI VALLEY...

01Z Update...
Adjustments made to the previous outlook areas were based largely
on current observations and radar trends. This included the Slight
Risk area over the central Plains, which was shifted a little
further south and pulled west back into portions of northeastern=20
Oklahoma and eastern Kansas. Radar shows convection developing=20
along the western flank of the outflow associated with convection=20
the developed earlier over Missouri. High instability and deep=20
moisture, supported by southerly flow into the boundary may support
a growing heavy rainfall threat that is not well advertised by the
guidance. This may become the greater heavy rainfall/flash flood=20
threat, at least in the near term, as guidance does not provide a=20
strong indication that convection developing over the High Plains=20
this evening will propagate east back into the same areas over=20
eastern Kansas and Missouri impacted earlier by heavy rainfall.=20

Pereira

Previous Discussion...
Late-June weather pattern remains in place=20
with widely scattered showers/storms and isolated chances for flash
flooding within the warm and humid airmass spanning from the=20
central U.S. to the Southeast and Mid-Atlantic. Showers and=20
thunderstorms are expected both along and well- ahead of a cold=20
front sinking southeastward across the central Plains and Midwest,=20
a stationary boundary extending from the Mid-Atlantic to the Great=20
Lakes, as well as associated with diurnal monsoon activity across=20
the southern Rockies and adjacent High Plains.

Current radar and satellite imagery shows continued thunderstorm
activity from overnight across the eastern central Plains and into
the Mid-Mississippi Valley, producing mostly isolated flooding
concerns and Flash Flood Warnings ongoing across central MO. With
models showing renewed convection later today and tonight across
western Missouri/eastern Kansas that extends northward into
portions if Iowa...the Slight Risk was maintained. This renewed
convection is forecast to be driven by a sinking cold front and
diving upper trough over the north-central U.S.. Precipitable
water values approaching 2" and near the 90th climatological
percentile will provide the opportunity for intense rainfall rates
scattered 2-4" rainfall totals between parts of KS, MO, southern NE
and southern IA. However, given this event is within 12 hours
there remains rather large uncertainty within CAMs on convective
initiation and some may be picking up on morning convection laying
an outflow boundary farther south and limiting northward
development this evening across NE and southern IA or potentially
delaying it until late tonight. Either way, where heavy rain does
overlap with recently saturated soils, scattered flash flooding is
possible.

Elsewhere within the warm sector across the Mid-South, Mid-
Atlantic, Southeast, and Southern Rockies/High Plains, typical
summer thunderstorms exhibiting scattered and a pulse mode are
likely. These storms may contain briefly very intense rainfall
rates, but see updrafts collapse quickly and become outflow
dependent. Where convective clusters merge or linger near a
stationary front draped across the Mid-Atlantic and sensitive
terrain of the central Appalachians, isolated flash flooding is
possible. As always, should these intense and hard to pinpoint
tropical downpours occur over highly urbanized areas, flooding
impacts could become more impactful.

Snell


Day 2
Valid 12Z Mon Jun 30 2025 - 12Z Tue Jul 01 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS OF
NEW MEXICO AND WESTERN TEXAS...

A Slight Risk was introduced across New Mexico and into western
Texas with today's update. The driving factor behind the scattered
flash flood threat will be a frontal boundary dropping south into
the southern Plains and southern Rockies. This front will supply
moist easterly flow into the complex terrain of the southern
Rockies and provide greater coverage of thunderstorms by the
afternoon due to diurnal heating, increasing lapse rates and
instability. PWs of 1-1.5" are forecast and will near the 90th
climatological percentile and support rainfall rates of 1-2"/hr.
Additionally, widespread thunderstorm activity is also expected
into the southern High Plains along the associated frontal boundary
within an area of very weak mid-level flow. Storms will likely be
slow-moving across western Texas and eastern New Mexico before
becoming outflow dependent unless a large enough cold pool can
organize a larger thunderstorm complex.

Elsewhere, similar to today...convection is expected to develop
within a region of decent CAPE and precipitable water values in
excess of 2 standard deviations above climatology. Except for some
mid-level westerly flow around the Great Lakes to provide some
shear there...the flow farther south should be fairly meager (but
offset by steeper low-level lapse rates). This sets up the
potential for some local rainfall rates in excess of 1 inch per
hour that results in excessive rainfall from the southern Plains east/northeastward into the Ohio Valley and parts of the Mid-
Atlantic region on Monday and Monday night. Some details are coming
into focus, which includes the likelihood of overnight convection
lingering into early Monday morning across parts of the central
Plains and Mid-Mississippi Valley. This activity led to an
expansion of the previous Marginal Risk northward. Meanwhile, an
upper trough lingering across the Southeast will continue to foster
an area of convergence on the southern/southwestern periphery,
which could lead to locally heavy rainfall along the eastern Gulf
Coast and much of the northern Florida Gulf Coast. There is some
potential for extremely heavy rainfall within this tropical airmass
and PWs of 2.25-2.5", but there's the potential for most rainfall
to occur over the Gulf waters at this time.

Farther north into the Ohio Valley, Appalachians and Northeast, a
weakening surface boundary will help focus some of the threat for
heavier rainfall with its placement remaining quite uncertain. One
area that is still being monitored for a potential upgrade to a
Slight Risk are parts of the Upper Ohio Valley and central
Appalachians (centered over western PA). The synoptic setup with a stationary/warm front stretching across southern PA and an
approaching cold front from the west should help foster greater
coverage in showers/storms within a moist environment, but storm
motions within a mean column wind of 30kts could limit the flooding
threat even though this area remains sensitive to intense
rainfall. Therefore, a Marginal Risk was maintained to highlight
the threat for isolated flash flooding.

Snell/Bann

Day 3
Valid 12Z Tue Jul 01 2025 - 12Z Wed Jul 02 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL OVER A PORTION OF
THE MID ATLANTIC...

The boundary that helps focus some of the threat for heavy to
potentially excessive rainfall on Day 2 will continue to shift
eastward and provide the focus for another round on Day 3.
The flow aloft becomes more supportive over the Northeast US as
divergence aloft increases in response to a digging trough aloft
and low level convergence increases along the boundary. Portions
of the Mid-Atlatic have suppressed Flash Flood Guidance from a
period of above normal rainfall making that area a bit more
susceptible to excessive rainfall...while faster cell motions
should preclude more than isolated instances of flash flooding
across the Northeast US. The inherited Slight Risk was expanded
somewhat to the southwest in order to capture an area where mean
flow is briefly parallel to eventual line of thunderstorms before
the cold front kicks things eastward Tuesday night.

Farther south/west along the boundary...convection is expected to
be develop within a region of decent CAPE and precipitable water
values in excess of 2 standard deviations above climatology. With
weaker flow aloft...locally heavy rainfall totals could result in
isolated instances of excessive rainfall. A strong surge of
moisture is expected to push deeper into the Four Corners by
Tuesday in response to tropical moisture pushing northwestward
across Mexico and lifting to the east of a closed low churning near
the California coast. This could lead to greater thunderstorm
coverage across the Southwest/Four Corners on Tuesday and a broader
isolated flash flooding threat.

Snell/Bann


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!4Vm2UTLVH0QWb4asaMLFVTD_aCFr5asKKzjwL7iEbMqV= vFfzr1Xe48biJEFu9AKMJJrhV80k75c-sbmukAeFFEPTkEY$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!4Vm2UTLVH0QWb4asaMLFVTD_aCFr5asKKzjwL7iEbMqV= vFfzr1Xe48biJEFu9AKMJJrhV80k75c-sbmukAeF_I6tBVs$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!4Vm2UTLVH0QWb4asaMLFVTD_aCFr5asKKzjwL7iEbMqV= vFfzr1Xe48biJEFu9AKMJJrhV80k75c-sbmukAeFCubTgEA$=20

=3D =3D =3D
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FOUS30 KWBC 300828
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
428 AM EDT Mon Jun 30 2025

Day 1
Valid 12Z Mon Jun 30 2025 - 12Z Tue Jul 01 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS OF
THE CENTRAL/SOUTHERN PLAINS AND THE NEW MEXICO AND WESTERN=20
TEXAS...

A Slight Risk was maintained across New Mexico and into western=20
Texas given the presence of a front dropping southward into the
Southern Plains and Southern Rockies...with moist easterly flow=20
into the complex terrain of the southern Rockies and provide=20
greater coverage of thunderstorms by the afternoon due to diurnal=20
heating, increasing lapse rates and instability. Precipitable water
values of 1 inch to 1.5 inches are forecast and will near the 90th climatological percentile and support rainfall rates of 1-2 inches
per hour. Additionally, widespread coverage of thunderstorm=20
activity over parts of the Central and High Plains overnight was
accounted for by the introduction of a Slight Risk mainly from
Kansas into Oklahoma this morning before another round of=20
convection forms over the Southern High Plains along the associated
frontal boundary within an area of very weak mid- level flow later
today. Storms will likely be slow- moving across western Texas and
eastern New Mexico before becoming outflow dependent unless a=20
large enough cold pool can organize a larger thunderstorm complex.

Elsewhere...convection is expected to develop within a region of=20
decent CAPE and precipitable water values in excess of 2 standard=20
deviations above climatology. Except for some mid-level westerly=20
flow around the Great Lakes to provide some shear there...the flow=20
farther south should be fairly meager (but offset by steeper low-=20
level lapse rates). This sets up the potential for some local=20
rainfall rates in excess of 1 inch per hour that results in=20
excessive rainfall from the southern Plains east/northeastward into
the Ohio Valley and parts of the Mid- Atlantic region today and
tonight.=20

Some details are coming into focus, which includes the=20
likelihood of overnight convection lingering into the early-morning
hours across parts of the central Plains and Mid- Mississippi=20
Valley. Meanwhile, an upper trough lingering across the Southeast=20
will continue to foster an area of convergence on the=20
southern/southwestern periphery which could lead to locally heavy=20
rainfall along the eastern Gulf Coast and much of the northern=20
Florida Gulf Coast. There is some potential for extremely heavy=20
rainfall within this tropical airmass and precipitable water values
between 2.25 inches and 2.5 inches, but the signal from the
numerical guidance is that most rainfall to occur over the Gulf=20
waters at this time.

Farther north into the Ohio Valley, Appalachians and Northeast, a
weakening surface boundary will help focus some of the threat for
heavier rainfall with its placement remaining quite uncertain. The
synoptic setup with a stationary/warm front stretching across=20
southern PA and an approaching cold front from the west should help
foster greater coverage in showers/storms within a moist=20
environment, but storm motions within a mean column wind of 30kts=20
could limit the flooding threat even though this area remains=20
sensitive to intense rainfall.=20

Snell/Bann

Day 2
Valid 12Z Tue Jul 01 2025 - 12Z Wed Jul 02 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL OVER A PORTION OF=20
THE MID ATLANTIC...

The boundary that helps focus some of the threat for heavy to
potentially excessive rainfall on Day 1 will continue to shift=20
eastward and provide the focus for another round on Day 2. The=20
flow aloft becomes more supportive over the Northeast US as=20
divergence aloft increases in response to a digging trough in the
upper level while convergence is focused at the low-levels=20=20
convergence increases along the boundary. Portions of the Mid-=20
Atlantic have suppressed Flash Flood Guidance from a period of=20
above normal rainfall making that area a bit more susceptible to=20
excessive rainfall...while faster cell motions should generally=20
preclude more than isolated instances of flash flooding across the=20
Northeast US. The inherited Slight Risk was nudged a bit to the=20
west of its placement in the previous outlook towards a region of=20
better overlap between the deterministic QPF and the lower flash=20
flood guidance. The surrounding Marginal Risk area was changed=20
little from the previous outlook.=20

Farther south/west along the boundary...convection is expected to
be develop within a region of decent CAPE and precipitable water
values in excess of 2 standard deviations above climatology. With
weaker flow aloft...locally heavy rainfall totals could result in
isolated instances of excessive rainfall. A stronger push of=20
moisture is expected into the Four Corners by Tuesday in response=20
to tropical moisture pushing northwestward across Mexico and=20
lifting to the east of a closed low churning near the California=20
coast. This could lead to greater thunderstorm coverage across the=20 Southwest/Four Corners on Tuesday and a broader isolated flash=20
flooding threat.

Bann/Snell


Day 3
Valid 12Z Wed Jul 02 2025 - 12Z Thu Jul 03 2025

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL OVER PORTIONS OF
THE SOUTHEAST US AND ACROSS PARTS OF THE SOUTHERN HIGH PLAINS AND
NEARBY SOUTHERN ROCKIES...

Eastern US...
Drier air sweeping in behind the cold front over the eastern United
States should lead to decreasing coverage of excessive rainfall
potential on Wednesday. Prior to frontal passage...precipitable
water values in excess of 1.75 inches will still be in place and
the atmosphere will be capable of supporting locally intense
rainfall rates. The coastal; portions of the Carolinas and Georgia
will be the last to see the risk taper off.

To the west...a Marginal Risk area was maintained over portions of
the Southern Rockies and adjacent High Plains as deeper moisture
lingers over the area and 850-700 mb flow continues to draw Gulf
moisture northward into West Texas on Wednesday with shortwave
energy embedded within the broad south to southeast flow.=20

Bann


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!6mBNvJzgd6OAae665N9vZsOWOjY5G-5cGBW3lAhd4efP= y2zehlQjciLIfP5AtKT1Ub8rWXV0Q8M6Vc4NdKAIjDi7ZEQ$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!6mBNvJzgd6OAae665N9vZsOWOjY5G-5cGBW3lAhd4efP= y2zehlQjciLIfP5AtKT1Ub8rWXV0Q8M6Vc4NdKAIIRSaTs8$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!6mBNvJzgd6OAae665N9vZsOWOjY5G-5cGBW3lAhd4efP= y2zehlQjciLIfP5AtKT1Ub8rWXV0Q8M6Vc4NdKAI8O6NFTk$=20

=3D =3D =3D
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FOUS30 KWBC 301559
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
1159 AM EDT Mon Jun 30 2025

Day 1
Valid 16Z Mon Jun 30 2025 - 12Z Tue Jul 01 2025

...16Z Update...

Main changes to the overnight forecast include the introduction of a
Slight Risk over portions of the eastern Ohio Valley, Central=20
Appalachians, and Upper Mid-Atlantic. 12Z sounding data across the=20
region highlights a very moist and unstable airmass (PWATS at or
above the daily max for PIT and IAD) in the vicinity of a slow=20
moving warm front. Showers and thunderstorms are forecast to expand
in coverage today with continued heating, which will be capable of
very efficient subhourly rainfall rates which could breach in=20
spite of generally progressive storm motions.=20

Otherwise, the Slight Risk was trimmed in the Central/Southern
Plains in the wake of an overnight MCS which has sent a strong cold
pool southward. The main area of concern will focus along this
boundary later today, over portions of Central Oklahoma and Eastern
Arkansas into the Red River.

Asherman

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS OF
THE CENTRAL/SOUTHERN PLAINS AND THE NEW MEXICO AND WESTERN
TEXAS...

A Slight Risk was maintained across New Mexico and into western
Texas given the presence of a front dropping southward into the
Southern Plains and Southern Rockies...with moist easterly flow
into the complex terrain of the southern Rockies and provide
greater coverage of thunderstorms by the afternoon due to diurnal
heating, increasing lapse rates and instability. Precipitable water
values of 1 inch to 1.5 inches are forecast and will near the 90th climatological percentile and support rainfall rates of 1-2 inches
per hour. Additionally, widespread coverage of thunderstorm
activity over parts of the Central and High Plains overnight was
accounted for by the introduction of a Slight Risk mainly from
Kansas into Oklahoma this morning before another round of
convection forms over the Southern High Plains along the associated
frontal boundary within an area of very weak mid- level flow later
today. Storms will likely be slow- moving across western Texas and
eastern New Mexico before becoming outflow dependent unless a
large enough cold pool can organize a larger thunderstorm complex.

Elsewhere...convection is expected to develop within a region of
decent CAPE and precipitable water values in excess of 2 standard
deviations above climatology. Except for some mid-level westerly
flow around the Great Lakes to provide some shear there...the flow
farther south should be fairly meager (but offset by steeper low-
level lapse rates). This sets up the potential for some local
rainfall rates in excess of 1 inch per hour that results in
excessive rainfall from the southern Plains east/northeastward into
the Ohio Valley and parts of the Mid- Atlantic region today and
tonight.

Some details are coming into focus, which includes the
likelihood of overnight convection lingering into the early-morning
hours across parts of the central Plains and Mid- Mississippi
Valley. Meanwhile, an upper trough lingering across the Southeast
will continue to foster an area of convergence on the
southern/southwestern periphery which could lead to locally heavy
rainfall along the eastern Gulf Coast and much of the northern
Florida Gulf Coast. There is some potential for extremely heavy
rainfall within this tropical airmass and precipitable water values
between 2.25 inches and 2.5 inches, but the signal from the
numerical guidance is that most rainfall to occur over the Gulf
waters at this time.

Farther north into the Ohio Valley, Appalachians and Northeast, a
weakening surface boundary will help focus some of the threat for
heavier rainfall with its placement remaining quite uncertain. The
synoptic setup with a stationary/warm front stretching across
southern PA and an approaching cold front from the west should help
foster greater coverage in showers/storms within a moist
environment, but storm motions within a mean column wind of 30kts
could limit the flooding threat even though this area remains
sensitive to intense rainfall.

Snell/Bann

Day 2
Valid 12Z Tue Jul 01 2025 - 12Z Wed Jul 02 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL OVER A PORTION OF
THE MID ATLANTIC...

The boundary that helps focus some of the threat for heavy to
potentially excessive rainfall on Day 1 will continue to shift
eastward and provide the focus for another round on Day 2. The
flow aloft becomes more supportive over the Northeast US as
divergence aloft increases in response to a digging trough in the
upper level while convergence is focused at the low-levels
convergence increases along the boundary. Portions of the Mid-
Atlantic have suppressed Flash Flood Guidance from a period of
above normal rainfall making that area a bit more susceptible to
excessive rainfall...while faster cell motions should generally
preclude more than isolated instances of flash flooding across the
Northeast US. The inherited Slight Risk was nudged a bit to the
west of its placement in the previous outlook towards a region of
better overlap between the deterministic QPF and the lower flash
flood guidance. The surrounding Marginal Risk area was changed
little from the previous outlook.

Farther south/west along the boundary...convection is expected to
be develop within a region of decent CAPE and precipitable water
values in excess of 2 standard deviations above climatology. With
weaker flow aloft...locally heavy rainfall totals could result in
isolated instances of excessive rainfall. A stronger push of
moisture is expected into the Four Corners by Tuesday in response
to tropical moisture pushing northwestward across Mexico and
lifting to the east of a closed low churning near the California
coast. This could lead to greater thunderstorm coverage across the Southwest/Four Corners on Tuesday and a broader isolated flash
flooding threat.

Bann/Snell


Day 3
Valid 12Z Wed Jul 02 2025 - 12Z Thu Jul 03 2025

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL OVER PORTIONS OF
THE SOUTHEAST US AND ACROSS PARTS OF THE SOUTHERN HIGH PLAINS AND
NEARBY SOUTHERN ROCKIES...

Eastern US...
Drier air sweeping in behind the cold front over the eastern United
States should lead to decreasing coverage of excessive rainfall
potential on Wednesday. Prior to frontal passage...precipitable
water values in excess of 1.75 inches will still be in place and
the atmosphere will be capable of supporting locally intense
rainfall rates. The coastal; portions of the Carolinas and Georgia
will be the last to see the risk taper off.

To the west...a Marginal Risk area was maintained over portions of
the Southern Rockies and adjacent High Plains as deeper moisture
lingers over the area and 850-700 mb flow continues to draw Gulf
moisture northward into West Texas on Wednesday with shortwave
energy embedded within the broad south to southeast flow.

Bann


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!7c2YBMevv2PplWKvEtiSQPE0lcZmGQ2Cb3FQIFqrkEFz= X1EMhJsrr0yVqq19CjatNpeR0-soh3yeAdKo-CFa4OOyhwI$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!7c2YBMevv2PplWKvEtiSQPE0lcZmGQ2Cb3FQIFqrkEFz= X1EMhJsrr0yVqq19CjatNpeR0-soh3yeAdKo-CFa37XVQ6A$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!7c2YBMevv2PplWKvEtiSQPE0lcZmGQ2Cb3FQIFqrkEFz= X1EMhJsrr0yVqq19CjatNpeR0-soh3yeAdKo-CFaTBYPYMo$=20

=3D =3D =3D
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FOUS30 KWBC 302027
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
427 PM EDT Mon Jun 30 2025

Day 1
Valid 16Z Mon Jun 30 2025 - 12Z Tue Jul 01 2025

...16Z Update...

Main changes to the overnight forecast include the introduction of a
Slight Risk over portions of the eastern Ohio Valley, Central
Appalachians, and Upper Mid-Atlantic. 12Z sounding data across the
region highlights a very moist and unstable airmass (PWATS at or
above the daily max for PIT and IAD) in the vicinity of a slow
moving warm front. Showers and thunderstorms are forecast to expand
in coverage today with continued heating, which will be capable of
very efficient subhourly rainfall rates which could breach flash
flood guidance in spite of generally progressive storm motions.

Otherwise, the Slight Risk was trimmed in the Central/Southern
Plains in the wake of an overnight MCS which has sent a strong cold
pool southward. The main area of concern will focus along this
boundary later today, over portions of Central Oklahoma and Eastern
Arkansas into the Red River.

Asherman

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS OF
THE CENTRAL/SOUTHERN PLAINS AND THE NEW MEXICO AND WESTERN
TEXAS...

A Slight Risk was maintained across New Mexico and into western
Texas given the presence of a front dropping southward into the
Southern Plains and Southern Rockies...with moist easterly flow
into the complex terrain of the southern Rockies and provide
greater coverage of thunderstorms by the afternoon due to diurnal
heating, increasing lapse rates and instability. Precipitable water
values of 1 inch to 1.5 inches are forecast and will near the 90th climatological percentile and support rainfall rates of 1-2 inches
per hour. Additionally, widespread coverage of thunderstorm
activity over parts of the Central and High Plains overnight was
accounted for by the introduction of a Slight Risk mainly from
Kansas into Oklahoma this morning before another round of
convection forms over the Southern High Plains along the associated
frontal boundary within an area of very weak mid- level flow later
today. Storms will likely be slow- moving across western Texas and
eastern New Mexico before becoming outflow dependent unless a
large enough cold pool can organize a larger thunderstorm complex.

Elsewhere...convection is expected to develop within a region of
decent CAPE and precipitable water values in excess of 2 standard
deviations above climatology. Except for some mid-level westerly
flow around the Great Lakes to provide some shear there...the flow
farther south should be fairly meager (but offset by steeper low-
level lapse rates). This sets up the potential for some local
rainfall rates in excess of 1 inch per hour that results in
excessive rainfall from the southern Plains east/northeastward into
the Ohio Valley and parts of the Mid- Atlantic region today and
tonight.

Some details are coming into focus, which includes the
likelihood of overnight convection lingering into the early-morning
hours across parts of the central Plains and Mid- Mississippi
Valley. Meanwhile, an upper trough lingering across the Southeast
will continue to foster an area of convergence on the
southern/southwestern periphery which could lead to locally heavy
rainfall along the eastern Gulf Coast and much of the northern
Florida Gulf Coast. There is some potential for extremely heavy
rainfall within this tropical airmass and precipitable water values
between 2.25 inches and 2.5 inches, but the signal from the
numerical guidance is that most rainfall to occur over the Gulf
waters at this time.

Farther north into the Ohio Valley, Appalachians and Northeast, a
weakening surface boundary will help focus some of the threat for
heavier rainfall with its placement remaining quite uncertain. The
synoptic setup with a stationary/warm front stretching across
southern PA and an approaching cold front from the west should help
foster greater coverage in showers/storms within a moist
environment, but storm motions within a mean column wind of 30kts
could limit the flooding threat even though this area remains
sensitive to intense rainfall.

Snell/Bann

Day 2
Valid 12Z Tue Jul 01 2025 - 12Z Wed Jul 02 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL OVER A PORTION OF
THE MID ATLANTIC AND NORTHEAST...

...2030Z Update...
The Slight Risk was expanded across the Mid-Atlantic and Northeast=20
ahead of the cold front. Thunderstorms across the region today are
expected to "prime" soils across the region, which are already well
above average according to NASA SPoRT 0-40 cm soil moisture
percentiles. By early tomorrow afternoon, slow moving cold front=20
and right entrance region ascent are forecast to drive widespread=20 thunderstorms within an airmass characterized by PWAT values in the
97-99th percentile per the NAEFS. While individual cell motions=20
will likely be progressive (15-30 kts), steering flow oriented=20
parallel to the forcing should favor periods of cell training and
repeating ahead of the cold front. Both the 12Z HREF and REFS
neighborhood probabilities highlight a high (60-90%) chance of 24
hour QPF exceeding three inches across the area, with embedded 30-40%
maxima of at least five inches noted. Considerable to locally
significant flash flooding is possible tomorrow within sensitive
urban areas along the I-95 corridor, and over complex terrain in
the Appalachians.=20=20

Asherman

...PREVIOUS DISCUSSION...

The boundary that helps focus some of the threat for heavy to
potentially excessive rainfall on Day 1 will continue to shift
eastward and provide the focus for another round on Day 2. The
flow aloft becomes more supportive over the Northeast US as
divergence aloft increases in response to a digging trough in the
upper level while convergence is focused at the low-levels
convergence increases along the boundary. Portions of the Mid-
Atlantic have suppressed Flash Flood Guidance from a period of
above normal rainfall making that area a bit more susceptible to
excessive rainfall...while faster cell motions should generally
preclude more than isolated instances of flash flooding across the
Northeast US. The inherited Slight Risk was nudged a bit to the
west of its placement in the previous outlook towards a region of
better overlap between the deterministic QPF and the lower flash
flood guidance. The surrounding Marginal Risk area was changed
little from the previous outlook.

Farther south/west along the boundary...convection is expected to
be develop within a region of decent CAPE and precipitable water
values in excess of 2 standard deviations above climatology. With
weaker flow aloft...locally heavy rainfall totals could result in
isolated instances of excessive rainfall. A stronger push of
moisture is expected into the Four Corners by Tuesday in response
to tropical moisture pushing northwestward across Mexico and
lifting to the east of a closed low churning near the California
coast. This could lead to greater thunderstorm coverage across the Southwest/Four Corners on Tuesday and a broader isolated flash
flooding threat.

Bann/Snell


Day 3
Valid 12Z Wed Jul 02 2025 - 12Z Thu Jul 03 2025

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL OVER PORTIONS OF
THE SOUTHEAST US AND ACROSS PARTS OF THE SOUTHERN HIGH PLAINS AND
NEARBY SOUTHERN ROCKIES...

...2030Z Update...
Generally minor adjustments made to the overnight forecast,
including an expansion of the Marginal Risk into parts of the Mid-
Atlantic. Lingering heavy rainfall potential will remain as the=20
front slowly presses southeastward, driving additional showers and thunderstorms with 90th percentile PWATs which could overlap with=20
heavy rainfall from days 1-2.

The Marginal was also expanded in the Southern Rockies based on the
uptick in QPF as an upper-trough approaches from the west, while
southeasterly flow ushers in 97th-99th percentile PWATs into the
region.=20

Asherman/Bann

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!755GBQgemqlhZOsVkv2kkOQobTByVhVjHEeBOVp0e30z= XzrRGq5xdvVoBxbyb4Bb7IOYr8z2aTO5Pf-SO9SM8CI4n3Y$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!755GBQgemqlhZOsVkv2kkOQobTByVhVjHEeBOVp0e30z= XzrRGq5xdvVoBxbyb4Bb7IOYr8z2aTO5Pf-SO9SMTJfLsRE$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!755GBQgemqlhZOsVkv2kkOQobTByVhVjHEeBOVp0e30z= XzrRGq5xdvVoBxbyb4Bb7IOYr8z2aTO5Pf-SO9SM69ODcL0$=20

=3D =3D =3D
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FOUS30 KWBC 010050
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
850 PM EDT Mon Jun 30 2025

Day 1
Valid 01Z Tue Jul 01 2025 - 12Z Tue Jul 01 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS OF
THE CENTRAL/SOUTHERN PLAINS AND THE NEW MEXICO AND WESTERN
TEXAS...

...01Z Update...
Biggest adjustment at 01Z was to shift the Slight Risk area=20
further south across the Southern Plains. Recent runs of the HRRR=20
and the 18Z HREF generally agree that convection will continue=20
along a southwest-northeast axis from the Permian Basin in western=20
Texas to the Ouachita Mountains in southeastern Oklahoma and=20
western Arkansas. Neighborhood probabilities from the 18Z HREF=20
indicate that localized amounts of 2-3 inches are likely along this
axis during the remainder of the evening and overnight. Further to
the north, the Marginal Risk was removed from the Central Plains.

Elsewhere, made mostly minor adjustments based on radar trends and
recent hi-res guidance.

Pereira

...16Z Update...
Main changes to the overnight forecast include the introduction of
a Slight Risk over portions of the eastern Ohio Valley, Central=20 Appalachians, and Upper Mid-Atlantic. 12Z sounding data across the=20
region highlights a very moist and unstable airmass (PWATS at or=20
above the daily max for PIT and IAD) in the vicinity of a slow=20
moving warm front. Showers and thunderstorms are forecast to expand
in coverage today with continued heating, which will be capable of
very efficient subhourly rainfall rates which could breach flash=20
flood guidance in spite of generally progressive storm motions.

Otherwise, the Slight Risk was trimmed in the Central/Southern
Plains in the wake of an overnight MCS which has sent a strong cold
pool southward. The main area of concern will focus along this
boundary later today, over portions of Central Oklahoma and Eastern
Arkansas into the Red River.

Asherman


Previous Discussion...
A Slight Risk was maintained across New Mexico and into western
Texas given the presence of a front dropping southward into the
Southern Plains and Southern Rockies...with moist easterly flow
into the complex terrain of the southern Rockies and provide
greater coverage of thunderstorms by the afternoon due to diurnal
heating, increasing lapse rates and instability. Precipitable water
values of 1 inch to 1.5 inches are forecast and will near the 90th climatological percentile and support rainfall rates of 1-2 inches
per hour. Additionally, widespread coverage of thunderstorm
activity over parts of the Central and High Plains overnight was
accounted for by the introduction of a Slight Risk mainly from
Kansas into Oklahoma this morning before another round of
convection forms over the Southern High Plains along the associated
frontal boundary within an area of very weak mid- level flow later
today. Storms will likely be slow- moving across western Texas and
eastern New Mexico before becoming outflow dependent unless a
large enough cold pool can organize a larger thunderstorm complex.

Elsewhere...convection is expected to develop within a region of
decent CAPE and precipitable water values in excess of 2 standard
deviations above climatology. Except for some mid-level westerly
flow around the Great Lakes to provide some shear there...the flow
farther south should be fairly meager (but offset by steeper low-
level lapse rates). This sets up the potential for some local
rainfall rates in excess of 1 inch per hour that results in
excessive rainfall from the southern Plains east/northeastward into
the Ohio Valley and parts of the Mid- Atlantic region today and
tonight.

Some details are coming into focus, which includes the
likelihood of overnight convection lingering into the early-morning
hours across parts of the central Plains and Mid- Mississippi
Valley. Meanwhile, an upper trough lingering across the Southeast
will continue to foster an area of convergence on the
southern/southwestern periphery which could lead to locally heavy
rainfall along the eastern Gulf Coast and much of the northern
Florida Gulf Coast. There is some potential for extremely heavy
rainfall within this tropical airmass and precipitable water values
between 2.25 inches and 2.5 inches, but the signal from the
numerical guidance is that most rainfall to occur over the Gulf
waters at this time.

Farther north into the Ohio Valley, Appalachians and Northeast, a
weakening surface boundary will help focus some of the threat for
heavier rainfall with its placement remaining quite uncertain. The
synoptic setup with a stationary/warm front stretching across
southern PA and an approaching cold front from the west should help
foster greater coverage in showers/storms within a moist
environment, but storm motions within a mean column wind of 30kts
could limit the flooding threat even though this area remains
sensitive to intense rainfall.

Snell/Bann

Day 2
Valid 12Z Tue Jul 01 2025 - 12Z Wed Jul 02 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL OVER A PORTION OF
THE MID ATLANTIC AND NORTHEAST...

...2030Z Update...
The Slight Risk was expanded across the Mid-Atlantic and Northeast
ahead of the cold front. Thunderstorms across the region today are
expected to "prime" soils across the region, which are already well
above average according to NASA SPoRT 0-40 cm soil moisture
percentiles. By early tomorrow afternoon, slow moving cold front
and right entrance region ascent are forecast to drive widespread
thunderstorms within an airmass characterized by PWAT values in the
97-99th percentile per the NAEFS. While individual cell motions
will likely be progressive (15-30 kts), steering flow oriented
parallel to the forcing should favor periods of cell training and
repeating ahead of the cold front. Both the 12Z HREF and REFS
neighborhood probabilities highlight a high (60-90%) chance of 24
hour QPF exceeding three inches across the area, with embedded 30-40%
maxima of at least five inches noted. Considerable to locally
significant flash flooding is possible tomorrow within sensitive
urban areas along the I-95 corridor, and over complex terrain in
the Appalachians.

Asherman

...PREVIOUS DISCUSSION...

The boundary that helps focus some of the threat for heavy to
potentially excessive rainfall on Day 1 will continue to shift
eastward and provide the focus for another round on Day 2. The
flow aloft becomes more supportive over the Northeast US as
divergence aloft increases in response to a digging trough in the
upper level while convergence is focused at the low-levels
convergence increases along the boundary. Portions of the Mid-
Atlantic have suppressed Flash Flood Guidance from a period of
above normal rainfall making that area a bit more susceptible to
excessive rainfall...while faster cell motions should generally
preclude more than isolated instances of flash flooding across the
Northeast US. The inherited Slight Risk was nudged a bit to the
west of its placement in the previous outlook towards a region of
better overlap between the deterministic QPF and the lower flash
flood guidance. The surrounding Marginal Risk area was changed
little from the previous outlook.

Farther south/west along the boundary...convection is expected to
be develop within a region of decent CAPE and precipitable water
values in excess of 2 standard deviations above climatology. With
weaker flow aloft...locally heavy rainfall totals could result in
isolated instances of excessive rainfall. A stronger push of
moisture is expected into the Four Corners by Tuesday in response
to tropical moisture pushing northwestward across Mexico and
lifting to the east of a closed low churning near the California
coast. This could lead to greater thunderstorm coverage across the Southwest/Four Corners on Tuesday and a broader isolated flash
flooding threat.

Bann/Snell


Day 3
Valid 12Z Wed Jul 02 2025 - 12Z Thu Jul 03 2025

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL OVER PORTIONS OF
THE SOUTHEAST US AND ACROSS PARTS OF THE SOUTHERN HIGH PLAINS AND
NEARBY SOUTHERN ROCKIES...

...2030Z Update...
Generally minor adjustments made to the overnight forecast,
including an expansion of the Marginal Risk into parts of the Mid-
Atlantic. Lingering heavy rainfall potential will remain as the
front slowly presses southeastward, driving additional showers and thunderstorms with 90th percentile PWATs which could overlap with
heavy rainfall from days 1-2.

The Marginal was also expanded in the Southern Rockies based on the
uptick in QPF as an upper-trough approaches from the west, while
southeasterly flow ushers in 97th-99th percentile PWATs into the
region.

Asherman/Bann

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!5UN2xP3tRnLB2Jwzv-iluxjXjolpzUmNFH0RpGz7TKv6= dRCbdiIA9eGJpZNiYblct7UtXd1xD4T_bF1BloLQTaqiTaE$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!5UN2xP3tRnLB2Jwzv-iluxjXjolpzUmNFH0RpGz7TKv6= dRCbdiIA9eGJpZNiYblct7UtXd1xD4T_bF1BloLQlaOGl6A$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!5UN2xP3tRnLB2Jwzv-iluxjXjolpzUmNFH0RpGz7TKv6= dRCbdiIA9eGJpZNiYblct7UtXd1xD4T_bF1BloLQ3AI0p6M$=20

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FOUS30 KWBC 010826
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
426 AM EDT Tue Jul 1 2025

Day 1
Valid 12Z Tue Jul 01 2025 - 12Z Wed Jul 02 2025

..THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL OVER NORTHERN
PORTIONS OF THE MID-ATLANTIC REGION...

...Eastern Seaboard...

Per collaboration with WFOs CTP, PHI, and LWX, we have included a
Moderate Risk to the Day 1 ERO across parts of the northern Mid
Atlantic Region to include NoVa and the DC-Balt metro regions,
northern DE and into southeast PA.=20

Longwave upper trough over the Upper Great Lakes/Midwest early=20
this morning will pivot eastward Tue-Tue night, pushing east of the Appalachians Wed morning. Embedded within the longwave trough is a
shortwave, currently along the IA/IL/MO tri- state area, which=20
will track across the OH Valley later this afternoon and across the
Mid Atlantic later this evening and overnight. This shortwave=20
should enhance the broad- scale across the Mid Atlantic region=20
(especially), while low-level frontogenesis also gets a boost south
of the 90-100kt upper jet streak in the lee of the large-scale=20
trough.=20

0-6km bulk shear values increasing to 25+ kts within the inherited
broad Slight Risk area (30-40+ knots over the northern Mid Atlantic
into the Northeast) will support the formation of
widespread/multi-cluster line segments ahead of the upper
trough/surface cold front during peak diurnal instability hours=20
this afternoon into the evening. MUCAPEs peak between 2000-3000=20
J/Kg, while TPWs remain around 2 standard deviations above normal
for early July (between 2.00-2.25" within the non-convective
environment across much of the Mid Atlantic into southern New
England). The concern over the Slight and especially Moderate Risk
areas will be with upwind propagation and cell training, as the=20
pre-frontal southwesterly low-level flow (20-25 kts at 850 mb
becomes nearly parallel and of similar magnitude as the mean
850-300 mb flow. 00Z HREF and RRFS probabilities of 24hr QPF=20
exceeding 3" climb above 60% within much of the Moderate Risk=20
area (highest with the RRFS), while probs exceeding 5" within the=20
24hr period reach 40-60% in spots per the RRFS (though 20-25% tops=20
per the HREF). Given the favorable thermodynamic profile (high
CAPE/PW environment) along with the broad-scale forcing, anticipate
areas of 2 to 3+ inch/hr rainfall rates this afternoon and evening.=20

The Moderate Risk area also encompasses areas recently hit by
heavier rainfall, evidenced by the lower FFGs (in some areas, 1 hr
FFGs 1.00" or less). This includes areas SE PA including the=20 Middletown/Lancaster/Lebanon/Redding areas that received 4-7" of=20
rain on Monday.

...West Texas into New Mexico...

Farther south/west along the stalled frontal boundary...convection
is expected to be develop within a region of decent CAPE and=20
precipitable water values in excess of 2 standard deviations above=20 climatology. This area will also benefit from weak upper level
vorticity/shear axis within the broad-scale ridge, with tropical
moisture feeding in per the low-mid layer southeasterly flow.
850-700 mb moisture transport is pretty solid across the outlook
areas, but especially within the Slight Risk region across parts of
West TX into southeast NM where the 850-700 mb moisture flux
standardized anomalies peak between 3-4 standard deviations above
normal per the 00Z SREF and GEFS. Given the relatively healthy
low-level flow compared to the overall weaker mean flow, areas of=20
heavy, possibly excessive rainfall are anticipated, especially=20
within the Slight Risk area, considering the uptick in upwind
propagation and thus chances for cell training.=20

...South Texas...

An influx of abnormally high TPW from the remnants of Tropical
Cyclone Barry (2.2 to 2.4", which is close to 3 standard=20
deviations above normal for early July) will combine with a
modestly unstable environment (MUCAPEs increasing to 1500-2500
J/Kg) in producing very heavy short-term rainfall rates later this afternoon/evening and potentially later into the overnight period.
Both the HREF and RRFS ensembles show high probabilities (>50%) of
3+ inch rainfall, with 30-40% probs of exceeding 5 inches.
Therefore expect more than a localized risk of flash flooding=20
(i.e. Slight vs Marginal) across portions of South Texas from
Corpus Christi south through Brownsville and the RGV.

Hurley


Day 2
Valid 12Z Wed Jul 02 2025 - 12Z Thu Jul 03 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS OF
SOUTHEAST VIRGINIA AND NORTHEAST NORTH CAROLINA...

...Lower Mid Atlantic and Southeast...

Pre-frontal convection will likely be ongoing across the Mid=20
Atlantic and Southeastern Seaboard Wednesday morning, with=20
additional line segments upstream as well prior to the passage of=20
the surface front and upper trough axis later in the day. Along the
axis of 2.25"+ TPWs, by early afternoon (17-18Z), both the HREF=20
and RRFS ensembles show an uptick in >2"/hr rainfall rates across=20
southeast VA and northeast NC, particularly the RRFS (25-50%).=20
Available high-res CAM guidance (NAM Nest, FV3, and RRFS) all show=20
pockets of 3-5+ inch totals within the Slight Risk area. Elsewhere=20
within the Marginal Risk area stretching through much of the=20
Southeast, anticipate the flash flood threat to be more=20
isolated/localized as 0-6 km bulk shear values remain aob 20kt=20
(implying more pulse/less organized convection).

...West Texas into parts of the Southwest...
Continued moist, southeasterly low-level flow (850-700 moisture
transport/flux standardized anomalies +3 to +4 again from West TX
into NM) will set the stage for numerous showers and storms again,
especially during peak heating hours Wed afternoon and evening.
Strong low-level inflow is in some areas double the mean 850-300 mb
flow, thus resulting in Corfidi vectors opposing the low-level
wind. This will likely lead to cell training, especially where the southeasterly low-level flow leads to more upslope enhancement.
Right now, the guidance (including the CAMs that go out through
Day 2) show considerable spread with the heavier QPF. Therefore for
now will maintain a more isolated (Marginal) flash flood risk, as
later shifts will evaluate once the period (Wed-Wed night) gets=20
within the remainder of the high-res CAM windows.

Hurley

Day 3
Valid 12Z Thu Jul 03 2025 - 12Z Fri Jul 04 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS WESTERN
PORTIONS OF THE FLORIDA PENINSULA...

...Southern Georgia through northern and central Florida...

Subtle changes were made to the Slight and Marginal Risk areas
inherited from yesterday's Day 4 ERO. Southern periphery of the
longwave upper trough crosses the area Thu-Thu night, with the
guidance showing embedded shortwaves (possibly convectively-
enhanced) reaching South FL toward the end of the period (12Z Fri).
Ahead of the nearly stationary surface front, onshore west to=20
southwest low-level inflow from the eastern Gulf will likely lead
to a more focused area of low-level moisture transport/flux
convergence over much of the west coast of FL, especially north of
Ft. Myers to include the Tampa-St. Pete area, where 0-6km bulk=20
shear values do approach 25 kts (allowing for more=20
organized/widespread convective clusters). The RRFS is most=20
particularly robust with the QPF within the Slight Risk area (areas
of 3-6+ inches), which considering the thermodynamic=20
environment/deep subtropical moisture (TPW values 2.25 to 2.50"),=20
is certainly plausible. Especially considering the onshore low-=20
level inflow will likely exceed (perhaps double) the mean 850-300=20
mb wind), enhancing the potential for cell training. Even with a
more limited (tall/skinny) CAPE profile, sub-hourly rainfall rates
of 2.5-3.0+ inches within this environment will be possible,
especially within the Slight Risk area.=20

Elsewhere, few changes were made to the inherited Marginal Risk
area across the Northern Plains-Upper MS Valley and again across
West TX into the Southwest (including southern-central Rockies).
Guidance at this point shows considerable spread to support
anything more than a Marginal.=20

Hurley

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!6dVeQxKf3iehOExrlPRXLPpNhftJueSF5xGhVuteiulI= PfYigG_4EcwhJu28Fhi5rco4w0evK06CdjQE4lo8ndr5rqw$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!6dVeQxKf3iehOExrlPRXLPpNhftJueSF5xGhVuteiulI= PfYigG_4EcwhJu28Fhi5rco4w0evK06CdjQE4lo8qx0W8Jo$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!6dVeQxKf3iehOExrlPRXLPpNhftJueSF5xGhVuteiulI= PfYigG_4EcwhJu28Fhi5rco4w0evK06CdjQE4lo8SvOXRoM$=20

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FOUS30 KWBC 011330
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
930 AM EDT Tue Jul 1 2025

Day 1
Valid 1327Z Tue Jul 01 2025 - 12Z Wed Jul 02 2025

..THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL OVER NORTHERN
PORTIONS OF THE MID-ATLANTIC REGION...

1330Z Update: MCV moving across the Ohio Valley will be a focus of
heavy rainfall over portions of Southern and Southeast OH,=20
shifting into Southwest PA and Northern WV by the afternoon and
evening. Considering the ongoing threat with localized maxima
likely to spur scattered flash flood signals near the organized
complex, an earlier expansion of the SLGT risk was made to include
areas likely to be impacted now through the afternoon and early
evening time frame. Full update for rest of forecast will be out no
later than 16z.=20

Kleebauer

...Eastern Seaboard...

Per collaboration with WFOs CTP, PHI, and LWX, we have included a
Moderate Risk to the Day 1 ERO across parts of the northern Mid
Atlantic Region to include NoVa and the DC-Balt metro regions,
northern DE and into southeast PA.

Longwave upper trough over the Upper Great Lakes/Midwest early
this morning will pivot eastward Tue-Tue night, pushing east of the Appalachians Wed morning. Embedded within the longwave trough is a
shortwave, currently along the IA/IL/MO tri- state area, which
will track across the OH Valley later this afternoon and across the
Mid Atlantic later this evening and overnight. This shortwave
should enhance the broad- scale across the Mid Atlantic region
(especially), while low-level frontogenesis also gets a boost south
of the 90-100kt upper jet streak in the lee of the large-scale
trough.

0-6km bulk shear values increasing to 25+ kts within the inherited
broad Slight Risk area (30-40+ knots over the northern Mid Atlantic
into the Northeast) will support the formation of
widespread/multi-cluster line segments ahead of the upper
trough/surface cold front during peak diurnal instability hours
this afternoon into the evening. MUCAPEs peak between 2000-3000
J/Kg, while TPWs remain around 2 standard deviations above normal
for early July (between 2.00-2.25" within the non-convective
environment across much of the Mid Atlantic into southern New
England). The concern over the Slight and especially Moderate Risk
areas will be with upwind propagation and cell training, as the
pre-frontal southwesterly low-level flow (20-25 kts at 850 mb
becomes nearly parallel and of similar magnitude as the mean
850-300 mb flow. 00Z HREF and RRFS probabilities of 24hr QPF
exceeding 3" climb above 60% within much of the Moderate Risk
area (highest with the RRFS), while probs exceeding 5" within the
24hr period reach 40-60% in spots per the RRFS (though 20-25% tops
per the HREF). Given the favorable thermodynamic profile (high
CAPE/PW environment) along with the broad-scale forcing, anticipate
areas of 2 to 3+ inch/hr rainfall rates this afternoon and evening.

The Moderate Risk area also encompasses areas recently hit by
heavier rainfall, evidenced by the lower FFGs (in some areas, 1 hr
FFGs 1.00" or less). This includes areas SE PA including the Middletown/Lancaster/Lebanon/Redding areas that received 4-7" of
rain on Monday.

...West Texas into New Mexico...

Farther south/west along the stalled frontal boundary...convection
is expected to be develop within a region of decent CAPE and
precipitable water values in excess of 2 standard deviations above
climatology. This area will also benefit from weak upper level
vorticity/shear axis within the broad-scale ridge, with tropical
moisture feeding in per the low-mid layer southeasterly flow.
850-700 mb moisture transport is pretty solid across the outlook
areas, but especially within the Slight Risk region across parts of
West TX into southeast NM where the 850-700 mb moisture flux
standardized anomalies peak between 3-4 standard deviations above
normal per the 00Z SREF and GEFS. Given the relatively healthy
low-level flow compared to the overall weaker mean flow, areas of
heavy, possibly excessive rainfall are anticipated, especially
within the Slight Risk area, considering the uptick in upwind
propagation and thus chances for cell training.

...South Texas...

An influx of abnormally high TPW from the remnants of Tropical
Cyclone Barry (2.2 to 2.4", which is close to 3 standard
deviations above normal for early July) will combine with a
modestly unstable environment (MUCAPEs increasing to 1500-2500
J/Kg) in producing very heavy short-term rainfall rates later this afternoon/evening and potentially later into the overnight period.
Both the HREF and RRFS ensembles show high probabilities (>50%) of
3+ inch rainfall, with 30-40% probs of exceeding 5 inches.
Therefore expect more than a localized risk of flash flooding
(i.e. Slight vs Marginal) across portions of South Texas from
Corpus Christi south through Brownsville and the RGV.

Hurley


Day 2
Valid 12Z Wed Jul 02 2025 - 12Z Thu Jul 03 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS OF
SOUTHEAST VIRGINIA AND NORTHEAST NORTH CAROLINA...

...Lower Mid Atlantic and Southeast...

Pre-frontal convection will likely be ongoing across the Mid
Atlantic and Southeastern Seaboard Wednesday morning, with
additional line segments upstream as well prior to the passage of
the surface front and upper trough axis later in the day. Along the
axis of 2.25"+ TPWs, by early afternoon (17-18Z), both the HREF
and RRFS ensembles show an uptick in >2"/hr rainfall rates across
southeast VA and northeast NC, particularly the RRFS (25-50%).
Available high-res CAM guidance (NAM Nest, FV3, and RRFS) all show
pockets of 3-5+ inch totals within the Slight Risk area. Elsewhere
within the Marginal Risk area stretching through much of the
Southeast, anticipate the flash flood threat to be more
isolated/localized as 0-6 km bulk shear values remain aob 20kt
(implying more pulse/less organized convection).

...West Texas into parts of the Southwest...
Continued moist, southeasterly low-level flow (850-700 moisture
transport/flux standardized anomalies +3 to +4 again from West TX
into NM) will set the stage for numerous showers and storms again,
especially during peak heating hours Wed afternoon and evening.
Strong low-level inflow is in some areas double the mean 850-300 mb
flow, thus resulting in Corfidi vectors opposing the low-level
wind. This will likely lead to cell training, especially where the southeasterly low-level flow leads to more upslope enhancement.
Right now, the guidance (including the CAMs that go out through
Day 2) show considerable spread with the heavier QPF. Therefore for
now will maintain a more isolated (Marginal) flash flood risk, as
later shifts will evaluate once the period (Wed-Wed night) gets
within the remainder of the high-res CAM windows.

Hurley

Day 3
Valid 12Z Thu Jul 03 2025 - 12Z Fri Jul 04 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS WESTERN
PORTIONS OF THE FLORIDA PENINSULA...

...Southern Georgia through northern and central Florida...

Subtle changes were made to the Slight and Marginal Risk areas
inherited from yesterday's Day 4 ERO. Southern periphery of the
longwave upper trough crosses the area Thu-Thu night, with the
guidance showing embedded shortwaves (possibly convectively-
enhanced) reaching South FL toward the end of the period (12Z Fri).
Ahead of the nearly stationary surface front, onshore west to
southwest low-level inflow from the eastern Gulf will likely lead
to a more focused area of low-level moisture transport/flux
convergence over much of the west coast of FL, especially north of
Ft. Myers to include the Tampa-St. Pete area, where 0-6km bulk
shear values do approach 25 kts (allowing for more
organized/widespread convective clusters). The RRFS is most
particularly robust with the QPF within the Slight Risk area (areas
of 3-6+ inches), which considering the thermodynamic
environment/deep subtropical moisture (TPW values 2.25 to 2.50"),
is certainly plausible. Especially considering the onshore low-
level inflow will likely exceed (perhaps double) the mean 850-300
mb wind), enhancing the potential for cell training. Even with a
more limited (tall/skinny) CAPE profile, sub-hourly rainfall rates
of 2.5-3.0+ inches within this environment will be possible,
especially within the Slight Risk area.

Elsewhere, few changes were made to the inherited Marginal Risk
area across the Northern Plains-Upper MS Valley and again across
West TX into the Southwest (including southern-central Rockies).
Guidance at this point shows considerable spread to support
anything more than a Marginal.

Hurley

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!_U8Podd8rG6uhAy2Lh_0EuvKD16ibKqNr7eXRozk4Xeo= oxD5mWtdjL0Xdw02jUCIg0bg5qhajywmo9QxNkGW-AXIzfw$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!_U8Podd8rG6uhAy2Lh_0EuvKD16ibKqNr7eXRozk4Xeo= oxD5mWtdjL0Xdw02jUCIg0bg5qhajywmo9QxNkGW9THg2Og$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!_U8Podd8rG6uhAy2Lh_0EuvKD16ibKqNr7eXRozk4Xeo= oxD5mWtdjL0Xdw02jUCIg0bg5qhajywmo9QxNkGWlifiPP0$=20

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FOUS30 KWBC 011543
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
1143 AM EDT Tue Jul 1 2025

Day 1
Valid 16Z Tue Jul 01 2025 - 12Z Wed Jul 02 2025

..THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL OVER NORTHERN
PORTIONS OF THE MID-ATLANTIC REGION...

...Northeast through Ohio Valley...

16Z Update: The threat for the Mid Atlantic remains locked in for
the D1 with the MDT risk maintained over the previous areas, but
allowed for an expansion on the northeast flank to encompass all of
the Philadelphia metro, including adjacent areas of Southern NJ.
12z KIAD sounding has come in with a robust 2.07" PWAT, a daily
record for 7/1. The wet bulb zero height is also a daily record
indicating a particularly deep warm-cloud layer situated within the
lower troposphere. This type of environment along with a well-
defined tall, skinny CAPE signature is representative of a strong
prospect for not only heavy rainfall, but significant rate driven
rain cores (2-3+"/hr) that can efficiently drop several inches of=20
rain in a short span of time. The area encompassing the Central Mid
Atlantic has a variety of factors for enhancing the potential=20
(urbanization, antecedent moist grounds), but enhanced rates=20
increase the threat by a respectable margin and historically points
to a higher flash flood threat in both coverage and magnitude for=20
a period. Recent CAMs are very much depicting several small QPF=20
maxima littered over the Mid Atlantic with the highest signals=20
positioned over Northern VA up through the MD Piedmont and points=20 east-northeast. The alignment of the heavier QPF situated over=20
Southeast PA into Northern DE and Southern NJ is likely in part to=20
a targeted convective initiation and training point within a narrow
sheared surface trough situated over the region as noted via the=20
latest visible sat channels. The assessment this morning only=20
provided greater credence to the threat with the previous=20
discussion still well in-play in the overall outline of an elevated
risk for flash flooding. Given some of the latest trends within the
QPF and mesoscale evolution this morning, the MDT risk expansion
through more of Southeast PA into Southern and Central NJ was=20
generated.

Higher end SLGT risk is now forecast across much of WV as locally=20
heavy rainfall with potential for up to 2-2.5"/hr rates will likely
cause problems within the complex terrain as funneling effects=20
tend to exacerbate any convective threat in the state. This threat
extends into far Southwest PA with focus around the periphery of=20
an advancing MCV currently migrating through Southern OH.=20

Kleebauer

..Previous Discussion..
Per collaboration with WFOs CTP, PHI, and LWX, we have included a=20
Moderate Risk to the Day 1 ERO across parts of the northern Mid=20
Atlantic Region to include NoVa and the DC-Balt metro regions,=20
northern DE and into southeast PA.

Longwave upper trough over the Upper Great Lakes/Midwest early
this morning will pivot eastward Tue-Tue night, pushing east of the Appalachians Wed morning. Embedded within the longwave trough is a
shortwave, currently along the IA/IL/MO tri- state area, which
will track across the OH Valley later this afternoon and across the
Mid Atlantic later this evening and overnight. This shortwave
should enhance the broad- scale across the Mid Atlantic region
(especially), while low-level frontogenesis also gets a boost south
of the 90-100kt upper jet streak in the lee of the large-scale
trough.

0-6km bulk shear values increasing to 25+ kts within the inherited
broad Slight Risk area (30-40+ knots over the northern Mid Atlantic
into the Northeast) will support the formation of
widespread/multi-cluster line segments ahead of the upper
trough/surface cold front during peak diurnal instability hours
this afternoon into the evening. MUCAPEs peak between 2000-3000
J/Kg, while TPWs remain around 2 standard deviations above normal
for early July (between 2.00-2.25" within the non-convective
environment across much of the Mid Atlantic into southern New
England). The concern over the Slight and especially Moderate Risk
areas will be with upwind propagation and cell training, as the
pre-frontal southwesterly low-level flow (20-25 kts at 850 mb
becomes nearly parallel and of similar magnitude as the mean
850-300 mb flow. 00Z HREF and RRFS probabilities of 24hr QPF
exceeding 3" climb above 60% within much of the Moderate Risk
area (highest with the RRFS), while probs exceeding 5" within the
24hr period reach 40-60% in spots per the RRFS (though 20-25% tops
per the HREF). Given the favorable thermodynamic profile (high
CAPE/PW environment) along with the broad-scale forcing, anticipate
areas of 2 to 3+ inch/hr rainfall rates this afternoon and evening.

The Moderate Risk area also encompasses areas recently hit by
heavier rainfall, evidenced by the lower FFGs (in some areas, 1 hr
FFGs 1.00" or less). This includes areas SE PA including the Middletown/Lancaster/Lebanon/Redding areas that received 4-7" of
rain on Monday.

Hurley

...West Texas into New Mexico...

16Z Update: The current SLGT risk was generally maintained with
only a minor expansion to the east to include more of the Western
Rolling Plains adjacent to the Concho Valley. Quasi-stationary
front will be the focal point later this afternoon and evening with
typical diurnal heat flux providing greater buoyancy with the
regional environment allowing for several thunderstorms to develop
in proxy to the boundary. 12z KMAF sounding was right up against
the daily record for PWATs and well beyond the 90th percentile for
the date meaning the environment is ripe for locally heavy precip
potential once the convective regime initiates. 12z HREF probs are
robust for both the neighborhood >2" indicator and the >1" EAS
field which notes a "bullseye" of up to 50% located over parts
of the Upper Trans Pecos into the adjacent Guadalupe Mtns. The
other area of concern will lie within that quasi-stationary front
with a elevated signature for >2" situated from the NM/TX border,
east across the Northern Permian Basin. Enhanced hourly rates will
be the primary threat for the period with 1-2"/hr rates very likely
in any strong convective cores. Look for scattered flash flood
signals within the above zones with the greatest threat positioned
over Southeast NM and adjacent TX Caprock as noted in the QPF/prob
fields.=20

Kleebauer

..Previous Discussion..=20

Farther south/west along the stalled frontal boundary...convection
is expected to be develop within a region of decent CAPE and
precipitable water values in excess of 2 standard deviations above
climatology. This area will also benefit from weak upper level
vorticity/shear axis within the broad-scale ridge, with tropical
moisture feeding in per the low-mid layer southeasterly flow.
850-700 mb moisture transport is pretty solid across the outlook
areas, but especially within the Slight Risk region across parts of
West TX into southeast NM where the 850-700 mb moisture flux
standardized anomalies peak between 3-4 standard deviations above
normal per the 00Z SREF and GEFS. Given the relatively healthy
low-level flow compared to the overall weaker mean flow, areas of
heavy, possibly excessive rainfall are anticipated, especially
within the Slight Risk area, considering the uptick in upwind
propagation and thus chances for cell training.

Hurley

...South Texas...

16Z Update: Only minor adjustments necessary for the SLGT risk
across Deep South TX as the previous forecast remains on track.
Little deviation in the prob fields from overnight allowed for a
continuation of the SLGT risk with emphasis on greatest threat
likely over the Lower RGV, including the cities of Brownsville and
McAllen.=20

Kleebauer

..Previous Discussion..

An influx of abnormally high TPW from the remnants of Tropical
Cyclone Barry (2.2 to 2.4", which is close to 3 standard
deviations above normal for early July) will combine with a
modestly unstable environment (MUCAPEs increasing to 1500-2500
J/Kg) in producing very heavy short-term rainfall rates later this afternoon/evening and potentially later into the overnight period.
Both the HREF and RRFS ensembles show high probabilities (>50%) of
3+ inch rainfall, with 30-40% probs of exceeding 5 inches.
Therefore expect more than a localized risk of flash flooding
(i.e. Slight vs Marginal) across portions of South Texas from
Corpus Christi south through Brownsville and the RGV.

Hurley


Day 2
Valid 12Z Wed Jul 02 2025 - 12Z Thu Jul 03 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS OF
SOUTHEAST VIRGINIA AND NORTHEAST NORTH CAROLINA...

...Lower Mid Atlantic and Southeast...

Pre-frontal convection will likely be ongoing across the Mid
Atlantic and Southeastern Seaboard Wednesday morning, with
additional line segments upstream as well prior to the passage of
the surface front and upper trough axis later in the day. Along the
axis of 2.25"+ TPWs, by early afternoon (17-18Z), both the HREF
and RRFS ensembles show an uptick in >2"/hr rainfall rates across
southeast VA and northeast NC, particularly the RRFS (25-50%).
Available high-res CAM guidance (NAM Nest, FV3, and RRFS) all show
pockets of 3-5+ inch totals within the Slight Risk area. Elsewhere
within the Marginal Risk area stretching through much of the
Southeast, anticipate the flash flood threat to be more
isolated/localized as 0-6 km bulk shear values remain aob 20kt
(implying more pulse/less organized convection).

...West Texas into parts of the Southwest...
Continued moist, southeasterly low-level flow (850-700 moisture
transport/flux standardized anomalies +3 to +4 again from West TX
into NM) will set the stage for numerous showers and storms again,
especially during peak heating hours Wed afternoon and evening.
Strong low-level inflow is in some areas double the mean 850-300 mb
flow, thus resulting in Corfidi vectors opposing the low-level
wind. This will likely lead to cell training, especially where the southeasterly low-level flow leads to more upslope enhancement.
Right now, the guidance (including the CAMs that go out through
Day 2) show considerable spread with the heavier QPF. Therefore for
now will maintain a more isolated (Marginal) flash flood risk, as
later shifts will evaluate once the period (Wed-Wed night) gets
within the remainder of the high-res CAM windows.

Hurley

Day 3
Valid 12Z Thu Jul 03 2025 - 12Z Fri Jul 04 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS WESTERN
PORTIONS OF THE FLORIDA PENINSULA...

...Southern Georgia through northern and central Florida...

Subtle changes were made to the Slight and Marginal Risk areas
inherited from yesterday's Day 4 ERO. Southern periphery of the
longwave upper trough crosses the area Thu-Thu night, with the
guidance showing embedded shortwaves (possibly convectively-
enhanced) reaching South FL toward the end of the period (12Z Fri).
Ahead of the nearly stationary surface front, onshore west to
southwest low-level inflow from the eastern Gulf will likely lead
to a more focused area of low-level moisture transport/flux
convergence over much of the west coast of FL, especially north of
Ft. Myers to include the Tampa-St. Pete area, where 0-6km bulk
shear values do approach 25 kts (allowing for more
organized/widespread convective clusters). The RRFS is most
particularly robust with the QPF within the Slight Risk area (areas
of 3-6+ inches), which considering the thermodynamic
environment/deep subtropical moisture (TPW values 2.25 to 2.50"),
is certainly plausible. Especially considering the onshore low-
level inflow will likely exceed (perhaps double) the mean 850-300
mb wind), enhancing the potential for cell training. Even with a
more limited (tall/skinny) CAPE profile, sub-hourly rainfall rates
of 2.5-3.0+ inches within this environment will be possible,
especially within the Slight Risk area.

Elsewhere, few changes were made to the inherited Marginal Risk
area across the Northern Plains-Upper MS Valley and again across
West TX into the Southwest (including southern-central Rockies).
Guidance at this point shows considerable spread to support
anything more than a Marginal.

Hurley

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!-GySDotozYJ3ObXvz90yAVo3TrA7qtFqIgyLo9hlLql1= 78beikoz5RiLyF0BzneQjF2Yw4RXzKB4i9NqJingkbknkPg$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!-GySDotozYJ3ObXvz90yAVo3TrA7qtFqIgyLo9hlLql1= 78beikoz5RiLyF0BzneQjF2Yw4RXzKB4i9NqJingh5sPhyY$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!-GySDotozYJ3ObXvz90yAVo3TrA7qtFqIgyLo9hlLql1= 78beikoz5RiLyF0BzneQjF2Yw4RXzKB4i9NqJingEBRXkmo$=20

=3D =3D =3D
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FOUS30 KWBC 012023
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
423 PM EDT Tue Jul 1 2025

Day 1
Valid 16Z Tue Jul 01 2025 - 12Z Wed Jul 02 2025

..THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL OVER NORTHERN
PORTIONS OF THE MID-ATLANTIC REGION...

...Northeast through Ohio Valley...

16Z Update: The threat for the Mid Atlantic remains locked in for
the D1 with the MDT risk maintained over the previous areas, but
allowed for an expansion on the northeast flank to encompass all of
the Philadelphia metro, including adjacent areas of Southern NJ.
12z KIAD sounding has come in with a robust 2.07" PWAT, a daily
record for 7/1. The wet bulb zero height is also a daily record
indicating a particularly deep warm-cloud layer situated within the
lower troposphere. This type of environment along with a well-
defined tall, skinny CAPE signature is representative of a strong
prospect for not only heavy rainfall, but significant rate driven
rain cores (2-3+"/hr) that can efficiently drop several inches of
rain in a short span of time. The area encompassing the Central Mid
Atlantic has a variety of factors for enhancing the potential
(urbanization, antecedent moist grounds), but enhanced rates
increase the threat by a respectable margin and historically points
to a higher flash flood threat in both coverage and magnitude for
a period. Recent CAMs are very much depicting several small QPF
maxima littered over the Mid Atlantic with the highest signals
positioned over Northern VA up through the MD Piedmont and points east-northeast. The alignment of the heavier QPF situated over
Southeast PA into Northern DE and Southern NJ is likely in part to
a targeted convective initiation and training point within a narrow
sheared surface trough situated over the region as noted via the
latest visible sat channels. The assessment this morning only
provided greater credence to the threat with the previous
discussion still well in-play in the overall outline of an elevated
risk for flash flooding. Given some of the latest trends within the
QPF and mesoscale evolution this morning, the MDT risk expansion
through more of Southeast PA into Southern and Central NJ was
generated.

Higher end SLGT risk is now forecast across much of WV as locally
heavy rainfall with potential for up to 2-2.5"/hr rates will likely
cause problems within the complex terrain as funneling effects
tend to exacerbate any convective threat in the state. This threat
extends into far Southwest PA with focus around the periphery of
an advancing MCV currently migrating through Southern OH.

Kleebauer

..Previous Discussion..
Per collaboration with WFOs CTP, PHI, and LWX, we have included a
Moderate Risk to the Day 1 ERO across parts of the northern Mid
Atlantic Region to include NoVa and the DC-Balt metro regions,
northern DE and into southeast PA.

Longwave upper trough over the Upper Great Lakes/Midwest early
this morning will pivot eastward Tue-Tue night, pushing east of the Appalachians Wed morning. Embedded within the longwave trough is a
shortwave, currently along the IA/IL/MO tri- state area, which
will track across the OH Valley later this afternoon and across the
Mid Atlantic later this evening and overnight. This shortwave
should enhance the broad- scale across the Mid Atlantic region
(especially), while low-level frontogenesis also gets a boost south
of the 90-100kt upper jet streak in the lee of the large-scale
trough.

0-6km bulk shear values increasing to 25+ kts within the inherited
broad Slight Risk area (30-40+ knots over the northern Mid Atlantic
into the Northeast) will support the formation of
widespread/multi-cluster line segments ahead of the upper
trough/surface cold front during peak diurnal instability hours
this afternoon into the evening. MUCAPEs peak between 2000-3000
J/Kg, while TPWs remain around 2 standard deviations above normal
for early July (between 2.00-2.25" within the non-convective
environment across much of the Mid Atlantic into southern New
England). The concern over the Slight and especially Moderate Risk
areas will be with upwind propagation and cell training, as the
pre-frontal southwesterly low-level flow (20-25 kts at 850 mb
becomes nearly parallel and of similar magnitude as the mean
850-300 mb flow. 00Z HREF and RRFS probabilities of 24hr QPF
exceeding 3" climb above 60% within much of the Moderate Risk
area (highest with the RRFS), while probs exceeding 5" within the
24hr period reach 40-60% in spots per the RRFS (though 20-25% tops
per the HREF). Given the favorable thermodynamic profile (high
CAPE/PW environment) along with the broad-scale forcing, anticipate
areas of 2 to 3+ inch/hr rainfall rates this afternoon and evening.

The Moderate Risk area also encompasses areas recently hit by
heavier rainfall, evidenced by the lower FFGs (in some areas, 1 hr
FFGs 1.00" or less). This includes areas SE PA including the Middletown/Lancaster/Lebanon/Redding areas that received 4-7" of
rain on Monday.

Hurley

...West Texas into New Mexico...

16Z Update: The current SLGT risk was generally maintained with
only a minor expansion to the east to include more of the Western
Rolling Plains adjacent to the Concho Valley. Quasi-stationary
front will be the focal point later this afternoon and evening with
typical diurnal heat flux providing greater buoyancy with the
regional environment allowing for several thunderstorms to develop
in proxy to the boundary. 12z KMAF sounding was right up against
the daily record for PWATs and well beyond the 90th percentile for
the date meaning the environment is ripe for locally heavy precip
potential once the convective regime initiates. 12z HREF probs are
robust for both the neighborhood >2" indicator and the >1" EAS
field which notes a "bullseye" of up to 50% located over parts
of the Upper Trans Pecos into the adjacent Guadalupe Mtns. The
other area of concern will lie within that quasi-stationary front
with a elevated signature for >2" situated from the NM/TX border,
east across the Northern Permian Basin. Enhanced hourly rates will
be the primary threat for the period with 1-2"/hr rates very likely
in any strong convective cores. Look for scattered flash flood
signals within the above zones with the greatest threat positioned
over Southeast NM and adjacent TX Caprock as noted in the QPF/prob
fields.

Kleebauer

..Previous Discussion..

Farther south/west along the stalled frontal boundary...convection
is expected to be develop within a region of decent CAPE and
precipitable water values in excess of 2 standard deviations above
climatology. This area will also benefit from weak upper level
vorticity/shear axis within the broad-scale ridge, with tropical
moisture feeding in per the low-mid layer southeasterly flow.
850-700 mb moisture transport is pretty solid across the outlook
areas, but especially within the Slight Risk region across parts of
West TX into southeast NM where the 850-700 mb moisture flux
standardized anomalies peak between 3-4 standard deviations above
normal per the 00Z SREF and GEFS. Given the relatively healthy
low-level flow compared to the overall weaker mean flow, areas of
heavy, possibly excessive rainfall are anticipated, especially
within the Slight Risk area, considering the uptick in upwind
propagation and thus chances for cell training.

Hurley

...South Texas...

16Z Update: Only minor adjustments necessary for the SLGT risk
across Deep South TX as the previous forecast remains on track.
Little deviation in the prob fields from overnight allowed for a
continuation of the SLGT risk with emphasis on greatest threat
likely over the Lower RGV, including the cities of Brownsville and
McAllen.

Kleebauer

..Previous Discussion..

An influx of abnormally high TPW from the remnants of Tropical
Cyclone Barry (2.2 to 2.4", which is close to 3 standard
deviations above normal for early July) will combine with a
modestly unstable environment (MUCAPEs increasing to 1500-2500
J/Kg) in producing very heavy short-term rainfall rates later this afternoon/evening and potentially later into the overnight period.
Both the HREF and RRFS ensembles show high probabilities (>50%) of
3+ inch rainfall, with 30-40% probs of exceeding 5 inches.
Therefore expect more than a localized risk of flash flooding
(i.e. Slight vs Marginal) across portions of South Texas from
Corpus Christi south through Brownsville and the RGV.

Hurley


Day 2
Valid 12Z Wed Jul 02 2025 - 12Z Thu Jul 03 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS OF
SOUTHEAST VIRGINIA AND NORTHEAST NORTH CAROLINA, WESTERN FLORIDA
COAST, AND THE SOUTHWESTERN U.S...

...Lower Mid Atlantic and Southeast...

20Z Update: The combination of elevated moisture on the order of=20
+1 to +2 deviation PWATs, relevant buoyancy, modest shear, and the
progression of a cold front from the northwest will aid in=20
sufficient convergence in-of the VA Tidewater down through Eastern=20
NC on Wednesday. PWATs encroaching 2.2-2.4" across the above region
will setup an environment capable of not only heavy rainfall, but=20
efficient warm rain processes that should maximize QPF in any=20
convective cores that materialize. 12z CAMs continue to depict=20
forecast soundings over the Southeast Mid Atlantic coast that=20
exhibit textbook tall, skinny CAPE signatures with a deep moisture=20
layer sampled from the surface to tropopause. 12z HREF neighborhood
probs for >3" were running between 70-90% over the area extending=20
from Williamsburg, VA down through Morehead City, NC with >5"=20
probs hovering between 25-40% with a bullseye of 50-60% over the=20
Hampton Roads area of Southeast VA. These signals are indicative of
locally heavy rainfall likely with an areal average of 1-2", at=20
the very least within the ensemble means. This allowed for a=20
general maintenance of the SLGT risk inherited with some minor=20
expansions to cover for the latest HREF blended mean QPF footprint.

Scattered heavy convection will also be forecast away from the
above area with the main threat likely more urbanized flash flood
concerns within any heavier cells as the environment is ripe for
locally heavy rainfall from the Central Gulf coast to points north
and northeast.=20

...Southwest...

20Z Update: Synoptic progression across the Southwestern CONUS=20
coupled with a deep, moist advection pattern further inland from=20
the southeast will lead to widespread convective development across
West TX, extending westward through the terrain of NM and AZ. A=20
stagnant upper trough/ULL centered off the CA coast will meander=20
over the next 24 hrs to the east before finally pushing further=20
inland and opening up into quite a prolific trough providing large=20
scale ascent to much of the Desert Southwest east of the Colorado=20
river basin. Presence of monsoonal moisture will be amplified=20
moving into Wednesday as the amplified flow from the approaching=20
trough and ridge positioning over the Four Corners will create the=20
textbook funneling affect of deeper moisture poleward through West=20
TX to points north and northwest. The highest PWAT anomalies will=20
be centered over Southeast NM, Southern NM, and the Mogollon Rim=20
creating a generally buoyant environment over the aforementioned=20
areas. With MUCAPE between 1000-2500 J/kg and PWAT anomalies ~2=20
deviations above normal as depicted via the ECENS and NAEFS=20
outputs, expectation is for scattered heavy convective cores=20
capable of hourly rates approaching 1"/hr with generally slow cell=20
motions leading to some training concerns across the terrain. 12z=20
HREF 24hr ARI exceedance probabilities are between 40-70% for=20
exceeding 10yr intervals and 10-30% for even some 100yr ARI=20
threats, a testament to the expected magnitude of precip falling=20
during the period. Locally 1-2" of rainfall within the area is=20
plenty to cause significant flash flood issues in any one area=20
across the Sacramento's through the terrain west and northwest.=20

There is enough evidence given the expected environment and
widespread convective regime for a broad SLGT risk positioned
across El Paso, Southern NM, Southeast AZ, and the Mogollon Rim
across Central AZ.=20

...Western Florida Coast...

20Z Update: The combination of a slow-moving frontal progression=20
and potential for weak surface reflection over the Eastern Gulf=20
will create a period of unsettled weather in-of the Western FL=20
Peninsula. The prospects for heavy rainfall capable of widespread=20
flash flood concerns is still on the lower end with the best threat
relegated to the urban zones along the coast with the best threat=20
likely over western Pasco and Hillsborough counties, along with=20
Pinellas county where the Tampa metro is the center of where the=20
threat lies. When assessing the hi-res guidance today, you would=20
think there's a chance of 10+ inches of rainfall along the coast,=20
but a lot of that precip stems from the CAMs struggling with the=20
surface reflection and likely enhancing the baroclinicity along the
front, an issue that has cropped up in the past. Other=20
deterministic members within the global suite are closer to 4-7"=20
for maxima with ensemble depiction closer to the lower end of the=20
range. This is subjective to a multitude of factors ranging from=20
frontal positioning, surface convergence, location of the low=20
proxy, and other finer mesoscale details. At the current look, the=20
threat is still within the threshold of higher risk, but low to=20
medium confidence considering some of the finer details. At this=20
juncture, with the PWATs and focal point necessary for locally=20
enhanced rainfall potential with rates pushing 3-5"/hr in stronger=20
cells in any location, and the urbanization concerns where the=20
heaviest rain will fall, a SLGT risk was added to the three=20
counties inferred above with the Tampa/Clearwater/St. Petersburg=20
metro the area of greatest concern. Will be a period to monitor for
shifts in the risk level, whether downgrade or upgrade.=20

Kleebauer


Day 3
Valid 12Z Thu Jul 03 2025 - 12Z Fri Jul 04 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS WESTERN
PORTIONS OF THE FLORIDA PENINSULA...

...Florida and Georgia...

20Z Update: Little changes was necessary for the SLGT risk across
the western FL coast as the previous forecast remains on track.
This period has the best consistency in the positioning and
magnitude of the heavy precip threat among the deterministic. As of
now, the risk is lower in terms of magnitude compared to what could
transpire in the D2, so the threat could be downgraded if the
previous periods doesn't materialize. However, overlap if the
threat D2 transpires would ultimately create a greater threat, so
some of the threat could be contingent on the evolution. ML is
consistent in its interpretation of the heavier rain positioned
between Clearwater down to Ft. Myers, so it's worth noting we have
a good signal for the location. It will be worth monitoring in the
coming days with plenty of time for any adjustments.=20

Kleebauer

..Previous Discussion..

Subtle changes were made to the Slight and Marginal Risk areas
inherited from yesterday's Day 4 ERO. Southern periphery of the
longwave upper trough crosses the area Thu-Thu night, with the
guidance showing embedded shortwaves (possibly convectively-
enhanced) reaching South FL toward the end of the period (12Z Fri).
Ahead of the nearly stationary surface front, onshore west to
southwest low-level inflow from the eastern Gulf will likely lead
to a more focused area of low-level moisture transport/flux
convergence over much of the west coast of FL, especially north of
Ft. Myers to include the Tampa-St. Pete area, where 0-6km bulk
shear values do approach 25 kts (allowing for more
organized/widespread convective clusters). The RRFS is most
particularly robust with the QPF within the Slight Risk area (areas
of 3-6+ inches), which considering the thermodynamic
environment/deep subtropical moisture (TPW values 2.25 to 2.50"),
is certainly plausible. Especially considering the onshore low-
level inflow will likely exceed (perhaps double) the mean 850-300
mb wind), enhancing the potential for cell training. Even with a
more limited (tall/skinny) CAPE profile, sub-hourly rainfall rates
of 2.5-3.0+ inches within this environment will be possible,
especially within the Slight Risk area.

Hurley

...Southern Plains to Southwest...

Continued deep moist advective pattern will lead to scattered or
even widespread thunderstorm activity over much of West TX up
through the Central Rockies as the upstream synoptic evolution of
the ejecting trough will create a pretty robust large scale ascent
signature across much of the CONUS west of the 100W marker. Still
some discrepancy on the eastern expansion of the heavier convective
threat with some guidance inferring the Concho Valley, others the
Permian Basin and Trans Pecos, and others as far west as Southwest
TX. Too much spread in the deterministic with the ensemble means
relatively modest in magnitude. As we move into CAMs range, expect
the signal to ramp up in the magnitude with a more defined axis of
heavy precip likely to allow for a targeted SLGT risk. Areas within
the Central Rockies will be evaluated in the coming days as well
with the core of the shortwave energy ejecting out of the
Southwest likely to motion overhead. This could be a target for
heavy rain prospects along the Southern Laramie Range down through
the Foothills of CO Rockies with some guidance depicting 2-3" of
rainfall in the period, something that could also spur an upgrade
in the risk with the environment in place. For now, a broad MRGL
risk encompasses much of the Southwest, Southern Plains, and
Central Rockies.

Kleebauer


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!8reLd31U_EfAbxCaARc1s8DDP1OBNgSDeetoJ9CqCS61= ukzehSH0pRjLfNEWr2EcdlUk16s2hjzBL6CTFzB_TLn6h-Y$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!8reLd31U_EfAbxCaARc1s8DDP1OBNgSDeetoJ9CqCS61= ukzehSH0pRjLfNEWr2EcdlUk16s2hjzBL6CTFzB_nWvMQN4$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!8reLd31U_EfAbxCaARc1s8DDP1OBNgSDeetoJ9CqCS61= ukzehSH0pRjLfNEWr2EcdlUk16s2hjzBL6CTFzB_rX3F_Z0$=20

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FOUS30 KWBC 020055
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
855 PM EDT Tue Jul 1 2025

Day 1
Valid 01Z Wed Jul 02 2025 - 12Z Wed Jul 02 2025

..THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL OVER NORTHERN=20
PORTIONS OF THE SOUTHEAST AND MID ATLANTIC...

...01Z Update...

With the heaviest rainfall having exited much of the northern Mid-
Atlantic, the Moderate Risk was dropped as of this update. However,
there remain no shortage of rich moisture aloft and modest
instability from the Deep South on north to the Mid-Atlantic
coast. The Slight Risk remains in place for these areas through
tonight. Rainfall gradually tapers off first in the more northern=20
and western portions of the Marginal and Slight Risk areas this
evening, followed by the more southern and eastern periphery of the
threat areas later tonight. Elsewhere, the Slight Risk in South
Texas was dropped given most hourly rainfall rates are coming in
less than 1"/hr. That said, RAP mesoanalysis still shows a large
area of 2.2-2.4" PWATs throughout South Texas, so opted to maintain
the Marginal Risk given any potential thunderstorms could possibly
muster up >2"/hr rainfall rates. The Marginal Risk was also trimmed
back in parts of southern GA and FL where the localized flash=20
flood threat is subsiding. Aside from some subtle adjustments via=20
radar trends and latest 18Z HREF guidance, the Marginal and Slight=20
Risks in portions of the Southwest and southern High Plains remain=20
in effect.=20

Mullinax


---Previous Discussion---

...Northeast through Ohio Valley...

16Z Update: The threat for the Mid Atlantic remains locked in for
the D1 with the MDT risk maintained over the previous areas, but
allowed for an expansion on the northeast flank to encompass all of
the Philadelphia metro, including adjacent areas of Southern NJ.
12z KIAD sounding has come in with a robust 2.07" PWAT, a daily
record for 7/1. The wet bulb zero height is also a daily record
indicating a particularly deep warm-cloud layer situated within the
lower troposphere. This type of environment along with a well-
defined tall, skinny CAPE signature is representative of a strong
prospect for not only heavy rainfall, but significant rate driven
rain cores (2-3+"/hr) that can efficiently drop several inches of
rain in a short span of time. The area encompassing the Central Mid
Atlantic has a variety of factors for enhancing the potential
(urbanization, antecedent moist grounds), but enhanced rates
increase the threat by a respectable margin and historically points
to a higher flash flood threat in both coverage and magnitude for
a period. Recent CAMs are very much depicting several small QPF
maxima littered over the Mid Atlantic with the highest signals
positioned over Northern VA up through the MD Piedmont and points east-northeast. The alignment of the heavier QPF situated over
Southeast PA into Northern DE and Southern NJ is likely in part to
a targeted convective initiation and training point within a narrow
sheared surface trough situated over the region as noted via the
latest visible sat channels. The assessment this morning only
provided greater credence to the threat with the previous
discussion still well in-play in the overall outline of an elevated
risk for flash flooding. Given some of the latest trends within the
QPF and mesoscale evolution this morning, the MDT risk expansion
through more of Southeast PA into Southern and Central NJ was
generated.

Higher end SLGT risk is now forecast across much of WV as locally
heavy rainfall with potential for up to 2-2.5"/hr rates will likely
cause problems within the complex terrain as funneling effects
tend to exacerbate any convective threat in the state. This threat
extends into far Southwest PA with focus around the periphery of
an advancing MCV currently migrating through Southern OH.

Kleebauer

..Previous Discussion..
Per collaboration with WFOs CTP, PHI, and LWX, we have included a
Moderate Risk to the Day 1 ERO across parts of the northern Mid
Atlantic Region to include NoVa and the DC-Balt metro regions,
northern DE and into southeast PA.

Longwave upper trough over the Upper Great Lakes/Midwest early
this morning will pivot eastward Tue-Tue night, pushing east of the Appalachians Wed morning. Embedded within the longwave trough is a
shortwave, currently along the IA/IL/MO tri- state area, which
will track across the OH Valley later this afternoon and across the
Mid Atlantic later this evening and overnight. This shortwave
should enhance the broad- scale across the Mid Atlantic region
(especially), while low-level frontogenesis also gets a boost south
of the 90-100kt upper jet streak in the lee of the large-scale
trough.

0-6km bulk shear values increasing to 25+ kts within the inherited
broad Slight Risk area (30-40+ knots over the northern Mid Atlantic
into the Northeast) will support the formation of
widespread/multi-cluster line segments ahead of the upper
trough/surface cold front during peak diurnal instability hours
this afternoon into the evening. MUCAPEs peak between 2000-3000
J/Kg, while TPWs remain around 2 standard deviations above normal
for early July (between 2.00-2.25" within the non-convective
environment across much of the Mid Atlantic into southern New
England). The concern over the Slight and especially Moderate Risk
areas will be with upwind propagation and cell training, as the
pre-frontal southwesterly low-level flow (20-25 kts at 850 mb
becomes nearly parallel and of similar magnitude as the mean
850-300 mb flow. 00Z HREF and RRFS probabilities of 24hr QPF
exceeding 3" climb above 60% within much of the Moderate Risk
area (highest with the RRFS), while probs exceeding 5" within the
24hr period reach 40-60% in spots per the RRFS (though 20-25% tops
per the HREF). Given the favorable thermodynamic profile (high
CAPE/PW environment) along with the broad-scale forcing, anticipate
areas of 2 to 3+ inch/hr rainfall rates this afternoon and evening.

The Moderate Risk area also encompasses areas recently hit by
heavier rainfall, evidenced by the lower FFGs (in some areas, 1 hr
FFGs 1.00" or less). This includes areas SE PA including the Middletown/Lancaster/Lebanon/Redding areas that received 4-7" of
rain on Monday.

Hurley

...West Texas into New Mexico...

16Z Update: The current SLGT risk was generally maintained with
only a minor expansion to the east to include more of the Western
Rolling Plains adjacent to the Concho Valley. Quasi-stationary
front will be the focal point later this afternoon and evening with
typical diurnal heat flux providing greater buoyancy with the
regional environment allowing for several thunderstorms to develop
in proxy to the boundary. 12z KMAF sounding was right up against
the daily record for PWATs and well beyond the 90th percentile for
the date meaning the environment is ripe for locally heavy precip
potential once the convective regime initiates. 12z HREF probs are
robust for both the neighborhood >2" indicator and the >1" EAS
field which notes a "bullseye" of up to 50% located over parts
of the Upper Trans Pecos into the adjacent Guadalupe Mtns. The
other area of concern will lie within that quasi-stationary front
with a elevated signature for >2" situated from the NM/TX border,
east across the Northern Permian Basin. Enhanced hourly rates will
be the primary threat for the period with 1-2"/hr rates very likely
in any strong convective cores. Look for scattered flash flood
signals within the above zones with the greatest threat positioned
over Southeast NM and adjacent TX Caprock as noted in the QPF/prob
fields.

Kleebauer

..Previous Discussion..

Farther south/west along the stalled frontal boundary...convection
is expected to be develop within a region of decent CAPE and
precipitable water values in excess of 2 standard deviations above
climatology. This area will also benefit from weak upper level
vorticity/shear axis within the broad-scale ridge, with tropical
moisture feeding in per the low-mid layer southeasterly flow.
850-700 mb moisture transport is pretty solid across the outlook
areas, but especially within the Slight Risk region across parts of
West TX into southeast NM where the 850-700 mb moisture flux
standardized anomalies peak between 3-4 standard deviations above
normal per the 00Z SREF and GEFS. Given the relatively healthy
low-level flow compared to the overall weaker mean flow, areas of
heavy, possibly excessive rainfall are anticipated, especially
within the Slight Risk area, considering the uptick in upwind
propagation and thus chances for cell training.

Hurley

...South Texas...

16Z Update: Only minor adjustments necessary for the SLGT risk
across Deep South TX as the previous forecast remains on track.
Little deviation in the prob fields from overnight allowed for a
continuation of the SLGT risk with emphasis on greatest threat
likely over the Lower RGV, including the cities of Brownsville and
McAllen.

Kleebauer

..Previous Discussion..

An influx of abnormally high TPW from the remnants of Tropical
Cyclone Barry (2.2 to 2.4", which is close to 3 standard
deviations above normal for early July) will combine with a
modestly unstable environment (MUCAPEs increasing to 1500-2500
J/Kg) in producing very heavy short-term rainfall rates later this afternoon/evening and potentially later into the overnight period.
Both the HREF and RRFS ensembles show high probabilities (>50%) of
3+ inch rainfall, with 30-40% probs of exceeding 5 inches.
Therefore expect more than a localized risk of flash flooding
(i.e. Slight vs Marginal) across portions of South Texas from
Corpus Christi south through Brownsville and the RGV.

Hurley


Day 2
Valid 12Z Wed Jul 02 2025 - 12Z Thu Jul 03 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS OF
SOUTHEAST VIRGINIA AND NORTHEAST NORTH CAROLINA, WESTERN FLORIDA
COAST, AND THE SOUTHWESTERN U.S...

...Lower Mid Atlantic and Southeast...

20Z Update: The combination of elevated moisture on the order of
+1 to +2 deviation PWATs, relevant buoyancy, modest shear, and the
progression of a cold front from the northwest will aid in
sufficient convergence in-of the VA Tidewater down through Eastern
NC on Wednesday. PWATs encroaching 2.2-2.4" across the above region
will setup an environment capable of not only heavy rainfall, but
efficient warm rain processes that should maximize QPF in any
convective cores that materialize. 12z CAMs continue to depict
forecast soundings over the Southeast Mid Atlantic coast that
exhibit textbook tall, skinny CAPE signatures with a deep moisture
layer sampled from the surface to tropopause. 12z HREF neighborhood
probs for >3" were running between 70-90% over the area extending
from Williamsburg, VA down through Morehead City, NC with >5"
probs hovering between 25-40% with a bullseye of 50-60% over the
Hampton Roads area of Southeast VA. These signals are indicative of
locally heavy rainfall likely with an areal average of 1-2", at
the very least within the ensemble means. This allowed for a
general maintenance of the SLGT risk inherited with some minor
expansions to cover for the latest HREF blended mean QPF footprint.

Scattered heavy convection will also be forecast away from the
above area with the main threat likely more urbanized flash flood
concerns within any heavier cells as the environment is ripe for
locally heavy rainfall from the Central Gulf coast to points north
and northeast.

...Southwest...

20Z Update: Synoptic progression across the Southwestern CONUS
coupled with a deep, moist advection pattern further inland from
the southeast will lead to widespread convective development across
West TX, extending westward through the terrain of NM and AZ. A
stagnant upper trough/ULL centered off the CA coast will meander
over the next 24 hrs to the east before finally pushing further
inland and opening up into quite a prolific trough providing large
scale ascent to much of the Desert Southwest east of the Colorado
river basin. Presence of monsoonal moisture will be amplified
moving into Wednesday as the amplified flow from the approaching
trough and ridge positioning over the Four Corners will create the
textbook funneling affect of deeper moisture poleward through West
TX to points north and northwest. The highest PWAT anomalies will
be centered over Southeast NM, Southern NM, and the Mogollon Rim
creating a generally buoyant environment over the aforementioned
areas. With MUCAPE between 1000-2500 J/kg and PWAT anomalies ~2
deviations above normal as depicted via the ECENS and NAEFS
outputs, expectation is for scattered heavy convective cores
capable of hourly rates approaching 1"/hr with generally slow cell
motions leading to some training concerns across the terrain. 12z
HREF 24hr ARI exceedance probabilities are between 40-70% for
exceeding 10yr intervals and 10-30% for even some 100yr ARI
threats, a testament to the expected magnitude of precip falling
during the period. Locally 1-2" of rainfall within the area is
plenty to cause significant flash flood issues in any one area
across the Sacramento's through the terrain west and northwest.

There is enough evidence given the expected environment and
widespread convective regime for a broad SLGT risk positioned
across El Paso, Southern NM, Southeast AZ, and the Mogollon Rim
across Central AZ.

...Western Florida Coast...

20Z Update: The combination of a slow-moving frontal progression
and potential for weak surface reflection over the Eastern Gulf
will create a period of unsettled weather in-of the Western FL
Peninsula. The prospects for heavy rainfall capable of widespread
flash flood concerns is still on the lower end with the best threat
relegated to the urban zones along the coast with the best threat
likely over western Pasco and Hillsborough counties, along with
Pinellas county where the Tampa metro is the center of where the
threat lies. When assessing the hi-res guidance today, you would
think there's a chance of 10+ inches of rainfall along the coast,
but a lot of that precip stems from the CAMs struggling with the
surface reflection and likely enhancing the baroclinicity along the
front, an issue that has cropped up in the past. Other
deterministic members within the global suite are closer to 4-7"
for maxima with ensemble depiction closer to the lower end of the
range. This is subjective to a multitude of factors ranging from
frontal positioning, surface convergence, location of the low
proxy, and other finer mesoscale details. At the current look, the
threat is still within the threshold of higher risk, but low to
medium confidence considering some of the finer details. At this
juncture, with the PWATs and focal point necessary for locally
enhanced rainfall potential with rates pushing 3-5"/hr in stronger
cells in any location, and the urbanization concerns where the
heaviest rain will fall, a SLGT risk was added to the three
counties inferred above with the Tampa/Clearwater/St. Petersburg
metro the area of greatest concern. Will be a period to monitor for
shifts in the risk level, whether downgrade or upgrade.

Kleebauer


Day 3
Valid 12Z Thu Jul 03 2025 - 12Z Fri Jul 04 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS WESTERN
PORTIONS OF THE FLORIDA PENINSULA...

...Florida and Georgia...

20Z Update: Little changes was necessary for the SLGT risk across
the western FL coast as the previous forecast remains on track.
This period has the best consistency in the positioning and
magnitude of the heavy precip threat among the deterministic. As of
now, the risk is lower in terms of magnitude compared to what could
transpire in the D2, so the threat could be downgraded if the
previous periods doesn't materialize. However, overlap if the
threat D2 transpires would ultimately create a greater threat, so
some of the threat could be contingent on the evolution. ML is
consistent in its interpretation of the heavier rain positioned
between Clearwater down to Ft. Myers, so it's worth noting we have
a good signal for the location. It will be worth monitoring in the
coming days with plenty of time for any adjustments.

Kleebauer

..Previous Discussion..

Subtle changes were made to the Slight and Marginal Risk areas
inherited from yesterday's Day 4 ERO. Southern periphery of the
longwave upper trough crosses the area Thu-Thu night, with the
guidance showing embedded shortwaves (possibly convectively-
enhanced) reaching South FL toward the end of the period (12Z Fri).
Ahead of the nearly stationary surface front, onshore west to
southwest low-level inflow from the eastern Gulf will likely lead
to a more focused area of low-level moisture transport/flux
convergence over much of the west coast of FL, especially north of
Ft. Myers to include the Tampa-St. Pete area, where 0-6km bulk
shear values do approach 25 kts (allowing for more
organized/widespread convective clusters). The RRFS is most
particularly robust with the QPF within the Slight Risk area (areas
of 3-6+ inches), which considering the thermodynamic
environment/deep subtropical moisture (TPW values 2.25 to 2.50"),
is certainly plausible. Especially considering the onshore low-
level inflow will likely exceed (perhaps double) the mean 850-300
mb wind), enhancing the potential for cell training. Even with a
more limited (tall/skinny) CAPE profile, sub-hourly rainfall rates
of 2.5-3.0+ inches within this environment will be possible,
especially within the Slight Risk area.

Hurley

...Southern Plains to Southwest...

Continued deep moist advective pattern will lead to scattered or
even widespread thunderstorm activity over much of West TX up
through the Central Rockies as the upstream synoptic evolution of
the ejecting trough will create a pretty robust large scale ascent
signature across much of the CONUS west of the 100W marker. Still
some discrepancy on the eastern expansion of the heavier convective
threat with some guidance inferring the Concho Valley, others the
Permian Basin and Trans Pecos, and others as far west as Southwest
TX. Too much spread in the deterministic with the ensemble means
relatively modest in magnitude. As we move into CAMs range, expect
the signal to ramp up in the magnitude with a more defined axis of
heavy precip likely to allow for a targeted SLGT risk. Areas within
the Central Rockies will be evaluated in the coming days as well
with the core of the shortwave energy ejecting out of the
Southwest likely to motion overhead. This could be a target for
heavy rain prospects along the Southern Laramie Range down through
the Foothills of CO Rockies with some guidance depicting 2-3" of
rainfall in the period, something that could also spur an upgrade
in the risk with the environment in place. For now, a broad MRGL
risk encompasses much of the Southwest, Southern Plains, and
Central Rockies.

Kleebauer


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!-CVschpVgrP2UiTQpn8tRQ98TJ43UGCHyvwAJfQFCkY3= 0QvmIZTQoepv7ovBcC2Ew9cBJG_kshNu-a-G7uYmhKJ7Jsk$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!-CVschpVgrP2UiTQpn8tRQ98TJ43UGCHyvwAJfQFCkY3= 0QvmIZTQoepv7ovBcC2Ew9cBJG_kshNu-a-G7uYmEvvFIU4$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!-CVschpVgrP2UiTQpn8tRQ98TJ43UGCHyvwAJfQFCkY3= 0QvmIZTQoepv7ovBcC2Ew9cBJG_kshNu-a-G7uYmIBRlPbU$=20

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FOUS30 KWBC 020810
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
410 AM EDT Wed Jul 2 2025

Day 1
Valid 12Z Wed Jul 02 2025 - 12Z Thu Jul 03 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS OF
SOUTHEAST VIRGINIA AND NORTHEAST NORTH CAROLINA, WESTERN FLORIDA=20
PENINSULA, AND THE SOUTHWESTERN U.S...

...Lower Mid Atlantic and Southeast...

Longwave upper trough and embedded shortwave energy will push
slowly eastward today, finally pushing off the Mid Atlantic coast
this evening. At the surface, the associated cold front will too
exhibit gradual eastward progression, likely not pushing off the
coast until sometime Thursday. The very favorable deep-layer
thermodynamic environment ahead of the upper trough/surface front
will be characterized by PWATs between 2.2-2.4" (~2 standard
deviations above normal) along with MUCAPEs of 1000-2000 J/Kg.
Based on the 00Z guidance and trends, only minor adjustments were
made to the Slight Risk area across eastern NC and southeast VA.=20
00Z HREF neighborhood probs for >3" were still running between=20
70-90% over the Slight Risk area, with >5" probs peaking between
40-50%.=20

Scattered heavy convection will also be forecast away from the=20
above area with the main threat likely more urbanized flash flood=20
concerns within any heavier cells as the environment is ripe for=20
locally heavy rainfall from the Central Gulf coast to points north=20
and northeast.

...Southwest...

Modest eastward expansion across southeast NM and West TX was made
to the Slight Risk area inherited from yesterday's Day 2 ERO. This
based on the latest guidance trends; not just with the bump in=20
deterministic QPF (especially ensemble of CAMs), but also with the=20
rise in QPF exceedance probabilities per both latest HREF and RRFS.
Synoptic progression across the Southwestern CONUS coupled with a=20
deep, moist advection pattern further inland from the southeast=20
will lead to widespread convective development across West TX,=20
extending westward through the terrain of NM and AZ. A stagnant=20
upper trough/ULL slowly migrate across far southern CA later today=20
and Wed night. This will push the region of favorable upper level=20 diffluence/large scale ascent to much of the Desert Southwest east=20
of the Colorado river basin. Presence of monsoonal moisture will be
amplified moving into Wednesday as the amplified flow from the=20
approaching trough and ridge positioning over the Four Corners will
create the textbook funneling affect of deeper moisture poleward=20
through West TX to points north and northwest.=20

PWAT anomalies between 2-3 standard deviations above normal are
again noted across West TX into southern and central NM-AZ, which
with MUCAPEs between 1000-2000+ J/Kg, will create a generally=20
buoyant environment over the aforementioned areas. The expectation
is for scattered heavy convective cores capable of hourly rates=20
approaching 1"/hr with generally slow cell motions leading to some=20
training concerns across the terrain. 00Z HREF 24hr ARI exceedance probabilities for exceeding 10yr intervals peak between 40-70%
across southern MN, with even spotty 10-30% probs of exceeding
the 100yr ARI, a testament to the expected magnitude of precip=20
falling during the period. Locally 2-3+" of rainfall within the=20
area is plenty to cause significant flash flood issues in any one=20
area across the Sacramento's through the terrain west and=20
northwest.

...Western Florida Coast...

Based on the 00Z guidance/trends, have expanded the Slight Risk
area a bit southward along the west coast of FL, towards the Punta
Gorda area. The combination of a slow-moving frontal progression=20
and potential for weak surface reflection over the Eastern Gulf=20
will create a period of unsettled weather in-of the Western FL=20
Peninsula. The prospects for heavy rainfall capable of widespread=20
flash flood concerns is still on the lower end with the best threat
relegated to the urban zones along the coast with the best threat=20
likely over western Pasco and Hillsborough counties, along with=20
Pinellas county where the Tampa metro is the center of where the=20
threat lies.=20

Based on the latest HREF 24hr QPF probabilities -- i.e. widespread
70-90%+ probs of at least 3 inches, pocket of 50-70% of at least=20
5" along the coast from Tampa Bay northward, and a small area of=20
35-30% probs of exceeding 8" -- anticipate widespread 3-5" within
the Slight Risk area with localized totals of 8+ inches. 2.2-2.4"+
PWATs along with a destabilized airmass off the Gulf will generate
highly efficient short term rainfall rates, likely pushing 3+
inch/hr within the stronger cells.=20

Hurley/Kleebauer


Day 2
Valid 12Z Thu Jul 03 2025 - 12Z Fri Jul 04 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS WESTERN=20
PORTIONS OF THE FLORIDA PENINSULA...

...Florida and Georgia...

Subtle changes were made to the Slight and Marginal Risk areas=20
inherited from yesterday's Day 3 ERO. Southern periphery of the=20
longwave upper trough crosses the area Thu-Thu night, with the=20
guidance showing embedded shortwaves (possibly convectively-=20
enhanced) reaching South FL toward the end of the period (Thursday
night). Ahead of the nearly stationary surface front, onshore west
to southwest low-level inflow from the eastern Gulf will likely=20
lead to a more focused area of low-level moisture transport/flux=20
convergence over much of the west coast of FL, especially north of=20
Ft. Myers to include the Tampa-St. Pete area, where 0-6km bulk=20
shear values do approach 25 kts (allowing for more=20
organized/widespread convective clusters). The RRFS is most=20
particularly robust with the QPF within the Slight Risk area (areas
of 3-6+ inches), which considering the thermodynamic=20
environment/deep subtropical moisture (TPW values 2.25 to 2.50"),=20
is certainly plausible. Especially considering the onshore low-=20
level inflow will likely exceed (perhaps double) the mean 850-300=20
mb wind), enhancing the potential for cell training. Even with a=20
more limited (tall/skinny) CAPE profile, sub-hourly rainfall rates
again of of 2.5-3.0+ inches within this environment will be=20
possible underneath the strongest cells, especially within the=20
Slight Risk area.

...Southern Plains to Southwest...

Continued deep moist advective pattern will lead to scattered or
even widespread thunderstorm activity over much of West TX up
through the Central Rockies as the upstream synoptic evolution of
the ejecting trough will create a pretty robust large scale ascent
signature across much of the CONUS west of the 100W marker. Still
some discrepancy on the eastern expansion of the heavier convective
threat with some guidance inferring the Concho Valley, others the
Permian Basin and Trans Pecos, and others as far west as Southwest
TX. Too much spread in the deterministic with the ensemble means
relatively modest in magnitude. As we move into CAMs range, expect
the signal to ramp up in the magnitude with a more defined axis of
heavy precip likely to allow for a targeted SLGT risk. Areas within
the Central Rockies will be evaluated in the coming days as well
with the core of the shortwave energy ejecting out of the
Southwest likely to motion overhead. This could be a target for
heavy rain prospects along the Southern Laramie Range down through
the Foothills of CO Rockies with some guidance depicting 2-3" of
rainfall in the period, something that could also spur an upgrade
in the risk with the environment in place. For now, a broad MRGL
risk encompasses much of the Southwest, Southern Plains, and
Central Rockies.

Hurley/Kleebauer


Day 3
Valid 12Z Fri Jul 04 2025 - 12Z Sat Jul 05 2025

...THERE ARE MARGINAL RISKS OF EXCESSIVE RAINFALL ACROSS PARTS OF
THE NORTHERN ROCKIES, NORTHERN AND CENTRAL PLAINS, UPPER=20
MISSISSIPPI VALLEY, AND THE FLORIDA PENINSULA...

...Florida Peninsula...

Lingering upper level shortwave energy along with a surface
reflection (surface low along west coast and associated frontal=20
boundaries) will again maintain a favorable environment for more
organized (widespread) convection, particularly during peak=20
diurnal heating. Not surprising given the lead time (day 3=20
forecast), spread with the current model QPFs is fairly high. As a=20
result, have maintained the Marginal Risk area inherited from=20
yesterday's Day 4 ERO, as the favorable thermodynamic environment=20
will support at least localized instances of flash flooding per the
isolated 24hr maxima of 4-7+ inches per the 00Z Regional GEM and=20
RRFS.=20

...Idaho into Montana and Northwest Wyoming...

Have hoisted a fairly broad Marginal Risk area across much of ID=20
and MT along with northwest WY based on the converging guidance=20
trends (QPF especially). Models show the longwave upper trough and=20
embedded shortwave energy becoming more negatively tilted as the=20
trough pivots across the Northwestern CONUS. Robust QG forcing is=20
noted as a result, with the deep-layer lift coinciding with a=20
favorable thermodynamic environment (PWATs 1-2 standard deviations=20
above normal and MUCAPEs ~500-1000 J/Kg would favor areas of=20
locally heavy rainfall, up to 3-4" per the CMC and 1.5-3" per the=20
ECMWF, GFS, and NAM. Given the terrain considerations and flashy=20
runoff and streamflow response within this region, have for now=20
hoisted a Marginal Risk area in anticipation of an isolated flash=20
flood threat.


...Eastern Portions of the Missouri Valley into the Upper
Midwest...

Expanded the Marginal Risk area from yesterday's Day 4 ERO to
include parts of eastern NE and northern KS. Deep-layer QG forcing
becomes more favorable by late Fri as the upper trough axis pushes
east. Meanwhile, SSW to SW LLJ will increase to 30-40 kts at 850 mb
Fri night, aligning parallel to and approaching the same magnitude
of the mean 850-300 mb wind. This results in a diminishment of the
Corfidi Vectors by Fri night, eventually becoming northerly and=20
opposing the low-level inflow. Given the degree of upwind
propagation expected, cell mergers and training will become more
likely by Fri night ahead of the approaching surface boundary.
However, the big uncertainty will be the degree of elevated deep-
layer destabilization, as at least for now much of the global
guidance is not overly bullish (MUCAPEs generally <1000 J/Kg north
of KS-southern NE). Given this along with the considerable spread=20
in model QPFs, for now have maintained a Marginal Risk ERO.=20

Hurley

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!9I4yVEf5ywlibSh9S-6idlpA_-QrBCy_Upq_qhXRiJs3= 6uy_zMkxbjOJyLmo3xx4Wy4XGFaFutPUkvhZ7TZsYq5Lmqc$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!9I4yVEf5ywlibSh9S-6idlpA_-QrBCy_Upq_qhXRiJs3= 6uy_zMkxbjOJyLmo3xx4Wy4XGFaFutPUkvhZ7TZsR5gaipY$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!9I4yVEf5ywlibSh9S-6idlpA_-QrBCy_Upq_qhXRiJs3= 6uy_zMkxbjOJyLmo3xx4Wy4XGFaFutPUkvhZ7TZsq-6zWQg$=20

=3D =3D =3D
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FOUS30 KWBC 021240
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
840 AM EDT Wed Jul 2 2025

Day 1
Valid 1236Z Wed Jul 02 2025 - 12Z Thu Jul 03 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS OF
SOUTHEAST VIRGINIA AND NORTHEAST NORTH CAROLINA, WESTERN FLORIDA
PENINSULA, AND THE SOUTHWESTERN U.S...

1240Z Update: Models are struggling to handle the vast expanse of
convection following the eastern flank of the ULL progression off
the CA coast. Scattered showers/thunderstorms will continue on a
south to north progression with some training within the confines
of Southeastern CA up through the Southern third of NV leading to
isolated flash flood concerns over the region. The previous MRGL
was expanded further west to account for the threat this morning
and afternoon. For more information on this setup, please see MPD
#0571.=20

Kleebauer

...Lower Mid Atlantic and Southeast...

Longwave upper trough and embedded shortwave energy will push
slowly eastward today, finally pushing off the Mid Atlantic coast
this evening. At the surface, the associated cold front will too
exhibit gradual eastward progression, likely not pushing off the
coast until sometime Thursday. The very favorable deep-layer
thermodynamic environment ahead of the upper trough/surface front
will be characterized by PWATs between 2.2-2.4" (~2 standard
deviations above normal) along with MUCAPEs of 1000-2000 J/Kg.
Based on the 00Z guidance and trends, only minor adjustments were
made to the Slight Risk area across eastern NC and southeast VA.
00Z HREF neighborhood probs for >3" were still running between
70-90% over the Slight Risk area, with >5" probs peaking between
40-50%.

Scattered heavy convection will also be forecast away from the
above area with the main threat likely more urbanized flash flood
concerns within any heavier cells as the environment is ripe for
locally heavy rainfall from the Central Gulf coast to points north
and northeast.

...Southwest...

Modest eastward expansion across southeast NM and West TX was made
to the Slight Risk area inherited from yesterday's Day 2 ERO. This
based on the latest guidance trends; not just with the bump in
deterministic QPF (especially ensemble of CAMs), but also with the
rise in QPF exceedance probabilities per both latest HREF and RRFS.
Synoptic progression across the Southwestern CONUS coupled with a
deep, moist advection pattern further inland from the southeast
will lead to widespread convective development across West TX,
extending westward through the terrain of NM and AZ. A stagnant
upper trough/ULL slowly migrate across far southern CA later today
and Wed night. This will push the region of favorable upper level diffluence/large scale ascent to much of the Desert Southwest east
of the Colorado river basin. Presence of monsoonal moisture will be
amplified moving into Wednesday as the amplified flow from the
approaching trough and ridge positioning over the Four Corners will
create the textbook funneling affect of deeper moisture poleward
through West TX to points north and northwest.

PWAT anomalies between 2-3 standard deviations above normal are
again noted across West TX into southern and central NM-AZ, which
with MUCAPEs between 1000-2000+ J/Kg, will create a generally
buoyant environment over the aforementioned areas. The expectation
is for scattered heavy convective cores capable of hourly rates
approaching 1"/hr with generally slow cell motions leading to some
training concerns across the terrain. 00Z HREF 24hr ARI exceedance probabilities for exceeding 10yr intervals peak between 40-70%
across southern MN, with even spotty 10-30% probs of exceeding
the 100yr ARI, a testament to the expected magnitude of precip
falling during the period. Locally 2-3+" of rainfall within the
area is plenty to cause significant flash flood issues in any one
area across the Sacramento's through the terrain west and
northwest.

...Western Florida Coast...

Based on the 00Z guidance/trends, have expanded the Slight Risk
area a bit southward along the west coast of FL, towards the Punta
Gorda area. The combination of a slow-moving frontal progression
and potential for weak surface reflection over the Eastern Gulf
will create a period of unsettled weather in-of the Western FL
Peninsula. The prospects for heavy rainfall capable of widespread
flash flood concerns is still on the lower end with the best threat
relegated to the urban zones along the coast with the best threat
likely over western Pasco and Hillsborough counties, along with
Pinellas county where the Tampa metro is the center of where the
threat lies.

Based on the latest HREF 24hr QPF probabilities -- i.e. widespread
70-90%+ probs of at least 3 inches, pocket of 50-70% of at least
5" along the coast from Tampa Bay northward, and a small area of
35-30% probs of exceeding 8" -- anticipate widespread 3-5" within
the Slight Risk area with localized totals of 8+ inches. 2.2-2.4"+
PWATs along with a destabilized airmass off the Gulf will generate
highly efficient short term rainfall rates, likely pushing 3+
inch/hr within the stronger cells.

Hurley/Kleebauer


Day 2
Valid 12Z Thu Jul 03 2025 - 12Z Fri Jul 04 2025

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS WESTERN
PORTIONS OF THE FLORIDA PENINSULA...

...Florida and Georgia...

Subtle changes were made to the Slight and Marginal Risk areas
inherited from yesterday's Day 3 ERO. Southern periphery of the
longwave upper trough crosses the area Thu-Thu night, with the
guidance showing embedded shortwaves (possibly convectively-
enhanced) reaching South FL toward the end of the period (Thursday
night). Ahead of the nearly stationary surface front, onshore west
to southwest low-level inflow from the eastern Gulf will likely
lead to a more focused area of low-level moisture transport/flux
convergence over much of the west coast of FL, especially north of
Ft. Myers to include the Tampa-St. Pete area, where 0-6km bulk
shear values do approach 25 kts (allowing for more
organized/widespread convective clusters). The RRFS is most
particularly robust with the QPF within the Slight Risk area (areas
of 3-6+ inches), which considering the thermodynamic
environment/deep subtropical moisture (TPW values 2.25 to 2.50"),
is certainly plausible. Especially considering the onshore low-
level inflow will likely exceed (perhaps double) the mean 850-300
mb wind), enhancing the potential for cell training. Even with a
more limited (tall/skinny) CAPE profile, sub-hourly rainfall rates
again of of 2.5-3.0+ inches within this environment will be
possible underneath the strongest cells, especially within the
Slight Risk area.

...Southern Plains to Southwest...

Continued deep moist advective pattern will lead to scattered or
even widespread thunderstorm activity over much of West TX up
through the Central Rockies as the upstream synoptic evolution of
the ejecting trough will create a pretty robust large scale ascent
signature across much of the CONUS west of the 100W marker. Still
some discrepancy on the eastern expansion of the heavier convective
threat with some guidance inferring the Concho Valley, others the
Permian Basin and Trans Pecos, and others as far west as Southwest
TX. Too much spread in the deterministic with the ensemble means
relatively modest in magnitude. As we move into CAMs range, expect
the signal to ramp up in the magnitude with a more defined axis of
heavy precip likely to allow for a targeted SLGT risk. Areas within
the Central Rockies will be evaluated in the coming days as well
with the core of the shortwave energy ejecting out of the
Southwest likely to motion overhead. This could be a target for
heavy rain prospects along the Southern Laramie Range down through
the Foothills of CO Rockies with some guidance depicting 2-3" of
rainfall in the period, something that could also spur an upgrade
in the risk with the environment in place. For now, a broad MRGL
risk encompasses much of the Southwest, Southern Plains, and
Central Rockies.

Hurley/Kleebauer


Day 3
Valid 12Z Fri Jul 04 2025 - 12Z Sat Jul 05 2025

...THERE ARE MARGINAL RISKS OF EXCESSIVE RAINFALL ACROSS PARTS OF
THE NORTHERN ROCKIES, NORTHERN AND CENTRAL PLAINS, UPPER
MISSISSIPPI VALLEY, AND THE FLORIDA PENINSULA...

...Florida Peninsula...

Lingering upper level shortwave energy along with a surface
reflection (surface low along west coast and associated frontal
boundaries) will again maintain a favorable environment for more
organized (widespread) convection, particularly during peak
diurnal heating. Not surprising given the lead time (day 3
forecast), spread with the current model QPFs is fairly high. As a
result, have maintained the Marginal Risk area inherited from
yesterday's Day 4 ERO, as the favorable thermodynamic environment
will support at least localized instances of flash flooding per the
isolated 24hr maxima of 4-7+ inches per the 00Z Regional GEM and
RRFS.

...Idaho into Montana and Northwest Wyoming...

Have hoisted a fairly broad Marginal Risk area across much of ID
and MT along with northwest WY based on the converging guidance
trends (QPF especially). Models show the longwave upper trough and
embedded shortwave energy becoming more negatively tilted as the
trough pivots across the Northwestern CONUS. Robust QG forcing is
noted as a result, with the deep-layer lift coinciding with a
favorable thermodynamic environment (PWATs 1-2 standard deviations
above normal and MUCAPEs ~500-1000 J/Kg would favor areas of
locally heavy rainfall, up to 3-4" per the CMC and 1.5-3" per the
ECMWF, GFS, and NAM. Given the terrain considerations and flashy
runoff and streamflow response within this region, have for now
hoisted a Marginal Risk area in anticipation of an isolated flash
flood threat.


...Eastern Portions of the Missouri Valley into the Upper
Midwest...

Expanded the Marginal Risk area from yesterday's Day 4 ERO to
include parts of eastern NE and northern KS. Deep-layer QG forcing
becomes more favorable by late Fri as the upper trough axis pushes
east. Meanwhile, SSW to SW LLJ will increase to 30-40 kts at 850 mb
Fri night, aligning parallel to and approaching the same magnitude
of the mean 850-300 mb wind. This results in a diminishment of the
Corfidi Vectors by Fri night, eventually becoming northerly and
opposing the low-level inflow. Given the degree of upwind
propagation expected, cell mergers and training will become more
likely by Fri night ahead of the approaching surface boundary.
However, the big uncertainty will be the degree of elevated deep-
layer destabilization, as at least for now much of the global
guidance is not overly bullish (MUCAPEs generally <1000 J/Kg north
of KS-southern NE). Given this along with the considerable spread
in model QPFs, for now have maintained a Marginal Risk ERO.

Hurley

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!5Kn62oG8RNL3npuJ1WNzJH-rTZtBrXSZVACzlO6-18yw= AUY73I7mKoKZzz-0RX2UyU77W0KdIdPyxKHOGZY8Hz8gNsc$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!5Kn62oG8RNL3npuJ1WNzJH-rTZtBrXSZVACzlO6-18yw= AUY73I7mKoKZzz-0RX2UyU77W0KdIdPyxKHOGZY8ezJlBeQ$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!5Kn62oG8RNL3npuJ1WNzJH-rTZtBrXSZVACzlO6-18yw= AUY73I7mKoKZzz-0RX2UyU77W0KdIdPyxKHOGZY8de2eHoI$=20

=3D =3D =3D
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