Forum: crisis/line

DAY3SVR: Nws Storm Prediction Center Norman Ok

From COD Weather Processor @1:2320/107 to All on Tue Sep 1 19:31:12 2026

ACUS03 KWNS 011931
SWODY3
SPC AC 011930

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0230 PM CDT Tue Sep 01 2026

Valid 031200Z - 041200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE UPPER
OHIO VALLEY TO MID-ATLANTIC COAST...

...SUMMARY...
At least widely scattered severe storms, accompanied by damaging
gusts and perhaps some large hail, appear likely across portions of
the Ohio Valley to the Mid-Atlantic coast on Thursday. More isolated
severe storms capable of large hail and damaging winds appear
possible over the North Dakota-Minnesota Red River Valley into the
upper Midwest Thursday afternoon into night.

...Synopsis...

Broader-scale troughing is forecast over the western CONUS with
low-amplitude ridging from the upper MS Valley and upper Great Lakes
into the Southeast. Between the ridge and an upper low over QC,
latest model guidance indicates the progression of a short-wave
trough and associated 40-50 kt jet streak from the lower Great Lakes
through the Mid-Atlantic and portions of New England. Other more
subtle disturbances are depicted within the periphery of the ridge
over the Great Lakes into the upper MS Valley.

At the surface, an area of low pressure is forecast over the Dakotas
on Thursday with an associated warm front slowly lifting north
through the upper MS Valley and upper Midwest. The boundary is
expected to stretch east through the Great Lakes into the
Mid-Atlantic with the specific location of the boundary dictated by
the extent of thunderstorm activity and associated convective
outflow Wednesday night into Thursday morning.

...Great Lakes and Ohio Valley to Mid-Atlantic Coast...

One or multiple thunderstorm complexes may be ongoing Thursday
morning from the Great Lakes through the Northeast, aided by forcing
for ascent attendant to the previously mentioned mid-level
disturbances. The presence of the early-day storms leads to
uncertainty in the extent of air mass overturning that occurs, and
where the strongest instability will develop by afternoon. As such,
the Marginal Risk probability envelope has been broadened slightly
over the Mid-Atlantic with the Slight Risk probabilities remaining
unchanged.

The overlap of 30-40+ kt of deep-layer shear with a moist and
potentially moderately to strongly unstable warm sector will
conditionally support supercell and bowing storm modes with an
attendant risk for damaging wind gusts and large hail from Thursday
afternoon into evening.

...North Dakota-Minnesota Red River Valley into the upper Midwest...

A plume of steep mid-level lapse rates/EML is forecast to overly a
moist boundary layer, yielding a moderately to strongly unstable air
mass by afternoon in the vicinity of the warm front. The instability
will coincide with up to 40-50 kt of deep-layer shear, conditionally
yielding a very favorable severe storm environment. However, capping
concerns and the timing of any weak disturbances cresting the ridge
axis limit predictability, with only an areal increase in the
Marginal Risk probabilities included in this forecast. A categorical
upgrade to a level 2/Slight Risk may become necessary in subsequent
forecasts.

..Mead.. 09/01/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Wed Sep 2 07:29:24 2026

ACUS03 KWNS 020729
SWODY3
SPC AC 020728

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0228 AM CDT Wed Sep 02 2026

Valid 041200Z - 051200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF
THE MID ATLANTIC...

...SUMMARY...
Scattered severe thunderstorms, mainly producing damaging gusts, are
expected across portions of the southern Mid-Atlantic on Friday.
More isolated severe storms (with wind and hail) may occur over
parts of the Midwest.

...Synopsis...
Upper ridging will continue over the central and eastern U.S., with
upper troughs meandering over the Interior West and the Northeast. A
broad warm frontal boundary will be draped from parts of the Midwest
to the Atlantic coastline, overspread by deep-layer northwesterly
flow. Multiple embedded impulses will traverse this northwest flow
regime, promoting the development of thunderstorm clusters in the
process.

...Southern portions of the Mid-Atlantic...
The best chance for scattered severe thunderstorms will be across
portions of southern WV to the NC shoreline on Friday. By afternoon, boundary-layer destabilization along a differential heating zone,
left behind by storms in preceding days, will promote renewed
thunderstorm development. Despite meager mid-level lapse rates, 70+
F surface dewpoints and warm temperatures exceeding 90 F will yield
widespread 2000-3000 J/kg MLCAPE. Given stronger northwesterly flow
aloft, 30+ kts of effective bulk (speed) shear will support
multicells and supercells capable of damaging gusts.

...Portions of the Midwest and OH Valley...
Rich low-level moisture along the warm front (i.e. 70s F dewpoints),
beneath 7-8 C/km mid-level lapse rates, will support 3000+ J/kg
MLCAPE and minimal convective inhibition. While upper support will
be quite subtle at best, strong heating and minimal capping may
support isolated thunderstorm development along the front. Only
Marginal Risk probabilities were introduced given the expected
sparse and brief nature of the severe threat. However, any storms
that mature and become sustained will be capable of producing severe
wind or hail.

..Squitieri.. 09/02/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Wed Sep 2 19:24:36 2026

ACUS03 KWNS 021919
SWODY3
SPC AC 021918

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0218 PM CDT Wed Sep 02 2026

Valid 041200Z - 051200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF
THE SOUTHERN MID-ATLANTIC...

...SUMMARY...
Widely scattered severe thunderstorms, mainly producing damaging
gusts, are expected across portions of the southern Mid-Atlantic on
Friday. More isolated severe storms capable of severe winds and
large hail may occur over parts of the Midwest Friday afternoon into
night.

...Synopsis...

A mid-level ridge over central North America will undergo further
amplification this period with that feature bracketed by troughs
over the western CONUS and eastern Canada into the Northeast. As has
been the case over the past several days, subtle disturbances
embedded within the broader-scale flow regime will serve as foci for thunderstorm development. At the surface, a lee cyclone will evolve
over the northern High Plains with an associated surface front
stretching from the northern Plains through the upper Midwest to the
southern Mid-Atlantic coast.

...Lower Ohio Valley into the southern Mid-Atlantic...

There is reasonably good agreement across the 12Z parameterized
models that scattered thunderstorms may be ongoing Friday morning
across portions of the OH Valley/southern Great Lakes region in
association with an embedded vorticity maximum. Whether that
convection persists into afternoon remains uncertain; however, it
does appear that the mid-level disturbance will progress into the
Mid-Atlantic in tandem with a belt of 35-40 kt west-northwest flow
in the mid levels. Forcing for ascent associated with that
disturbance will promote renewed thunderstorm development by
afternoon along the effective surface front and within a moderately
unstable air mass. Sufficient vertical shear will exist to support
organized storm modes with the predominant hazard being damaging
wind gusts.

This forecast update will include a slight northward expansion of
the Slight Risk probabilities based on 12Z guidance.

...Midwest/Corn Belt...

In the wake of possible early-day storms described in the previous
section, steep mid-level lapse rates within the eastern fringe of an elevated-mixed layer (EML) will coincide with a moist boundary layer
to yield a moderately to strongly unstable air mass by afternoon in
the vicinity of the surface front. The proximity to the building
mid-level ridge and resultant capping across the warm sector lead to considerable uncertainty in the extent and location of surface-based thunderstorm development Friday afternoon into night. While
deep-layer shear is forecast to be weaker than that expected on
Thursday, the degree of instability will conditionally support a
large hail and severe wind risk with any surface-based storms that
develop.

Marginal Risk probabilities will be maintained with this forecast
update due to the limited predictability in convective evolution.

..Mead.. 09/02/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Thu Sep 3 07:19:30 2026

ACUS03 KWNS 030719
SWODY3
SPC AC 030718

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0218 AM CDT Thu Sep 03 2026

Valid 051200Z - 061200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR NORTH CAROLINA
INTO NORTHERN SOUTH CAROLINA AND EXTREME EASTERN TENNESSEE...

...SUMMARY...
Severe thunderstorms producing scattered damaging gusts are possible
across portions of the southern Mid-Atlantic on Saturday. A couple
instances of severe wind/hail with isolated thunderstorms may also
occur across portions of the Ohio Valley.

...Synopsis...
An upper ridge will persevere across the Plains states, with upper
troughs remaining in place across the Interior West and East Coast.
Similar to Day 2, the best chance for severe thunderstorms will be
primarily constrained to the eastern CONUS, where subtle mid-level
impulses will overspread rich low-level moisture, contributing to
enough buoyancy and vertical wind shear to encourage damaging wind
production with the stronger storms.

...OH Valley to the Mid-Atlantic Coastline...
At least one mid-level impulse will traverse the OH Valley to NC
corridor on Saturday, perhaps accompanied by a morning cluster of thunderstorms. Regardless, the impulse is poised to reach the lee of
the Appalachians by Saturday afternoon, where upper 60s to lower 70s
F surface dewpoints await. By this time, boundary layer mixing will
encourage either the intensification of ongoing storms with the
approaching impulse, the development of new storms, or both, all
along a differential heating zone left behind by previous day's
storms. 2000-3000 J/kg MLCAPE will be in place, along with 30+ kts
of effective bulk shear driven by modest northwesterly flow aloft.
Multicells are the expected storm mode, with severe gusts and
perhaps an instance or two of hail.

Farther to the northwest, strong surface heating along an effective
warm front, characterized by mid 70s F surface dewpoints beneath 6.5
C/km mid-level lapse rates (hence 2500-4000 J/kg MLCAPE) will
encourage isolated thunderstorm development across portions of the
OH Valley. Vertical shear and ascent should be relatively weak, so
the severe threat should be sparse. Nonetheless, any storms that
mature and sustain themselves may pose a severe wind/hail threat.

..Squitieri.. 09/03/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Thu Sep 3 19:19:04 2026

ACUS03 KWNS 031918
SWODY3
SPC AC 031918

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0218 PM CDT Thu Sep 03 2026

Valid 051200Z - 061200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
SOUTHERN VIRGINIA...THE CAROLINAS...NORTHEAST TENNESSEE...AND FAR
SOUTHERN WEST VIRGINIA...

...SUMMARY...
Severe thunderstorms capable of damaging gusts are possible across
portions of the southern Mid-Atlantic and Carolinas on Saturday
afternoon and evening. Isolated occurrences of large hail and severe
wind gusts also appear possible over parts of the northern Plains
and vicinity Saturday afternoon into night.

...Synopsis...

A prominent, mid-level ridge will persist over the central U.S. with
troughs on either side, over the western CONUS and in the Northeast.
Similar to previous days, thunderstorm development will largely be
associated with subtle mid-level disturbances embedded within the
broader-scale pattern. One more notable perturbation is expected to
progress from the OH Valley into the southern Mid-Atlantic and
Carolinas on Saturday. At the surface, an area of low pressure is
forecast over the northern Plains with an attending boundary
extending through the Midwest to the southern Mid-Atlantic or
Carolinas.

...Ohio Valley into the southern Mid-Atlantic and Carolinas...

Latest model guidance is in good agreement in depicting a cluster of thunderstorms over portions of the Great Lakes into the OH Valley at
12Z Saturday, likely associated with the mid-level disturbance
mentioned above. It remains unclear whether any of the early-day
storms will persist into the afternoon. Those that do are likely to
intensify as they encounter a hot, moist, and moderately unstable
air mass present across portions of VA into the Carolinas.
Additional, in-situ storm development appears possible along the
primary front and lee trough. An increase in mid-level flow and
resultant deep-layer shear (up to 30-35 kt) is expected with the
arrival of the mid-level disturbance, suggesting the potential for
organized storm modes, with the primary hazard being damaging wind
gusts Saturday afternoon and evening.

...Northern Plains...

Moderate to strong instability is forecast Saturday afternoon in the
vicinity of the surface low and attending front. The close proximity
to the mid-level ridge leads to uncertainty in convective evolution
through the forecast period. However, a number of models, both
ensemble and deterministic, indicate storm development during the
peak of the diurnal heating cycle. Given the degree of instability
and ample deep-layer shear, a few severe storms appear possible with
the primary hazards being large hail and severe wind gusts.

..Mead.. 09/03/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Fri Sep 4 06:37:42 2026

ACUS03 KWNS 040637
SWODY3
SPC AC 040636

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0136 AM CDT Fri Sep 04 2026

Valid 061200Z - 071200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE SOUTHEAST...AND THE NORTHERN PLAINS...

...SUMMARY...
Strong wind gusts are possible across the Southeast Sunday afternoon
and early evening. A more uncertain and conditional risk for severe
wind and hail is expected across parts of the northern Plains.

...Northern Plains...

An amplified upper ridge will remain in place from the central
Plains to the Upper Midwest on Sunday. Some modest weakening of the
ridge may occur as an upper shortwave trough digs across the
Northwest and weak shortwave disturbances crest the ridge through
the period. At the surface, low pressure will persist across the
western Dakotas. Boundary layer moisture will spread across eastern
MT on the back side of the surface low, while deep low-level
moisture extends across ND into eastern SD and the Mid-MO Valley
along another surface boundary. Capping will be a main limiting
factor for storm development. However, if the cap can be overcome,
or if elevated convection develops during the day into evening,
strong wind gusts and large hail will be possible given supercell
wind profiles and corridor of moderate to strong instability.

Deep-layer southwesterly flow is forecast to increase with the
approach of the Northwest upper shortwave trough late in the period
across parts of the northern Rockies toward the northern High
Plains. This could also support possible severe convection overnight
into parts of MT, but timing and overlap of stronger shear and
better instability remains uncertain.

Overall, severe potential appears conditional on Sunday across
portions of the northern Plains. But, if storms can develop, some
risk for severe wind/hail will be possible.

...Southeast...

Weak northwesterly flow aloft will persist on Sunday as a surface
front develops south/southwest into the Southeast. Ahead of the
surface boundary, a very moist airmass will support a corridor of
moderate to strong instability focused across southern GA.
Thunderstorms are expected to develop during the afternoon. Vertical
shear will remain weak, but high PW values could support sporadic
wet microbursts and locally strong wind gusts. Some guidance
suggests sufficient clustering and outflow consolidation could occur
such that a forward propagating cluster could spread south/southwest
across the area. If this occurs, damaging wind potential could
increase.

..Leitman.. 09/04/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Fri Sep 4 19:30:22 2026

ACUS03 KWNS 041930
SWODY3
SPC AC 041929

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0229 PM CDT Fri Sep 04 2026

Valid 061200Z - 071200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF
THE SOUTHEAST...

...SUMMARY...
Strong wind gusts are likely across the Southeast Sunday afternoon
and early evening. A more uncertain risk for severe wind and hail is
expected across parts of the northern Plains.

...Southeast...
Most guidance shows a weak mid-level shortwave trough moving across
the Southeast during the day on Sunday. Moderate to strong
instability is forecast south of a cold front across the region. The
greatest instability is anticipated near the coast where low to mid
70s dewpoints are likely. Mid-level flow will be quite weak, which
should limit overall storm organization. However, the combination of
the mid-level shortwave trough and the frontal forcing amid an
uncapped and strongly unstable environment should result in a
cluster of storms capable of water-loaded downbursts. A Slight Risk
has been added for the region where the greatest storm coverage is
expected.

...Northern Plains...
The ridge across the Plains will start to break down on Sunday with
a lee cyclone developing across eastern Montana. Moderate to strong
instability will be present across the northern Plains, potentially
with some stronger mid-level flow as the ridge breaks down. Storms
will be possible along the trough from eastern Wyoming into northern
Colorado, along the warm front near the Canadian border and into
northern North Dakota, and extending into western Minnesota, and
northwest of the low across eastern Montana where some instability
is expected to develop. Within this broader area, there will likely
be a few preferred zones that will eventually need a Slight Risk.
However, at this time, it is unclear where these preferred zones
will be. Greater resolution of the pattern evolution should make
these regions more clear in later outlooks.

..Bentley.. 09/04/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sat Sep 5 06:39:18 2026

ACUS03 KWNS 050639
SWODY3
SPC AC 050637

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0137 AM CDT Sat Sep 05 2026

Valid 071200Z - 081200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE NORTHERN AND CENTRAL PLAINS INTO WESTERN MINNESOTA...

...SUMMARY...
Strong to severe thunderstorms are possible across portions of the
northern and central Plains into Minnesota on Monday.

...Nebraska into the Dakotas and Minnesota...

An upper shortwave trough will eject east/northeast from the
Intermountain West to the northern Plains on Monday. Strong
mid/upper southwesterly flow will overspread the region ahead of the
trough. At the surface, a low over eastern MT will develop northeast
into the Canadian Prairies, and a trailing cold front will push east
across portions of NE/SD/ND. A moist airmass will be in place ahead
of the front, promoting areas of moderate instability. Vertically
veering wind profiles, and strengthening midlevel southwesterly
flow, will generate effective shear magnitudes greater than 35 kt,
supporting organized thunderstorms. While cooling aloft will result
in modestly steep lapse rates, warmer temperatures may linger around
850 mb, leading to capping concerns. Nevertheless, even elevated
storms will pose a risk for hail, and depending on storm mode,
strong wind gusts.

..Leitman.. 09/05/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sat Sep 5 19:46:54 2026

ACUS03 KWNS 051945
SWODY3
SPC AC 051944

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0244 PM CDT Sat Sep 05 2026

Valid 071200Z - 081200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
OF THE NORTHERN PLAINS AND MINNESOTA...

...SUMMARY...
Strong to severe thunderstorms are possible across portions of the
northern and central Plains into Minnesota on Monday.

... Northern Plains into the Upper Great Lakes ...

A mid-level shortwave trough will lift northeast on Monday,
impinging on the central US ridge. Strong southwesterly mid-level
flow associated with the trough will overspread an increasingly warm
and moist low-level airmass across the north-central US. Given
low-level flow will be more southerly, the resulting vertically
veering profiles will result in effective shear ranging from 35
knots to more than 50 knots. Forecast soundings indicate that an
elevated mixed layer should advect over the Plains during the day
resulting in capping issues for most of the afternoon. However, as
cooler mid-level temperatures overspread the unstable and sheared
airmass, afternoon thunderstorms will at least be possible. These
storms should pose a threat for large hail and, if the storms can
tap into the boundary layer, strong thunderstorm winds. As the
low-level jet increases during the evening, an increase in storm
coverage is expected, with perhaps one or more MCSs evolving across
portions of the eastern Dakotas and Minnesota. Isolated large hail
and perhaps damaging winds will be possible.

..Marsh.. 09/05/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sun Sep 6 06:23:04 2026

ACUS03 KWNS 060622
SWODY3
SPC AC 060621

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0121 AM CDT Sun Sep 06 2026

Valid 081200Z - 091200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM NEBRASKA TO
THE UPPER MIDWEST...

...SUMMARY...
Strong to severe storms are possible on Tuesday from Nebraska into
the Upper Midwest.

...Central Plains to Upper Midwest...

An upper trough will move from the northern Plains to the Great
Lakes on Tuesday. As this occurs, a swath of enhanced deep-layer
southwesterly flow will overspread the Upper Midwest. At the
surface, low pressure over Manitoba will continue east/northeast
through the period, with a trailing cold front sweeping east across
the northern/central Plains and Upper MS Valley. A moist airmass
will be in place ahead of the front, and weak to moderate
destabilization is forecast. Deep-layer flow will largely remain
parallel to the surface boundary, but sufficient shear will be
present for some storm organization. The north and east extent of
severe potential is a bit uncertain given concern over
inhibition/timing and modest instability. However, given the
strength of deep-layer southwesterly flow, some severe risk should
extend along the length of the surface front from the Upper Midwest
into the central Plains. Damaging wind and hail will be the primary
concern with this activity from late afternoon into the nighttime
hours.

..Leitman.. 09/06/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sun Sep 6 19:28:00 2026

ACUS03 KWNS 061927
SWODY3
SPC AC 061926

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0226 PM CDT Sun Sep 06 2026

Valid 081200Z - 091200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM
NORTH-CENTRAL KANSAS INTO THE UPPER MIDWEST...

...SUMMARY...
Strong to severe storms are possible on Tuesday from Nebraska into
the Upper Midwest.

... Central Plains to the Upper Midwest ...

Showers and thunderstorms will likely be ongoing across portions of
the Upper Midwest at the start of the forecast period. These storms
will be primarily driven by strong warm-air advection along and
ahead of a surface cold front moving east across the region in
association with a short-wave trough moving across the southern
Canadian Prairies. These morning storms may pose a marginal risk for
hail and wind before weakening during the day as the low-level jet
veers and weakens.

In the wake of the morning convection, diurnal heating of a moist
airmass south of the residual surface boundary will result an
unstable airmass by late afternoon. Large scale forcing for ascent
along the boundary will be nebulous so local-scale processes will
likely govern if and where afternoon storms may develop. Vertical
shear decreases with southward extent, but a threat of large hail
and damaging winds will be possible with any afternoon
thunderstorms.

By late evening into the overnight another short-wave trough will
quickly race east into the Plains. In response to this feature, the
low-level jet will once again increase, providing some forcing for
ascent along isentropic surfaces along and north of the front. These
storms should be able to tap into elevated instability and
sufficient cloud-layer shear to support a threat for isolated wind
and hail overnight.

..Marsh.. 09/06/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Mon Sep 7 06:36:52 2026

ACUS03 KWNS 070636
SWODY3
SPC AC 070635

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0135 AM CDT Mon Sep 07 2026

Valid 091200Z - 101200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
OF THE MIDWEST...

...SUMMARY...
Isolated strong to severe thunderstorms are possible across portions
of the Midwest on Wednesday.

...Midwest...

An upper trough will progress eastward across the Great Lakes on
Wednesday, bringing enhanced westerly flow over the region. At the
surface, a cold front will shift southeast through the period,
becoming positioned from the Upper Ohio Valley to the TX Panhandle
by Thursday morning. Ahead of the front, a moist airmass will be in
place. Midlevel lapse rates are not forecast to be particularly
steep, but pockets of weak to moderate instability are forecast,
particularly across the Lower MO Valley into OH. Morning showers and thunderstorms will likely be ongoing near and north of the cold
front from Iowa into Lower MI. As the front progresses southeast
through the afternoon and evening, additional thunderstorm
development is expected across the destabilizing warm sector.

Deep-layer flow is expected to largely remain parallel to the
surface boundary. This environment should largely favor a more
linear storm mode and convection could become undercut by the front. Nevertheless, vertical shear will be sufficient for organized
convection and damaging winds appear possible within corridors of
greater instability into Wednesday evening/early Thursday.

..Leitman.. 09/07/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Mon Sep 7 18:46:44 2026

ACUS03 KWNS 071846
SWODY3
SPC AC 071845

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0145 PM CDT Mon Sep 07 2026

Valid 091200Z - 101200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ...

...SUMMARY...
Isolated strong to severe thunderstorms are possible across portions
of the central Plains to the eastern Great Lakes on Wednesday.

...Central Plains to the Lower Ohio Valley...
Moderate instability is expected as temperatures warm into the 90s
and low 100s ahead of a stalled front from the Plains to the Ozarks
on Wednesday. However, despite the strong heating and moderate
instability, very weak shear (less than 20 knots) should limit storm organization. Isolated severe wind gusts will be possible amid the
strong heating and steep lapse rates, but a more focused overall
severe weather threat does not appear likely.

...Upper Ohio Valley into New York...
A mid-level trough is forecast to cross the northern Great Lakes on
Wednesday and the associated mid-level jet streak will overspread
the Great Lakes. Most forecast guidance shows instability focused
south of the stronger mid-level flow with only very weak instability
across western New York where the stronger mid-level flow will be
present. Therefore, the displacement of the stronger mid-level flow
and instability should limit a more organized severe weather threat,
but some stronger instability in the Ohio Valley may support
isolated damaging wind gusts, and a more conditional threat may
exist across western New York if sufficient instability can develop.

..Bentley.. 09/07/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Mon Sep 7 18:50:26 2026

ACUS03 KWNS 071849
SWODY3
SPC AC 071848

Day 3 Convective Outlook CORR 1
NWS Storm Prediction Center Norman OK
0148 PM CDT Mon Sep 07 2026

Valid 091200Z - 101200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE CENTRAL
PLAINS TO THE EASTERN GREAT LAKES...

CORRECTED FOR MISSING HEADLINE

...SUMMARY...
Isolated strong to severe thunderstorms are possible across portions
of the central Plains to the eastern Great Lakes on Wednesday.

...Central Plains to the Lower Ohio Valley...
Moderate instability is expected as temperatures warm into the 90s
and low 100s ahead of a stalled front from the Plains to the Ozarks
on Wednesday. However, despite the strong heating and moderate
instability, very weak shear (less than 20 knots) should limit storm organization. Isolated severe wind gusts will be possible amid the
strong heating and steep lapse rates, but a more focused overall
severe weather threat does not appear likely.

...Upper Ohio Valley into New York...
A mid-level trough is forecast to cross the northern Great Lakes on
Wednesday and the associated mid-level jet streak will overspread
the Great Lakes. Most forecast guidance shows instability focused
south of the stronger mid-level flow with only very weak instability
across western New York where the stronger mid-level flow will be
present. Therefore, the displacement of the stronger mid-level flow
and instability should limit a more organized severe weather threat,
but some stronger instability in the Ohio Valley may support
isolated damaging wind gusts, and a more conditional threat may
exist across western New York if sufficient instability can develop.

..Bentley.. 09/07/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Tue Sep 8 06:33:22 2026

ACUS03 KWNS 080632
SWODY3
SPC AC 080632

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0132 AM CDT Tue Sep 08 2026

Valid 101200Z - 111200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
Severe thunderstorm potential appears low on Thursday.

...Discussion...

An upper trough will migrate across the Northeast on Thursday, while
a second upper trough digs southward across the northwestern U.S.
Stronger flow associated with these features will remain confined to
the northern Rockies vicinity and over New England. High pressure
will build over the Midwest and Mid-Atlantic region in the wake of a
prior cold frontal passage. A seasonally moist boundary layer will
be in place from the central/southern High Plains through the southern/southeastern U.S. Pockets of stronger heating and modest destabilization across the warm sector will support scattered
thunderstorm development. However, generally weak vertical shear
will limit organized severe potential, especially given a lack of
focus for severe storm development.

The exception may be with a strong storm or two across the
central/southern High Plains in a post-frontal upslope flow regime.
A stalled front will become diffuse across the area on Thursday, but
vertically veering wind profiles could result in some modestly
enhanced vertical shear. Some guidance shows early day convection
and cloud cover across this area, resulting in uncertainty in storm
coverage during the afternoon and evening. Furthermore, lapse rates
will remain modest and low-level flow will be weak, precluding
severe probabilities at this time.

..Leitman.. 09/08/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Tue Sep 8 18:50:32 2026

ACUS03 KWNS 081850
SWODY3
SPC AC 081849

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0149 PM CDT Tue Sep 08 2026

Valid 101200Z - 111200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
Severe thunderstorm potential appears low on Thursday.

...Discussion...
As a mid-level trough moves into the western Atlantic on Thursday,
surface high pressure will build into the Midwest/Great Lakes in its
wake. South of this high pressure center a front will extend from
Virginia to the central Plains. An expansive area of precipitation
is expected along this front at the beginning of the period which
should result in lesser instability, particularly east of the
Appalachians. Farther west, moderate instability is expected near
the front from the Lower Ohio Valley to the southern High Plains.
Mid-level flow (and thus deep-layer shear) will be weak across much
of this zone. Therefore, greater instability and storm clustering
will likely be necessary for a marginal severe weather threat. This
may occur across portions of the Ozarks or the southern High Plains,
but the signal is weak at this time. Therefore, no severe weather
probabilities are warranted.

A mid-level trough will translate quickly eastward across the
Northwest on Thursday with ascent overspreading north-central
Montana by Thursday night. A few fast-moving storms are expected
across north-central Montana late Thursday night and early Friday
morning amid weak instability. Despite the dynamic system, weak
instability and unfavorable diurnal timing preclude severe weather probabilities at this time.

..Bentley.. 09/08/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Wed Sep 9 06:25:50 2026

ACUS03 KWNS 090625
SWODY3
SPC AC 090624

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0124 AM CDT Wed Sep 09 2026

Valid 111200Z - 121200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF
THE MID-MISSOURI VALLEY INTO THE UPPER MIDWEST...

...SUMMARY...
Severe thunderstorms are possible across portions of the Upper
Midwest late Friday afternoon into Friday night.

...Upper Midwest into Nebraska...

An upper shortwave trough will move across the northern Plains and
Upper Midwest on Friday. This will result in enhanced westerly flow
and cooling aloft across the region, mainly after 00z. A surface
cold front is forecast to develop southeast across the Dakotas
through the afternoon, and continue east/southeast across the Upper
Midwest and portions of the central Plains through the nighttime
hours. Southerly low-level flow will transport 60s dewpoints
northward across the MO Valley into MN ahead of the front. Northward
advection of low-level moisture beneath cooling aloft/steepening
midlevel lapse rates will lead to at least a narrow corridor of
moderate destabilization during the late afternoon into evening from central/eastern NE into MN. Stronger large-scale ascent and vertical
shear will be focused across MN. With southward extent, instability
may be greater, but shear and large-scale ascent will be weaker.
Additionally, warmer midlevel temperatures may persist further
south, resulting in capping and a more conditional severe risk.
Large hail and damaging gusts appear to be the predominant hazard
with storms from late Friday afternoon into the nighttime hours.

..Leitman.. 09/09/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Wed Sep 9 07:00:56 2026

ACUS03 KWNS 090700
SWODY3
SPC AC 090659

Day 3 Convective Outlook CORR 1
NWS Storm Prediction Center Norman OK
0159 AM CDT Wed Sep 09 2026

Valid 111200Z - 121200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF
THE MID-MISSOURI VALLEY INTO THE UPPER MIDWEST...

CORRECTED FOR GENERAL THUNDERSTORM LINES

...SUMMARY...
Severe thunderstorms are possible across portions of the Upper
Midwest late Friday afternoon into Friday night.

...Upper Midwest into Nebraska...

An upper shortwave trough will move across the northern Plains and
Upper Midwest on Friday. This will result in enhanced westerly flow
and cooling aloft across the region, mainly after 00z. A surface
cold front is forecast to develop southeast across the Dakotas
through the afternoon, and continue east/southeast across the Upper
Midwest and portions of the central Plains through the nighttime
hours. Southerly low-level flow will transport 60s dewpoints
northward across the MO Valley into MN ahead of the front. Northward
advection of low-level moisture beneath cooling aloft/steepening
midlevel lapse rates will lead to at least a narrow corridor of
moderate destabilization during the late afternoon into evening from central/eastern NE into MN. Stronger large-scale ascent and vertical
shear will be focused across MN. With southward extent, instability
may be greater, but shear and large-scale ascent will be weaker.
Additionally, warmer midlevel temperatures may persist further
south, resulting in capping and a more conditional severe risk.
Large hail and damaging gusts appear to be the predominant hazard
with storms from late Friday afternoon into the nighttime hours.

..Leitman.. 09/09/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Wed Sep 9 19:32:18 2026

ACUS03 KWNS 091932
SWODY3
SPC AC 091930

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0230 PM CDT Wed Sep 09 2026

Valid 111200Z - 121200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EASTERN SOUTH
DAKOTA INTO MUCH OF WESTERN MINNESOTA...AND INTO CENTRAL NEBRASKA...

...SUMMARY...
Severe thunderstorms are possible across portions of the Upper
Midwest late Friday afternoon into Friday night.

...Discussion...
A leading shortwave trough will move into the Northern Plains on
Friday, as an upper low drops south along the Pacific Northwest. A
pre-frontal trough will develop into northern MN, extending into
eastern SD and central NE by late afternoon. Ahead of this trough,
strong heating will occur from NE into SD, with a cooler boundary
layer into central MN.

Temperatures aloft will cool with the upper wave, resulting in
moderately steep lapse rates aloft. Midlevel wind speeds of 20-40
kt, combined with low-level southerlies (including 40 kt at 850 mb
late in the day) will favor a few supercells initially before storms
become linear along the advancing cold front.

Forecast soundings indicate large hail will be likely with the
initial cellular activity, though shear in the mid to upper levels
will not be particularly strong. As such, will not add any sig
hatching for hail.

A brief tornado may occur with initial supercells, particularly from
eastern SD into western MN where low-level shear will be strongest.
Otherwise, damaging winds will be possible through the evening as
storms move northeast across MN.

..Jewell.. 09/09/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Wed Sep 9 20:22:20 2026

ACUS03 KWNS 092022
SWODY3
SPC AC 092020

Day 3 Convective Outlook RESENT 1
NWS Storm Prediction Center Norman OK
0320 PM CDT Wed Sep 09 2026

Valid 111200Z - 121200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EASTERN SOUTH
DAKOTA INTO MUCH OF WESTERN MINNESOTA...AND INTO CENTRAL NEBRASKA...

...SUMMARY...
Severe thunderstorms are possible across portions of the Upper
Midwest late Friday afternoon into Friday night.

...Discussion...
A leading shortwave trough will move into the Northern Plains on
Friday, as an upper low drops south along the Pacific Northwest. A
pre-frontal trough will develop into northern MN, extending into
eastern SD and central NE by late afternoon. Ahead of this trough,
strong heating will occur from NE into SD, with a cooler boundary
layer into central MN.

Temperatures aloft will cool with the upper wave, resulting in
moderately steep lapse rates aloft. Midlevel wind speeds of 20-40
kt, combined with low-level southerlies (including 40 kt at 850 mb
late in the day) will favor a few supercells initially before storms
become linear along the advancing cold front.

Forecast soundings indicate large hail will be likely with the
initial cellular activity, though shear in the mid to upper levels
will not be particularly strong. As such, will not add any sig
hatching for hail.

A brief tornado may occur with initial supercells, particularly from
eastern SD into western MN where low-level shear will be strongest.
Otherwise, damaging winds will be possible through the evening as
storms move northeast across MN.

..Jewell.. 09/09/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Thu Sep 10 06:27:04 2026

ACUS03 KWNS 100626
SWODY3
SPC AC 100625

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0125 AM CDT Thu Sep 10 2026

Valid 121200Z - 131200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
OF KANSAS INTO SOUTHERN IOWA AND NORTHERN MISSOURI...

...SUMMARY...
Isolated strong to severe thunderstorms are possible on Saturday
across parts of Kansas into southern Iowa and northern Missouri.

...Central Plains to southern IA/northern MO...

Broad upper troughing will overspread the Great Lakes to the
Northeast while shortwave upper ridging develops over the high
Plains ahead of another upper trough moving into the Northwest. This
pattern is will keep any stronger westerly flow aloft across the
northern tier of the U.S. However, a cold front is expected to
extend from the western Great Lakes into northern KS by midday. The
front will gradually move south/southeast across IA into northern
MO, while the western extent of the boundary stalls and weakens over
KS. A very moist airmass will be in place ahead of the surface
boundary from KS into the Mid-MS Valley while a plume of steep
midlevel lapse rates spread eastward across the region. This will
result in a corridor of moderate to strong instability from central
KS into southern IA/northern MO. Vertical shear will be modest, but
sufficient for at least transient organized convection. Hail and
strong wind gusts will be possible with any storms that can develop
within the weakly forced regime along the front. Some guidance
suggests additional convection may develop along the stalled
boundary across KS during the nighttime hours as a southwesterly
low-level jet increases. If this occurs, some potential for MCS
development will exist.

..Leitman.. 09/10/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Thu Sep 10 19:04:28 2026

ACUS03 KWNS 101904
SWODY3
SPC AC 101903

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0203 PM CDT Thu Sep 10 2026

Valid 121200Z - 131200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM KANSAS INTO
NORTHERN MISSOURI...

...SUMMARY...
Isolated strong to severe thunderstorms are possible on Saturday
across parts of Kansas into southern Iowa and northern Missouri.

...Discussion...
A large upper low/trough will progress eastward across northern
Manitoba and Ontario, with stronger flow aloft over the Northern
Plains and Upper Great Lakes. Much of that area will become stable
due to high pressure building southward into NE/IA.

The wind shift with the associated cold front will push into KS and
northern MO, beneath the southern fringe of the 30 kt midlevel
westerlies. At the surface, strong heating will occur south of the
cold front, with gradual height rises.

While predictability is low, isolated strong to perhaps severe
storms cannot be ruled out near the cold front where mid 60s F
dewpoints will persist, and CIN should be minimal at peak heating.
MUCAPE of 2000+ J/kg seems reasonable, and the steep lapse rate
profiles along with winds lightly veering with height should support
locally strong to severe gusts with multicellular storm mode. It is
uncertain how many storms may form due to the upper ridging.

..Jewell.. 09/10/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Fri Sep 11 07:32:18 2026

ACUS03 KWNS 110731
SWODY3
SPC AC 110730

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0230 AM CDT Fri Sep 11 2026

Valid 131200Z - 141200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS SUNDAY INTO
SUNDAY NIGHT ACROSS A CORRIDOR FROM WESTERN NEW ENGLAND THROUGH THE
UPPER OHIO VALLEY AND ANOTHER CORRIDOR FROM NEAR AND SOUTHWEST OF
THE BLACK HILLS THROUGH PORTIONS OF THE MIDDLE MISSOURI VALLEY...

...SUMMARY...
Strong storms accompanied by at least some risk for severe weather
appears possible across parts of the Northeast into Ohio Valley, and
across parts of the north central Great Plains, Sunday into Sunday
night.

...Discussion...
An initially notable mid-level low inland of the Pacific Northwest
coast by 12Z Sunday is forecast to remain progressive through this
period, though it may slowly begin to devolve into an open trough
while accelerating across the northern U.S. Rockies in response to a
short wave digging into northwestern portions of the Canadian
Prairies. Within the downstream westerlies, models indicate that
short wave ridging will build across the northern U.S. Great Plains
and adjacent Canadian Prairies through the Upper Midwest/adjacent
northwestern Ontario, while downstream troughing digs across Quebec
through the lower Great Lakes region.

The primary surface cyclone associated with eastern troughing is
forecast to migrate from northern Quebec into the Labrador Sea by
late Sunday night. As it does, the trailing cold front probably
will advance southeast of the lower Great Lakes region by late
Sunday afternoon, before overspreading the northern Atlantic
Seaboard through upper Ohio Valley by the end of the period.
Westward through the Ohio and middle Mississippi Valleys into the
central Great Plains, it appears that this front may stall near or
just south of the stronger westerlies.

...Parts of western New England into the Ohio Valley...
Models vary concerning the degree of pre-frontal destabilization and
the extent to which this may coincide with strengthening of westerly
flow in the 700-500 mb layer, downstream of the digging short wave
trough. However, particularly to the lee of the lower Great Lakes
toward the northern Mid Atlantic vicinity, it appears that forcing
for ascent will become increasingly conducive to at least scattered thunderstorm development by or shortly after peak daytime heating.
As this occurs, developing storms will probably be accompanied by at
least some risk for damaging wind gusts before weakening Sunday
evening.

...North central Great Plains/Middle Missouri Valley vicinity...
The degree to which cool/stable boundary-layer air remains
entrenched across much of Nebraska into parts of northern Kansas, to
the south of the westerlies and beneath a remnant plume of warm
elevated mixed-layer air, remains unclear. Between the cool
boundary layer, which may be relatively shallow, and the base of the
capping elevated mixed layer, it does appear that a seasonably moist
air mass retreating northward through the region will contribute to
moderate to large CAPE.

Although notable spread exists within/among the various model
output, there appears potential for at least isolated to widely
scattered strong to severe storm development in moistening
southeasterly low-level flow across and to the southwest of the
Black Hills vicinity by late Sunday afternoon, with the approach of
the short wave trough. Subsequent development eastward into the
Great Plains remains more uncertain, but, by late Sunday night,
stronger storm development seems most likely to focus on the nose of
a strengthening southerly low-level jet, near the northeastern
periphery of the plume of elevated mixed-layer air, across/northeast
of the middle Missouri Valley. This may be accompanied by at least
a risk for severe hail.

..Kerr.. 09/11/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Fri Sep 11 19:22:34 2026

ACUS03 KWNS 111922
SWODY3
SPC AC 111921

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0221 PM CDT Fri Sep 11 2026

Valid 131200Z - 141200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PARTS OF
THE NORTHEASTERN STATES...AND NORTHERN PLAINS...

...SUMMARY...
Strong storms accompanied by at least some risk for severe weather
may occur across parts of the Northeast, and across parts of the
north central Great Plains Sunday into Sunday night.

...Ohio into the Northeast...
A large upper low/trough will push across eastern Canada on Sunday,
with a strong speed max aloft spreading across the Great Lakes late
in the day. A cold front will push toward the OH Valley and Lower
Great Lakes late in the day, with a moist and marginally unstable
air mass ahead of it. Areas of heating and lift near the boundary
should support scattered afternoon/evening storms, and deep-layer
shear of 30 to perhaps 40 kt could support a degree of organization.
Lapse rates aloft appear to be poor overall, suggesting only a
Marginal Risk of damaging gusts or hail will exist.

...Northern Plains...
High pressure will move from the northern Plains to the Upper Great
Lakes as shortwave ridging occurs over the Plains during the day. A
compact yet deep upper low is then forecast to move into the
northern Rockies, with height falls increasing over the northern
High Plains Sunday night.

The steeper low-level lapse rates will be confined to the higher
terrain from east-central WY to the Front Range in CO, with
generally stable low levels to the east due to high pressure. After
a days worth of heating, isolated surface-based storms may occur
late over eastern WY, with additional activity developing within the
warm advection regime as the low-level jet increases over the
central Plains. The overall threat appear minimal, and likely in the
form of marginal hail.

..Jewell.. 09/11/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sat Sep 12 07:15:42 2026

ACUS03 KWNS 120715
SWODY3
SPC AC 120714

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0214 AM CDT Sat Sep 12 2026

Valid 141200Z - 151200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS LATE MONDAY INTO
MONDAY NIGHT ACROSS PARTS OF THE CENTRAL GREAT PLAINS INTO UPPER
MIDWEST...

...SUMMARY...
Strong thunderstorm development, accompanied by at least some risk
for severe weather, appears possible across parts of the central
Great Plains into Upper Midwest late Monday through Monday night.

...Discussion...
Downstream of weak mid/upper troughing continuing to slowly dig
across the Pacific coast, models indicate that mid/upper ridging
(centered across the Southeast) may become increasingly prominent
across the southern Great Plains into the lower Great Lakes and
northern Mid Atlantic Seaboard through this period. To the north of
this ridging, and in advance of a short wave impulse digging through
the Canadian Prairies, a notable remnant mid-level cyclonic
circulation is forecast to accelerate more rapidly east-northeast of
the northern U.S. Rockies, across the international border into
northwestern Ontario by late Monday night. It appears that this
will be accompanied by modest surface cyclogenesis, and considerable strengthening of south to southwesterly lower/mid-tropospheric wind
fields across much of the northern U.S. Great Plains through Upper Midwest/Great Lakes region.

While an associated increase in vertical shear will contribute to an environment conditionally supportive of organized severe weather
potential, destabilization within the warm sector remains much more
uncertain. There does remain a general consensus among the various
model output that a northward retreating near-surface baroclinic
zone may provide the primary focus for stronger convective
development, generally near the southern fringe of the westerlies,
from parts of eastern Nebraska northeastward toward the Upper
Midwest. However, even if the maintenance of a relatively cold,
stable boundary layer along this zone, as depicted in the latest NAM
forecast soundings, is too extreme, it remains unclear the extent to
which thermodynamic profiles will become conducive to the risk for
severe weather.

..Kerr.. 09/12/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sat Sep 12 19:13:56 2026

ACUS03 KWNS 121913
SWODY3
SPC AC 121912

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0212 PM CDT Sat Sep 12 2026

Valid 141200Z - 151200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF
EASTERN NEBRASKA INTO WESTERN IOWA...

...SUMMARY...
Strong thunderstorm development, accompanied by at least some risk
for severe weather, appears possible across parts of the central
Great Plains into Upper Midwest late Monday through Monday night.

...Discussion...
A mid-level trough will move across the northern Plains on Monday
with a strengthening 60-70 knot mid-level jet streak. The surface
pattern will feature a surface low across the Canadian Prairies and
a secondary weaker surface low across the central Plains. A moist
airmass will advect northward to the east of the surface trough with
mid to upper 60s dewpoints advecting into Nebraska and Iowa.

Thunderstorms will likely be ongoing at the beginning of the period
across eastern South Dakota and Minnesota amid moderate isentropic
ascent. The primary forecast concern for Monday will be northward
progression of the surface boundary across eastern Nebraska and
Iowa. Guidance varies with the northward recovery in the wake of
morning activity, but forecast soundings in regions where this
recovery does occur show a conditional supercell environment with
the threat for all severe weather hazards.

Given the influence of morning convection, the exact location of the
greatest threat will likely shift in the coming days. However, given
that most guidance showed a convective signal aligned with a
conditionally favorable supercell environment in the vicinity of
eastern Nebraska and western Iowa, added a small Slight Risk across
this region to account for this threat.

An elevated hail threat may persist into Monday evening farther
northeast given a strong low-level jet and moderate elevated
instability. Some surface based storm threat could continue into the
overnight hours along the boundary, but most guidance shows storms
north of the boundary during the overnight period.

Storms will likely form within the well-mixed environment across
eastern Colorado and western Kansas Monday afternoon. Weak shear
should limit storm organization, but strong heating and steep lapse
rates may support isolated severe wind gusts.

..Bentley.. 09/12/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sun Sep 13 07:05:48 2026

ACUS03 KWNS 130705
SWODY3
SPC AC 130704

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0204 AM CDT Sun Sep 13 2026

Valid 151200Z - 161200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS TUESDAY
AFTERNOON INTO EVENING IN A CORRIDOR SOUTH/SOUTHWEST OF THE GREAT
LAKES THROUGH THE LOWER MISSOURI VALLEY...

...SUMMARY...
Scattered strong thunderstorms may impact a corridor south to
southwest of the Great Lakes through the lower Missouri Valley
Tuesday afternoon and evening, accompanied by at least some risk for
locally damaging wind gusts.

...Discussion...
A deamplifying mid-level short wave trough and associated surface
cyclone are forecast to continue an east-northeastward migration
through this period, generally across the remainder of northwestern
Ontario through much of northern Quebec by late Tuesday night. In
the wake of the cyclone, an initial low-level baroclinic zone across
the lower Great Lakes region through the lower Missouri Valley and
central Great Plains may make some southward progression, before
stalling and perhaps retreating northward beneath the building
northwestern periphery of prominent ridging still centered across
the Southeast. There is variance among the guidance concerning this
latter development, and the evolution of digging upstream mid-level
troughing across the northern Intermountain Region and Pacific
Coast.

...Southern Great Lakes through central Great Plains...
Mainly where mid-level heights remain suppressed, prior to the onset
of the mid-level height rises, coincident with daytime
boundary-layer destabilization along and southeast of the slow
moving frontal zone, a corridor of increasing, scattered
thunderstorm development appears possible through mid to late
Tuesday afternoon. Steepening low-level lapse rates may support the
evolution of moderate mixed-layer CAPE on the order of 1000-2000+
J/kg, near the modest southern fringe of the mid-level westerlies,
which may still include speeds of 30+ kts in the 700-500 mb layer.
A warm layer in mid/upper levels may tend to suppress large hail,
but thermodynamic profiles characterized by steep lapse rates of
potential wet-bulb temperatures in lower/mid-levels could contribute
to a few downbursts and developing cold pools with a few strong
gusts into Tuesday evening.

..Kerr.. 09/13/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sun Sep 13 19:26:22 2026

ACUS03 KWNS 131926
SWODY3
SPC AC 131925

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0225 PM CDT Sun Sep 13 2026

Valid 151200Z - 161200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE CENTRAL
PLAINS TO THE GREAT LAKES...

...SUMMARY...
Scattered strong thunderstorms may impact a corridor south to
southwest of the Great Lakes through the lower Missouri Valley
Tuesday afternoon and evening, accompanied by at least some risk for
locally damaging wind gusts.

...Discussion...
A mid-level trough will move into Ontario on Tuesday with the
mid-level ridge building in its wake across the Midwest and into the
Upper Midwest. Beneath this ridge, a cold front will move slowly
southeastward from southern Iowa and northern Kansas at the
beginning of the period, to northern Oklahoma to central Missouri by
the end of the period. Dewpoints will increase into the low to mid
70s south of the front with weak to moderate instability
anticipated. Forcing will be somewhat nebulous given the rising
heights aloft and weak convergence along the slow-moving, decaying
front.

Nonetheless, moderate to potentially strong instability and an
uncapped airmass should support some thunderstorms capable of severe
wind gusts. Some lingering 30 to 40 knot mid-level flow is forecast
to remain across portions of the warm sector Friday afternoon
(particularly across northern Illinois/Indiana) which may aid in
storm organization, but warm air aloft and a lack of clear supercell
mode should limit the overall hail threat.

..Bentley.. 09/13/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Mon Sep 14 07:26:54 2026

ACUS03 KWNS 140726
SWODY3
SPC AC 140725

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0225 AM CDT Mon Sep 14 2026

Valid 161200Z - 171200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
The risk for severe thunderstorms appears negligible (i.e, less than
5 percent probabilities) across the U.S. Wednesday through Wednesday
night.

...Discussion...
It appears that an initially digging short wave trough along the
Pacific coast will contribute to the evolution of a mid/upper low
centered across northern California by or shortly after the
beginning of this period. There it is forecast to generally remain,
cut off from the stronger westerlies confined to the northern
mid-latitudes.

A couple of notable short wave perturbations will remain progressive
within a stronger confluent mid/upper regime across the eastern
Canadian Provinces through northern mid-latitude Atlantic, including
one forecast to translate east of Newfoundland and Labrador and
another digging through northern Manitoba and northwestern Ontario.

In lower latitudes, mid-level ridging likely will remain prominent
across much of the central and southern Great Plains through
northern Mid Atlantic. More uncertainty exists concerning an
easterly wave approaching the Florida Peninsula and a possible
mid-level perturbation suppressing the ridging across parts of the
lower Great Lakes/upper Ohio Valley vicinity.

Based on current model output, a remnant surface frontal zone across
the Ohio into lower Missouri Valleys will remain a focus for higher
boundary layer moisture content and the development of moderate CAPE
with insolation. However, there is spread concerning the degree to
which this front remains quasi-stationary, or begins to return
northward toward at least a bit more of a favorably sheared regime
for organized convection. Given this uncertainty, and the otherwise marginal/isolated nature of the anticipated severe weather
potential, severe probabilities for Wednesday through Wednesday
night appear less than 5 percent at this time.

..Kerr.. 09/14/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Mon Sep 14 19:17:24 2026

ACUS03 KWNS 141917
SWODY3
SPC AC 141916

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0216 PM CDT Mon Sep 14 2026

Valid 161200Z - 171200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
The risk for severe thunderstorms appears negligible across the U.S.
on Wednesday.

...Discussion...
Stronger winds aloft will extend from the Northern Plains into the
Upper Great Lakes on Wednesday as a large upper ridge expands across
much of the central to southeastern states. A surface high will also
exist over the Upper MS Valley and Great Lakes which will keep the
more favorable instability well south of the stronger flow/shear.
While a secondary shortwave trough will swing across central Canada
and into the northern Plains late, instability should be minimal
that far north.

The greatest chance of thunderstorms will be near a weak/stalled
front from the Central Plains eastward across the Midwest and OH
Valley, where dewpoints of 65-70 F will be common. Early day
thunderstorms across this same zone will likely dissipate during the
day, with scattered redevelopment near peak heating. Given the
generally poor lapse rates aloft and weak shear, the severe storm
threat appears low.

..Jewell.. 09/14/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Tue Sep 15 07:31:30 2026

ACUS03 KWNS 150731
SWODY3
SPC AC 150730

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0230 AM CDT Tue Sep 15 2026

Valid 171200Z - 181200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
The risk for organized severe thunderstorms currently appears
negligible for Thursday through Thursday night.

...Discussion...
It appears that mid-level ridging will remain prominent across much
of the central and southern Great Plains, middle and lower
Mississippi and Ohio Valleys through this period. A wave migrating
on its southeastern periphery may gradually overspread portions of
the south Atlantic Seaboard by late Thursday night. To its
northwest, a cut-off low, initially inland of the northern
California coast, may elongate north-northeastward through portions
of the northern Intermountain Region and Great Basin.

Within the stronger westerlies, consolidating large-scale mid-level
troughing is forecast to dig through northern Ontario, Quebec and
adjacent portions of the Northeast. It appears that this will be
accompanied by a developing area of surface low pressure, trailed by
a reinforcing cool intrusion across the upper Great Lakes region and
adjacent portions of the Upper Midwest. A preceding front may
progress southeastward across the northern Mid Atlantic and upper
into middle Ohio Valley, perhaps overtaking portions of an initially quasi-stationary boundary across the lower Ohio through lower/middle
Missouri Valley vicinity.

Guidance suggests that seasonably high boundary-layer moisture
content along the southern-most baroclinic zone will once again
contribute to sizable CAPE with insolation Thursday. However,
generally warm thermodynamic profiles and weak deep-layer mean
flow/shear probably will continue to inhibit the risk for organized
severe thunderstorm activity.

If forcing for ascent, associated with a subtle perturbation
migrating through the northern periphery of the ridge, can support a sufficiently upscale growing thunderstorm cluster, then the
environment might be conducive to the evolution of a meso-beta scale
cyclonic circulation with strengthening rear inflow and potential to
produce strong to severe surface gusts. While the potential for
this remains uncertain at the present time, trends will continue to
be monitored in later outlooks for this period.

..Kerr.. 09/15/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Tue Sep 15 19:12:02 2026

ACUS03 KWNS 151911
SWODY3
SPC AC 151910

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0210 PM CDT Tue Sep 15 2026

Valid 171200Z - 181200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
The risk for severe thunderstorms appears low on Thursday.

...Discussion...
On Thursday, a large upper trough will move into eastern Canada,
with height falls with the base of the trough moving across the
Great Lakes and into the Northeast. Meanwhile, heights will fall
over the Southeast as the upper high center shifts back west into
the southern Plains. To the west, an upper low will drift from
northern CA into southern OR, with cool temperatures aloft over much
of the Great Basin.

At the surface, high pressure will remain over the northern Plains
to Great Lakes, with a weak surface trough extending from the
central Plains into the OH Valley and toward the Mid Atlantic. Upper
60s to lower 70s F dewpoints will remain along this zone, resulting
in areas of moderate instability. Weaker instability will exist
ahead of the Pacific Northwest low, and ahead of a cold front
pushing across northern NV, eastern OR, and western ID.

Severe storm chances appear relatively low over the Pacific
Northwest given weak instability and marginal shear, while the zone
from MO into PA suffers from poor lapse rates aloft and/or minimal
shear.

..Jewell.. 09/15/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Wed Sep 16 07:31:38 2026

ACUS03 KWNS 160731
SWODY3
SPC AC 160730

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0230 AM CDT Wed Sep 16 2026

Valid 181200Z - 191200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS LATE FRIDAY
AFTERNOON AND EVENING ACROSS PARTS OF NORTHWESTERN KANSAS...SOUTH
CENTRAL AND EASTERN NEBRASKA...ADJACENT SOUTHEASTERN SOUTH DAKOTA
...WESTERN AND CENTRAL IOWA...

...SUMMARY...
Strong thunderstorms may impact portions of the central Great Plains
through southern portions of the middle Missouri Valley late Friday
afternoon and evening, accompanied by at least some risk for severe
weather.

...Discussion...
A vigorous short wave trough in the westerlies is forecast to dig
across the northern Atlantic Seaboard accompanied by significant
surface cyclogenesis near and east of the Canadian Maritimes. In
the wake of the cyclone, it appears that a cold front will continue
advancing offshore and through the southern Mid Atlantic Seaboard.
A trailing low-level baroclinic zone may remain more or less
quasi-stationary across the lower Ohio and lower/mid Missouri
Valleys into northern high plains, beneath a weaker belt of
westerlies in the southern mid-latitudes.

Within this regime, a mid-level trough and embedded low are forecast
to slowly progress across the Intermountain West through Rockies
vicinity, preceded by a more subtle perturbation crossing the middle
Missouri Valley. The latter impulse, and another westward migrating
wave across the Florida Peninsula vicinity may contribute to further suppression of persistent mid-level ridging, which may otherwise
maintain a considerable influence across a shrinking corridor
centered across the southern Great Plains through Tennessee Valley.

...Central Great Plains through southern Mid Missouri Valley...
Convective potential remains uncertain for Friday through Friday
night. However, latest model output suggests that the mid-level
perturbation overspreading the middle Missouri Valley will be
accompanied by a moderate jet including 30-40 kt southwesterly flow
in the 850-700 mb layer overspreading the central Great Plains
through upper Mississippi Valley.

As insolation contributes to a more strongly heated and deeply mixed
boundary layer along modestly deepening surface troughing
coincident with the low-level jet axis, there may be sufficient
moisture to support scattered thunderstorm development capable of
producing a few strong downbursts across parts of northwestern
Kansas through south central Nebraska late Friday afternoon and
evening.

Closer to a weak developing frontal wave near the Missouri River,
roughly between Omaha and Sioux City, seasonably high boundary-layer
moisture content along a warm frontal zone to its south may support
a corridor of sizable CAPE and potential for much more vigorous
thunderstorm development. Lower/mid-tropospheric inhibition might
remain an issue concerning boundary-layer based thunderstorm
development, but a late afternoon/early evening supercell and small
upscale growing cluster do not appear out of the question, before
storms become elevated while spreading southeastward through
portions of central Iowa during the evening.

..Kerr.. 09/16/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Wed Sep 16 19:30:10 2026

ACUS03 KWNS 161929
SWODY3
SPC AC 161928

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0228 PM CDT Wed Sep 16 2026

Valid 181200Z - 191200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR THE MIDDLE
MISSOURI VALLEY AND VICINITY...

...SUMMARY...
A few severe storms will be possible from eastern Nebraska into Iowa
and northern Kansas, mainly Friday afternoon/evening.

...Synopsis...
A midlevel high will persist over TX and vicinity as the current
closed low over northern CA begins to progress eastward across the
northern Great Basin. Around the northern periphery of the TX
midlevel high, there is the potential for an MCV to emerge from
overnight convection late Thursday into Friday morning near the mid
MO Valley (NE/IA), with an associated weak wave along a slow-moving
baroclinic zone. Assuming an MCV develops, some enhancement to wind
profiles and associated vertical shear can be expected, which would
support some organized/supercell storm potential in a narrow zone
along the path of the MCV. Higher-based thunderstorm development
may also occur along the trailing front/wind shift into KS where
strong surface heating and deep mixing will favor inverted-V
profiles and at least isolated strong-severe outflow gusts.

Otherwise, scattered thunderstorms will again occur across the
central/northern Rockies downstream from the Great Basin midlevel
trough. A few pockets of stronger surface heating/destabilization
could coincide with at least 30 kt midlevel flow and support the
low-end potential for strong outflow gusts. This area will be
monitored in later updates, but the severe threat appears to be too
marginal to introduce severe probabilities this far in advance.

..Thompson.. 09/16/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Thu Sep 17 07:31:50 2026

ACUS03 KWNS 170731
SWODY3
SPC AC 170730

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0230 AM CDT Thu Sep 17 2026

Valid 191200Z - 201200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS SATURDAY INTO
SATURDAY EVENING ACROSS PARTS OF THE MIDDLE MISSISSIPPI VALLEY
THROUGH CENTRAL AND SOUTHERN GREAT PLAINS AND NEAR THE FRONT RANGE
OF THE ROCKIES...

...SUMMARY...
Isolated to widely scattered strong storms posing some risk for
severe wind and hail are possible across parts of the middle
Mississippi Valley into central and southern Great Plains, and east
of the Front Range, Saturday afternoon and evening.

...Discussion...
The stronger westerlies will remain confined to the northern
mid-latitudes, with mid-level troughing forecast to dig across
Hudson Bay, Ontario and Quebec, downstream of broad ridging
overspreading the Canadian Prairies, and in the wake of a
significant cyclone migrating away from the Canadian Maritimes. In
response to these developments, it appears that cool surface ridging
will be maintained to the east of the southern Appalachians, while
the associated high center shifts off the northern Atlantic
Seaboard. Another modest high is forecast to begin shifting across
the central Canadian/U.S. border through much of the northern Great
Plains, Upper Midwest and adjacent upper Great Lakes by late
Saturday night.

This will be preceded by a notable cold front advancing slowly
southward into/across the Ohio and lower Missouri Valleys and
central Great Plains, beneath a weaker belt of westerlies across the
southern mid-latitudes. Within this regime, broad mid-level
troughing is forecast to continue a slow eastward progression across
the Rockies through central Great Plains, downstream of weak
troughing slowly approaching the California coast.

Mid-level ridging downstream of the lead trough will become
increasingly suppressed across the southeastern Great Plains through
lower to middle Mississippi Valley vicinity. A perturbation along
it southeastern periphery may continue slowly west-southwestward
across Florida and the northeastern Gulf Basin.

...Front Range vicinity into middle Mississippi Valley...
Generally warm thermodynamic profiles and modest to weak wind
vertical shear to the east of the Rockies will continue to limit the
severe weather potential, but isolated to widely scattered strong
thunderstorm development posing at least some risk for severe wind
and/or hail appear possible in a few evolving regimes Saturday into
Saturday night.

Convection with potential to produce strong surface gusts may be
supported by the evolution of a very warm and deeply mixed boundary
layer by late afternoon within weak pre-frontal surface troughing
across parts of eastern New Mexico, parts of the Texas South Plains
Panhandle and northwestern Oklahoma into southeastern Kansas.

Seasonably high moisture content and lift along the low-level
baroclinic zone across the lower Missouri/middle Mississippi Valleys
may support an upscale growing cluster or clusters of storms which
could organize sufficiently to support a period or two of strong
surface gusts.

Although the mid-level cold core may tend to remain to the northwest
of the region through the period, cooling aloft across and southeast
of the Front Range, coupled with moistening southeasterly
near-surface flow, may still contribute to favorable thermdodynamic
profiles for a few storms capable of producing severe hail and wind,
in the presence of modest shear late Saturday afternoon and evening.

..Kerr.. 09/17/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Thu Sep 17 07:41:36 2026

ACUS03 KWNS 170740
SWODY3
SPC AC 170739

Day 3 Convective Outlook CORR 1
NWS Storm Prediction Center Norman OK
0239 AM CDT Thu Sep 17 2026

Valid 191200Z - 201200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS SATURDAY INTO
SATURDAY EVENING ACROSS PARTS OF THE MIDDLE MISSISSIPPI VALLEY
THROUGH CENTRAL AND SOUTHERN GREAT PLAINS AND NEAR THE FRONT RANGE
OF THE ROCKIES...

CORRECTED FOR TYPOS

...SUMMARY...
Isolated to widely scattered strong storms posing some risk for
severe wind and hail are possible across parts of the middle
Mississippi Valley into central and southern Great Plains, and east
of the Front Range, Saturday afternoon and evening.

...Discussion...
The stronger westerlies will remain confined to the northern
mid-latitudes, with mid-level troughing forecast to dig across
Hudson Bay, Ontario and Quebec, downstream of broad ridging
overspreading the Canadian Prairies, and in the wake of a
significant cyclone migrating away from the Canadian Maritimes. In
response to these developments, it appears that cool surface ridging
will be maintained to the east of the southern Appalachians, while
the associated high center shifts off the northern Atlantic
Seaboard. Another modest high is forecast to begin shifting across
the central Canadian/U.S. border through much of the northern Great
Plains, Upper Midwest and adjacent upper Great Lakes by late
Saturday night.

This will be preceded by a notable cold front advancing slowly
southward into/across the Ohio and lower Missouri Valleys and
central Great Plains, beneath a weaker belt of westerlies across the
southern mid-latitudes. Within this regime, broad mid-level
troughing is forecast to continue a slow eastward progression across
the Rockies through central Great Plains, downstream of weak
troughing slowly approaching the California coast.

Mid-level ridging downstream of the lead trough will become
increasingly suppressed across the southeastern Great Plains through
lower to middle Mississippi Valley vicinity. A perturbation along
it southeastern periphery may continue slowly west-southwestward
across Florida and the northeastern Gulf Basin.

...Front Range vicinity into middle Mississippi Valley...
Generally warm thermodynamic profiles and modest to weak vertical
shear to the east of the Rockies will continue to limit the severe
weather potential, but isolated to widely scattered strong
thunderstorm development posing at least some risk for severe wind
and/or hail appears possible in a few evolving regimes Saturday into
Saturday night.

Convection with potential to produce strong surface gusts may be
supported by the evolution of a very warm and deeply mixed boundary
layer by late afternoon, within weak pre-frontal surface troughing
across parts of eastern New Mexico, the Texas South Plains and
Panhandle, and northwestern Oklahoma into southeastern Kansas.

Seasonably high moisture content and lift along the low-level
baroclinic zone across the lower Missouri/middle Mississippi Valleys
may support an upscale growing cluster or clusters of storms, which
could organize sufficiently to support a period or two of strong
surface gusts.

Although the mid-level cold core may tend to remain to the northwest
of the region through the period, cooling aloft across and southeast
of the Front Range, coupled with moistening southeasterly
near-surface flow, may still contribute to favorable thermodynamic
profiles for a few storms capable of producing severe hail and wind,
in the presence of modest shear late Saturday afternoon and evening.

..Kerr.. 09/17/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Thu Sep 17 19:26:42 2026

ACUS03 KWNS 171926
SWODY3
SPC AC 171925

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0225 PM CDT Thu Sep 17 2026

Valid 191200Z - 201200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE
SOUTHERN HIGH PLAINS TO THE CORN BELT AND OHIO VALLEY...AND FROM
NORTHEAST COLORADO INTO SOUTHEAST WYOMING...

...SUMMARY...
Occasional wind damage and/or large hail will be possible across
parts of the central High Plains and from the central Plains to the
Ohio Valley.

...Synopsis...
The persistent midlevel ridge over the south central CONUS will
begin to weaken as a midlevel trough moves from ID/UT to WY/CO.
There will be a belt of modestly enhanced midlevel flow from the
central Plains to the Corn Belt/OH Valley, around the northern
periphery of the ridge. This belt of somewhat stronger flow will
coincide with a slow-moving baroclinic zone with richer low-level
moisture into the OH Valley and deeper mixing with hot surface
temperatures along/south of the front across KS/OK/TX. Scattered
thunderstorms are probable along the front, with the strongest
storms expected during the afternoon/evening. Water loaded
downdrafts and up to 30 kt midlevel flow suggests the potential for
occasional downbursts/wind damage across the Corn Belt/OH Valley,
while deeper mixing/inverted-V profiles will favor higher based
storms with occasional strong-severe outflow gusts across the
Plains. Vertical shear within the warm sector will be on the lower
margins for organized severe storms, so this corridor will be
maintained as a MRGL risk.

Wind profiles and forcing for ascent will be a bit stronger across
the central High Plains, downstream from the midlevel trough
approaching the central Rockies. There will be a conditional threat
for a couple of supercells, though uncertainty remains regarding the
magnitude of buoyancy and how much clouds will inhibit surface
heating. Isolated large hail and strong outflow gusts will be
possible, mainly during the afternoon/evening.

..Thompson.. 09/17/2026

$$

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