FOUS11 KWBC 161925
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
225 PM EST Fri Jan 16 2026

Valid 00Z Sat Jan 17 2026 - 00Z Tue Jan 20 2026

...Central and Northern Plains into the Midwest...=20
Days 1 and 3...

With a longwave trough and embedded shortwaves forecast to persist
the next few days, bouts of snow will continue for the Plains to
the Great Lakes/Midwest. Snow squalls along the Arctic front will
yield generally low amounts of snow but potentially
hazardous/dangerous driving conditions. Snow showers and squalls=20
this afternoon will shift southward/eastward tonight through the
Midwest with less coverage. Another shortwave from Canada will
carry another threat for some banded snow showers and some snow=20
squalls Sunday over the Northern Plains to the Upper Midwest/Corn=20
Belt. Snowfall in these potentially lingering/repeating banding=20
could become locally heavy for a time and when combined with the=20
strong winds will create near-zero visibility.=20

Key Messages for these snow squalls are linked at the bottom of=20
this discussion.


...Great Lakes...
Days 1-3...

Persistent cyclonic flow around the Great Lakes will favor rounds=20
of lake effect snow downwind of all Great Lakes Lead system tonight
will favor Michigan (esp. the U.P.) as the surface low moves into=20
Ontario. Next system on Sunday will renew the lake machine across=20
Michigan then into the NY lake belts as the next area of low=20
pressure moves right across Lake Superior into Ontario. WSW flow=20
over Lakes Erie/Ontario could move the bands quite far north (e.g.,
north of BUF and ART) but the progressive flow would vary the band
locations through the period. Three-day snow totals will be=20
modest, with the favored areas (northern shore of the U.P., western
Lower Michigan, and into the Tug Hill) show >50% probabilities for
at least 12 inches of snow.=20


...Ohio Valley, Appalachians, and the Northeast...
Day 1...

Shortwave and cold front out of the Midwest will move into the
Appalachians with generally light to locally modest snow, enhanced=20
over the terrain (western PA/MD and eastern WV) tonight. WPC
probabilities for at least 4 inches of snow are about 20-50%.=20

A strengthening upper jet will move into the Northeast early
Saturday with modest snowfall expanding through the interior
Northeast, especially over the Berkshires and into the southern
Green Mountains just ahead of the cold front. Snow could exceed
1"/hr in areas of the Poconos and northwestern NJ through parts of
the Catskills and into western MA per the 12Z HREF (30-60%=20
chance). The front should clear eastern Maine after 00Z and largely
end most accumulation. WPC probabilities for at least 6 inches of=20
snow are >50% over northwestern MA into southern VT as well as into
the Tug Hill Plateau.


...Southeast, Mid-Atlantic, Northeast...
Days 2-3...

Within the active pattern in the East is a southern portion of the full-latitude trough that swings through the Lower MS Valley=20
Sunday morning. This will bring colder temperatures to the
Southeast as precipitation is slowly moving through the region
along/behind the front. Models have been struggling with how
quickly to move in colder air as precipitation ends, but some light
snow is possible over GA into the Carolinas Sunday morning of a
dusting to a tenth or two.=20

Further up the coast, precipitation will expand northeastward in
the right rear quad of the >160kt jet atop marginal to cold
temperatures (milder along/east of I-95 in the Mid-
Atlantic). Elongated baroclinic zone and areas of surface low=20
pressure will lift northeastward just off the Mid-
Atlantic/Northeast coast Sunday night. Models have struggled here
with the westward QPF extent and are sensitive to the
timing/strength of upstream/incoming mid-level systems as the flow
remains wide open. For now, have remained fairly steady on the
amounts which should result in a swath of a few inches of snow from
the Mid-Atlantic into the NYC area and New England. Highest
probabilities for at least 4 inches of snow are in eastern Maine

50%) as any chance of a more organized system is higher as it=20

approaches Nova Scotia. However, a light snow of 1-3" is likely=20
from NJ northeastward along/east of I-95/91 where WPC probabilities
of at least 2 inches are at least 30%.

Fracasso


...Winter Storm Key Messages are in effect. Please see current=20
Key Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!87Gc6PAfEmAFY1wwwek2esPmSCIZYqVDtFagoGIre7OrO= jq5eIs55aadK1HxyPINNkLRan8wbhzLqIvIYfPQxq8pr0A$=20



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FOUS11 KWBC 170856
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
356 AM EST Sat Jan 17 2026

Valid 12Z Sat Jan 17 2026 - 12Z Tue Jan 20 2026


...Great Lakes...
Days 1-3...

Shortwave trough passages in persistent cyclonic flow through the=20
Great Lakes will favor rounds of lake effect snow for at least the
next week.

A long wave trough over the western Lakes this morning will slowly
shift east through tonight. Northerly flow over Lake Superior will
bring LES to the western U.P. with westerly flow over the L.P.
where Day 1 snow probs for >6" are 40-60% in narrow snow belts.

The next reinforcing trough moves in from the west with NWly flow
bringing more snow to the western U.P. and most of the L.P. western
shore. SWly flow over Lake Erie pushes some single banding into
Buffalo, NY. These areas have Day 2 snow probs for >6" in the
20-60% range. Then the next shortwave trough moves in from the west=20
Monday night with LES until ridging builds briefly late Tuesday.
Day 3 PWPF for >6" is over the eastern U.P. on westerly flow along
with the northern L.P. Most notably however, is single banding in
westerly flow over Lakes Erie and Ontario with Day 3 PWPF for >6"
40-80%.


...Ohio Valley, Appalachians, and the Northeast...
Day 1...

Arctic cold front will shift east from the Midwest this morning and
cross PA this afternoon. Snow squalls could accompany this front
mainly over Ohio and western PA/NY which are highlighted in ongoing
Key Messages that are linked below.=20

A SWly jet stream strengthens in place over the eastern U.S.
through tonight as a very positively-tilted trough shifts down the
Plains and pivots over the Mid-South. Downstream of this trough
will be expanding snow through the interior Northeast, especially=20
over the Poconos, Catskills, Berkshires and southern Green=20
Mountains just ahead of the cold front. Snow could exceed 1"/hr in
these areas per the 00Z HREF. This precip clears eastern Maine=20
this evening. Day 1 WPC probabilities for >4" are 50% in the Mohawk
Valley of NY and over the southern Greens, Whites, and eastern
Maine with 20-30% probs over the Poconos/Catskills, and Berkshires.=20


...Southeast, Mid-Atlantic, Northeast...
Days 2-3...

Within the active pattern in the East is a southern portion of the full-latitude trough that swings through the Lower MS Valley=20
early Sunday. This will bring colder temperatures to the Southeast
as precipitation is slowly moving through the region along/behind=20
the front. Models are in better agreement tonight allowing enough
cold air in before precipitation ends to allow some light snow from
northern FL through the Carolinas Sunday morning with a dusting to
half an inch.=20

Further up the coast, precipitation will expand northeastward in
the right entrance of the >160kt jet atop marginal to cold=20
temperatures (milder along/east of I-95 in the Mid-Atlantic).=20
Elongated baroclinic zone and areas of surface low pressure will=20
lift northeastward just off the Mid-Atlantic/Northeast coast=20
Sunday night. Models have struggled here with the westward QPF=20
extent and are sensitive to the timing/strength of=20
upstream/incoming mid-level systems as the flow remains wide open.=20
For now, have remained fairly steady on the amounts which should=20
result in a swath of a few inches of snow from the Mid-Atlantic=20
into the NYC area and New England. 10 to 20% probs for >4" in Day 2 are
limited to eastern Maine and southeastern New England. The Day 2
swath of >2" over 10% extends south through NJ into the Delmarva.


...Central High Plains...
Days 2/3...

Another Arctic cold front plunges down the Plains tonight through=20
Sunday. This banks cold air over the High Plains/against the front
ranges of the Rockies ahead of a reinforcing shortwave trough that
shifts down the Rockies Sunday night through Monday. Right entrance
jet dynamics over the existing front will allow banded snow to
develop over central MT/WY Sunday night with what appears to be the
main banding early Monday from northern CO terrain through western
KS. The WNWly orientation of these bands is parallel to flow and
should allow for persistence of moderate to locally heavy narrow
bands of snow. As of now Day 2.5 snow probs for >2" are around 20%
along the KS/CO border, but that is likely to increase as the
system gets closer. The ECAIFS was featuring this precip two nights
ago and global physical models are finally catching up. A risk for
4" or more is possible in these persistent banding scenarios.


Jackson



...Winter Storm Key Messages remain in effect and are linked=20
below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!53LqTlmiHMfFGsvloks6bLMMHenjsnI7u8iz2V4YYXMnf= wtJNLrDQZ30xNDPeBw5guoNHsTuPVbwDfbbLJhW__x0xiw$=20



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FOUS11 KWBC 172007
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
307 PM EST Sat Jan 17 2026

Valid 00Z Sun Jan 18 2026 - 00Z Wed Jan 21 2026


...Great Lakes...
Days 1-3...

Shortwave trough passages in persistent cyclonic flow through the=20
Great Lakes will favor rounds of heavy lake effect snow for at=20
least the next week. The Great Lakes are currently mostly ice free
(total ice cover estimated at 15.5% on Jan 16), with surface water
temperatures between 2-6C (warmer over southern Lake Michigan and
Lake Ontario).=20

A long wave trough over Great Lakes tonight will shift east Sunday,
but reinforced by the next trough swinging around the anchored
upper low over the Hudson Bay. For D1, the highest probabilities
(40-70%) for more than 6 inches of snowfall is across the west-
central MI L.P. along the shores of eastern Lake Michigan, where=20
westerly flow and an inverted surface trough are expected to aid in
localized heavy snowfall.

The next reinforcing trough set to bring heavy snowfall during the
D2-D3 period is forecast to move in from the west with NWly flow=20
bringing more snow to the U.P. and most of the L.P. western shore.
Gusty winds up to 40 mph are also expected across the MI U.P,=20
which could lead to additional impacts associated with blowing=20
snow. SWly flow over Lake Erie pushes some single banding into=20
Buffalo, NY on Monday. These areas have Day 2 snow probs for >6"=20
in the 50-80% range. Then the next shortwave trough moves in from=20
the west Monday night with LES until ridging builds briefly late=20
Tuesday into the western Great Lakes. Day 3 PWPF for >6" is over=20
the eastern U.P. Most notably however, is single banding in=20
westerly flow over Lakes Erie and Ontario with Day 3 PWPF for >6"=20
60-90%. For the entire D1-D3 period, probabilities for >12" are
70-90% downwind of Lake Erie and Ontario, including the Buffalo
metro region.


...Southeast, Mid-Atlantic, Northeast...
Days 1-2...

Positively-tilted full-latitude trough this evening will move into
the Mid-South overnight, carrying a surface cold front through the
Southeast. By 12Z Sunday, cold front will be well into the Atlantic
with lagging precipitation over central/southeastern GA just in
advance of the sharp mid-level shortwave. With these cases, even
with surface temperatures just above freezing, dynamic cooling
could easily bring snow to the surface and accumulate via modest
rates 0.5-0.75"/hr per some of the CAM guidance. Though they have
wavered on how things come together, 12z guidance has nudged up
toward supporting a burst of snow over central/southeastern GA
which could accumulate to an inch or so (WPC probabilities of >1"
are around 10% but with upside potential). Light snow from a
dusting to half an inch is possible from the northern FL Panhandle
into upstate SC (>20-30% chance).=20

Further up the coast, precipitation will expand northeastward in=20
the right entrance of the >160kt jet atop marginal to cold=20
temperatures (milder along/east of I-95 in the Mid-Atlantic) and
increasing lower to mid-level FGEN. Elongated baroclinic zone and=20
areas of surface low pressure Sunday morning will coalesce into a
coherent surface low that is forecast to lift northeastward just=20
off the Mid-Atlantic coast to just outside the 40/70 benchmark Sunday
evening. 12Z guidance continued to trend westward with the QPF
axis/edge and have trended up in QPF and thus snow for the
Northeast. This could also keep shoreline temperatures milder for a
time before the low passes by. Snow could fall heavy for a period
over southern/southeastern New England Sunday evening per the 12Z
HREF (20-40% chance of >1"/hr rates). A swath of a few inches of=20
snow is likely from the Mid-Atlantic into the NYC area and New=20
England with upside potential over the terrain (Worcester hills,
etc.). WPC probabilities for at least 4 inches of snow are >50%
over eastern CT through RI and southeastern MA outside the Cape and
Islands. Into Maine, a stripe of a few/several inches of snow is
likely along the coast where probabilities for at least 4 inches of
snow are >40%.=20


...Northern Plains...
Day 1...

**Snow squalls likely across parts of the northern Plains on
Sunday. Key Messages linked at the bottom of the discussion***

The next in a series of arctic cold fronts is forecast to dive
southward across the northern Plains on Sunday, with the greatest
potential for scattered snow squalls along the northern High
Plains. Timing for this front and associated snow squalls/streamers
behind the front starts in eastern MT/western ND during the=20
morning hours and quickly pushes southward into western SD and NE
into the afternoon. Lapse rates per several 12z CAMs near or exceed
6-7C/km for a brief period along the front and SNSQ parameters=20
rise above 4-5 between eastern MT and central NE. These parameters=20
combined with low-to-mid level FGEN intersecting with a healthy=20
100mb wide DGZ should allow for efficient snowfall rates within=20
these showers and bands. Wind gusts up to 60 mph are also possible=20
with this system, adding to the blowing snow potential.

Snow squalls are particularly dangerous for those traveling on
roadways, with extremely low visibilities and slippery conditions
developing rapidly. Be sure to slow down, turn on your lights, and
exit the highway if possible should you get caught in a snow
squall.


...Central High Plains...
Days 2-3...

With cold air banked over the High Plains/against the front ranges
of the Rockies ahead of a reinforcing shortwave trough Sunday=20
night through Monday, conditions will be set for a period of snow
over eastern CO to KS. Right entrance jet dynamics over the=20
existing front will allow banded snow to develop over central MT/WY
Sunday night with what appears to be the main banding early Monday
from northern CO terrain through western KS. The WNWly orientation
of these bands is parallel to the flow and should allow for=20
persistence of moderate to locally heavy narrow bands of snow. As=20
of now WPC probabilities for >2" are 10-20% along the KS/CO=20
border, but that is likely to increase as the system gets closer.=20
QPF trends has been up overall and a risk for 4" or more is=20
possible in these persistent banding scenarios.

Fracasso/Snell/Jackson


...Snow Squall Key Messages are in effect. Please see current Key=20
Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_2.png__;!!DZ3fjg!4O44Oh9C5u6tIlCTliLi6mxu8BcIbKtbjpq7987JV_82b= OrTDGEDnOCpz0-LLQBikF8uV75kXdSRrKcBcTI-CQJ3RK0$=20



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FOUS11 KWBC 180904
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
404 AM EST Sun Jan 18 2026

Valid 12Z Sun Jan 18 2026 - 12Z Wed Jan 21 2026


...Great Lakes...
Days 1-3...

Shortwave trough passages around an anchored deep low over Hudson
Bay maintains cyclonic flow through the Great Lakes with rounds of
heavy lake effect snow through next weekend. The Great Lakes are=20
currently mostly ice free (total ice cover estimated at 14% on Jan=20
17), with surface water temperatures between 2-6C (warmer over=20
southern Lake Michigan and Lake Ontario).

A long wave trough shifts east of the Great Lakes this morning
while the next reinforcing trough swings east across the extent of
the Lakes this afternoon through Monday. NWly flow brings Day 1=20
PWPF for >6" around 50% to the western U.P. (particularly the=20
Porcupine Mtns) and the western shore of the L.P.=20

The flow shifts westerly for Monday shifting the LES focus to the=20
eastern U.P. northern L.P. and for the eastern Great Lakes for=20
Monday with westerly single banding bringing 50-80% probs for >6"=20
to ares south of Buffalo and on the Tug Hill through Watertown.=20

A brief lull in LES sweeps across the Lakes Tuesday, though
single-banding persists on the Eastern Great Lakes. In particular,
the Tug Hill should see notable Day 3 snow with 60% probs for >12".=20


...Southeast, Mid-Atlantic, Northeast...
Day 1...

Positively-tilted full-latitude trough over the Mid-South=20
swing to neutral today as it shifts over the Southeast. Moisture
plume ahead of the trough is mainly rain, but with surface low
pressure developing off the GA coast, the back side of the precip
should turn into moderate bands of snow, particularly from the FL
Panhandle through central GA and the central Carolinas. With these
cases, even with surface temperatures just above freezing, dynamic
cooling could easily bring snow to the surface and accumulate via=20
decent rates of 0.5-0.75"/hr per the 00Z HREF. Day 1 PWPF for >2"
is around 10% in south-central GA and 20% in north-central NC into
southeast VA.

Further up the coast, precipitation will expand northeastward in=20
the right entrance of the >160kt jet atop marginal to cold=20
temperatures (milder along/east of I-95 in the Mid-Atlantic) and
increasing lower to mid-level FGEN. Elongated baroclinic zone and=20
the offshore surface low that rapidly develops as it passes Cape
Hatteras this afternoon and just outside the 40/70 benchmark=20
this evening. The westward extent of the precip shield, where the
snow bands will be is still prominent in 00Z guidance along the
extend of the Mid-Atlantic coast this afternoon and much of New
England late this afternoon through this evening. 00Z HREF mean snow
rates exceed 0.5"/hr over the Delmarva and NJ early this evening
and Long Island/southern New England late this evening through
midnight. Day 1 PWPF for >2" are 40% and up from Philly through
eastern Maine with 50% and up for >4" from NYC through CT/MA/RI and
along the immediate Maine coast. The max for the Day 1 PWPF is from
Providence to Boston where >6" probs are around 60%.=20


...Northern Plains...
Day 1...

**Snow squalls and blizzard conditions likely across parts of the=20
northern Plains today. Key Messages linked below***

The next arctic cold front surges south across the northern Plains
today, with scattered snow squalls mainly this morning from eastern
Montana through the western Dakotas into central Nebraska. The
broad wind field with this front should also trigger blowing snow,
which when combined with additional falling snow could create
blizzard conditions, particularly in the WFO FGF CWA (please see weather.gov/fgf for more info there).=20

Lapse rates reach or exceed 6-7C/km for a brief period along the=20
front and SNSQ parameters rise above 4-5 between eastern MT and=20
central NE. These parameters combined with low-to-mid level FGEN=20 intersecting with a healthy 100mb wide DGZ should allow for=20
efficient snowfall rates within these showers and bands. Wind gusts
up to 60 mph are also possible with this system, adding to the=20
blowing snow potential.

Snow squalls are particularly dangerous for those traveling on
roadways, with extremely low visibilities and slippery conditions
developing rapidly. Be sure to slow down, turn on your lights, and
exit the highway if possible should you get caught in a snow
squall.


...Central High Plains...
Days 1-2...

Cold air surges over the High Plains/against the front ranges of=20
the Rockies today ahead of a reinforcing shortwave trough that
shifts south over the Rockies tonight through Monday. Right=20
entrance jet dynamics over the front will allow banded snow to=20
develop over central MT/WY this evening with stronger banding=20
overnight from northern CO terrain through western KS with snow
bands lingering Monday morning over southwest KS into western OK.=20
The WNWly orientation of these bands is parallel to the flow and=20
should allow for persistence of narrow bands of moderate to=20
locally heavy snow. Day 1 PWPF for >2" remain limited to 30% over=20
the CO Front Range and east of the Palmer Divide in CO/western KS.
CAMs generally struggled with these synoptically driven bands that
have a risk for high performance given the motion along
orientation, so there remains a threat for 4"+ in persistent=20
banding scenarios.

Jackson



...Winter Storm Key Messages are in effect. Please see current=20
Key Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_2.png__;!!DZ3fjg!8mgHyoidHlr2hQD8QC6_PkFw3gcML7nZY0LgmJfp3PNA_= 50yuIFMLCOpfSkQNcKumw5V4v5BVTNpxp0ITTZIl5fYnzo$=20



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FOUS11 KWBC 181903
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
203 PM EST Sun Jan 18 2026

Valid 00Z Mon Jan 19 2026 - 00Z Thu Jan 22 2026


...Great Lakes...
Days 1-3...

Shortwave trough passages around an anchored deep low over Hudson
Bay maintains cyclonic flow through the Great Lakes with rounds of
heavy lake effect snow through at least the first part of the week.
The Great Lakes are currently mostly ice free (total ice cover
estimated at 14%), with surface water temperatures between 2-6C
(warmer over southern Lake Michigan and Lake Ontario). 850mb
temperatures of -20C or so will be quite sufficient for a delta T.

The next reinforcing trough swings east across the extent of the
Lakes tonight/tomorrow along with a surface front. Post-FROPA NW
flow through early Tuesday will promote multi-banded snow into the
U.P. and western Lower Michigan where WPC probabilities for at
least 6 inches of snow through 12Z Tue are >70%. For Lakes
Erie/Ontario, SW flow ahead of the system tonight will keep the
bands mostly in Canada except for around Buffalo/Niagara Falls
before sinking back southward Monday afternoon/evening and
eventually waning on Tuesday (lastly over the Tug Hill). WPC
probabilities for at least 6 inches of snow through 00Z Wed are

90% over the Tug Hill and near/just south of Buffalo. Over the Tug

Hill where the band could persist the longest, WPC probabilities
for at least 18 inches of snow are >50%.

After a brief lull Tuesday evening in the western Lakes, another
system will move through the region overnight and into Wednesday
with the surface low lifting from the Corn Belt across Lake
Michigan through Lower Michigan. Synoptic snow will be followed by
lake effect snow on Wednesday with the highest probabilities for at
least 4 inches of snow over western Lower Michigan near the track
of the area of low pressure (>60% probs).


...Eastern New England...
Day 1...

Deepening area of low pressure just outside the 40/70 benchmark at
00Z tonight will lift quickly northeastward into Atlantic Canada
overnight. Light to modest snow and snow rates (near 1"/hr) atop
cold to marginal surface temperatures over southeastern and eastern
New England will continue snow through the early overnight hours
before winding down by 12Z Monday. WPC probabilities for an
additional 4 inches of snow after 00Z are >50% over eastern MA and
northern RI (except for the Cape and Islands) and along eastern
coastal Maine.


...Central High Plains...
Day 1...

Arctic front diving through the Plains will bring in colder air to
the High Plains tonight. Right entrance jet dynamics over the
front will allow banded snow to develop over central MT/WY this
evening with stronger banding overnight from northern CO terrain
through western KS with snow bands lingering Monday morning over
southwest KS into western OK. The WNWly orientation of these bands
is parallel to the flow and should allow for persistence of narrow
bands of moderate to locally heavy snow. Day 1 PWPF for >2" remain
limited to 30% over the CO Front Range and 10-20% east of the
Palmer Divide in CO/western KS. CAMs generally struggled with these synoptically driven bands that have a risk for high performance
given the motion along orientation, so there remains a threat for
4"+ in persistent banding scenarios (e.g., NAM nest).

Fracasso


$$

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FOUS11 KWBC 190842
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
342 AM EST Mon Jan 19 2026

Valid 12Z Mon Jan 19 2026 - 12Z Thu Jan 22 2026


...Great Lakes/Upper Midwest...
Days 1-3...

Shortwave trough passages around a deep low over anchored over
Hudson Bay maintain cyclonic flow and Lake Effect Snow across the
Great Lakes snow belts at least into this weekend. The Great Lakes
are ice free away from the narrower bays. 850mb temperatures of
-20C to -25C over surface water temperatures between +2 to 6C will
continue to make for a high delta T and convective development.

A reinforcing trough currently over the U.P. swings east across
the rest of the Lakes today with a leading arctic cold front.
Post- FROPA NW flow through early Tuesday will promote multi-
banded snow into the U.P. and northern Lower Michigan where Day 1
WPC probabilities for >6" are 40-70%.

For Lakes Erie/Ontario, SWly flow veers Wly today with ongoing
single-band LES shifting south of Buffalo and onto the Tug Hill
Plateau. Day 1 PWPF for >6" are 60-80% in these zones. LES
continues through Tuesday night, so Day 2 PWPF for >6" are
especially highlighted over the Tug Hill with values over 80%.

A brief lull occurs Tuesday evening in the western Lakes under
brief ridging until the next shortwave/a clipper system shifts east
through the region Tuesday night through Wednesday. A surface low
lifts from Iowa across the L.P. through that time with synoptic
snow bands across northern Iowa and southern Wisconsin where Day
2.5 snow probs for >4" have risen to 20%. Brief LES can be expected
Wednesday into Wednesday night where Day 3 PWPF for >4" are 40-70%
in the western U.P., the length of the western L.P. shore, and east
of Lakes Erie and Ontario.

Yet another clipper is quick on the heels on a similar path to the
previous with snow bands likely over northern Iowa, southern
Wisconsin and souther Michigan again Wednesday night.


...Central High Plains...
Day 1...

Right entrance jet dynamics continue to provide lift over a
baroclinic zone on the central High Plains as high pressure builds
south over the Northern Plains. A decent swath of snow with narrow
embedded bands of moderate to locally heavy snow have developed
from northern CO Front Range to western KS. These will persist into
or through the morning as should slowly sag south to southwestern
KS as the jet also shifts south with the shortwave trough pushing
down the Rockies. An additional few inches can be expected in the
better bands.


The probability of significant icing is less than 10 percent.


Jackson




$$

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FOUS11 KWBC 192055
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
355 PM EST Mon Jan 19 2026

Valid 00Z Tue Jan 20 2026 - 00Z Fri Jan 23 2026


...Great Lakes/Upper Midwest...
Days 1-3...

A highly negative AO teleconnection will keep the large Hudson Bay
vortex in place while embedded shortwave troughs revolving around
the Hudson Bay vortex continue to trigger LES bands over the
typical snow belts. The Great Lakes are remain ice free away from
the narrower bays and coast lines. Sufficiently steep lapse rates
persist due to 850mb temperatures of -20C to -25C racing over
surface water temperatures between +2C to +6C.

For Lakes Erie/Ontario, SWly flow veers Wly today and tonight with
ongoing single-band LES shifting south of Buffalo and onto the Tug
Hill Plateau. Day 1 PWPF for >6" are 70-90% in these zones.

A brief lull occurs Tuesday evening in the western Lakes and
eventually eastern Lakes by Wednesday morning under brief ridging
until the next shortwave/a clipper system shifts east through the
region Tuesday night through Wednesday. A surface low lifts from
Iowa across the L.P. through that time with synoptic snow bands
across northern Iowa and southern Wisconsin where Day 2 snow probs
for >4" are 10-20%. Brief LES can be expected Wednesday into
Wednesday night where Day 2.5-3 PWPF for >4" are 40-70% in the
western U.P., the length of the western L.P. shore, and east of
Lakes Erie and Ontario.

Yet another clipper is quick on the heels on a similar path to the
previous with snow bands likely over northern Iowa, southern
Wisconsin and souther Michigan again Wednesday night through
Thursday. In total through Thursday, snowfall amounts are expected
to add up to at least 1 to 2 feet downwind of Lake Erie and Lake
Ontario, with higher chances (60-80%) for over 2 feet across the
Tug Hill of NY.


The probability of significant icing is less than 10 percent.


Snell/Jackson



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FOUS11 KWBC 200909
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
409 AM EST Tue Jan 20 2026

Valid 12Z Tue Jan 20 2026 - 12Z Fri Jan 23 2026


...Northern Plains, Upper Midwest, Great Lakes...=20
Days 1-3...

Sprawling Hudson Bay vortex dominates the continental pattern
through this week. A pair of shortwave troughs round the low,=20
emerging from the Canadian Prairies as clippers and cross the=20
Northern Plains/Upper Midwest and the Great Lakes today and=20
Wednesday. These clippers will continue to trigger LES bands over=20
the typical snow belts in their wake.=20

The first shortwave trough axis reaches Montana this morning with
repeating areas of moderate snow through the morning with
topographical enhancements where 1"/hr snow rates are possible. Day
1 PWPF for >4" are around 50% on the Little Belt and Big Snowy
Mtns.

This clipper will redevelop snow bands over eastern SD this
afternoon with a decent, but narrow swath of snow then east along
the MN/IA and WI/IL borders tonight and southern MI late tonight
into Wednesday. Day 1.5 PWPF for >4" is 40-50% from northeast IA
along the WI/IL border and southwest MI. The Wednesday clipper
should follow a similar track, but with lower overall precip.

The Great Lakes ice coverage is rising, currently around 18%=20
mainly on narrower bays and western Lake Erie per GLERL.=20
Sufficiently steep low level lapse rates persist with 850mb=20
temperatures of -20C to -25C over surface water temperatures=20
between +1C and +5C.

Westerly flow continues today ahead of the first clipper with a
lull spreading east tonight through Wednesday night as the two
clippers cross. The strong single-banding persists from Lake
Ontario today with Day 1 PWPF for >8" additional after 12Z over 80%
in the Tug Hill Plateau. Day 2 PWPF for >6" is around 30% east of
Lake Erie and around 50% in the Tug Hill. Then LES resumes for the
northern Lakes with Day 3 PWPF for >6" over 90% in the Tug Hill.


...Southern Tier...
Starting Day 3...

Southern stream low pressure pushes inland over the northern Baja
California Friday with broad cyclonic flow out ahead which opens up
Gulf moisture to surge over Arctic-sourced air spilling down the
Plains from the Hudson Bay vortex. Broad areas of heavy wintry
precip are expected to develop on Friday over Texas to the
Southeast. Confidence is high for this event occurring though
details on how much winter accumulations, types, and locations have
uncertainty mainly derived from the timing of the southern stream
wave surging inland. Key Messages on this storm and the extreme
cold are active and linked below.=20



Jackson



...Extreme Cold Key Messages and Southern Tier Winter Storm Key=20
Messages are linked below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!66kif1vnRkDxDwdhyvRANP2JpfKbLwHYpkGOMDg3cQ-gJ= 5bEtdquSKelv5Dvb_Uca9AqyUzAP2URkWO8nhNKhH_ybR0$=20

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_2.png__;!!DZ3fjg!66kif1vnRkDxDwdhyvRANP2JpfKbLwHYpkGOMDg3cQ-gJ= 5bEtdquSKelv5Dvb_Uca9AqyUzAP2URkWO8nhNKUKiHd1s$=20



$$

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FOUS11 KWBC 202058
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
358 PM EST Tue Jan 20 2026

Valid 00Z Wed Jan 21 2026 - 00Z Sat Jan 24 2026


...Northern Plains, Upper Midwest, Great Lakes...=20
Days 1-3...

Sprawling Hudson Bay vortex dominates the continental pattern
through this week. Within the broad cyclonic pattern, a shortwave=20
and developing surface wave is forecast to traverse the Upper=20
Midwest tonight. Tonight, a corridor of warm advection and=20
associated 850-700 mb frontogenesis on the northeast flank of the
low center will drive an east-west oriented snow band spreading=20
from the Northern Plains into the Upper Midwest. The latest PWPF
for >4" is 20-30% over northwest IA and southern WI, which=20
increases to 50-75% over southwestern MI. By tomorrow, a modest
clipper system following behind the lead wave will drive additional
snowfall, although the QPF footprint with this system is markedly
lower. Meanwhile, strong single-banding will gradually come to an=20
end tonight downwind of Lake Ontario. Even so, the Day 1 PWPF for=20

6" is around 50% in the Tug Hill Plateau, which ramps up to above=20

90% by Day 3 with the approach of a strong Arctic high from the=20
west.

Asherman/Jackson

...Southern Plains to Lower MS Valley...
Day 3...

....Major Winter Storm To Begin Impacting the South Central U.S.=20
on Friday...

The highly anticipated winter storm that is expected to impact much
of the southern and eastern U.S. this weekend begins on Friday. To
produce a winter storm of this size and magnitude, the weather
pattern must have a very cold air-mass anchored to the north. In
this case, a near record-breaking dome of high pressure to the
north is filtering in a frigid air-mass throughout much of the
eastern two-thirds of the CONUS. Meanwhile, an upper trough off the
California coast will direct subtropical East Pacific moisture at
the Southern Plains. Persistent Pacific moisture overrunning an
arctic air-mass will result in not only snow, but treacherous sleet
and freezing rain from southern Texas to the Lower MS Valley.=20
Exact placement of the wintry mix zone remains unclear as guidance=20
is adjusting how strong the WAA aloft will be, but confidence is=20
growing in Friday morning being the starting point for wintry=20
precipitation. The latest WSO through Friday afternoon (D4 WSO=20
shows a large footprint of >50% odds for a warning-level snowfall=20
event from the TX Panhandle on east through much of OK and into=20
central AR. Farther south, heavy sleet and hazardous freezing rain=20
will be more common in the heart of Texas on east to the ArkLaTex.=20
This storm will have wide reaching impacts through the Mid-South=20
and all the way to the East Coast by this weekend. Residents=20
affected by this storm should continue to monitor the forecast=20
through their local warning forecast office at weather.gov.=20


Mullinax



...Winter Storm Key Messages are in effect. Please see current=20
Key Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!97DbUNAoUxdcCZ0op6hRdmQMMIqdMz9bPUdDmexpzgKBo= UoyobGpTezL1K6VO3Vj0OtgEnw3C8SsVqJqr9URmM_gz14$=20

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_2.png__;!!DZ3fjg!97DbUNAoUxdcCZ0op6hRdmQMMIqdMz9bPUdDmexpzgKBo= UoyobGpTezL1K6VO3Vj0OtgEnw3C8SsVqJqr9UR0mK2zF8$=20



$$

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FOUS11 KWBC 210923
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
423 AM EST Wed Jan 21 2026

Valid 12Z Wed Jan 21 2026 - 12Z Sat Jan 24 2026


***At Least Major Winter Storm Impacts The South Friday Through=20
This Weekend, Expanding Up The East Coast Saturday Night***

...Southern Rockies, Southern Plains, Through the Mid-South and
Gulf Coast into The Tennessee Valley...=20
Days 2-3...

Precip onset for major winter storm Friday on the Southern Plains=20
and Southern Rockies, quickly intensifying and expanding east over
the Mid-South and Gulf Coast states into the Tennessee Valley=20
Saturday. Expansive cold air mass spills down the Plains Thursday=20
night from 1052mb high pushing into North Dakota. Meanwhile, a=20
cutoff low under a deep ridge off the West Coast approaching=20
southern CA Thursday gets absorbed into the flow of a northern=20
stream trough dropping down the northern Rockies Friday making the=20
united trough full-latitude (through the length of the CONUS) by=20
Saturday. Subtropical East Pacific moisture ahead of the low trough
will spread across northern Mexico with Gulf moisture surging=20
north as early as Thursday night. Persistent Pacific and Gulf=20
moisture overrunning the arctic-sourced airmass will result the=20
full wintry p-type scenario from plain rain near the Gulf Coast to=20
freezing rain not too far inland, to sleet north of that and=20
finally snow where the warm nose remains subzero. The main notes=20
for the 00Z cycle is a northward shift in both QPF and the thermal=20 profiles/warm nose. However, the surface cold air should continue=20
to progress so in a sense the broadness of the winter weather swath
is still expanding (stretching from the Gulf Coast to the central=20
Plains). The precip intensification Friday night through Saturday=20
will be remarkable over the southern Plains and Mid-South with=20
heavy rates and likely catastrophic impacts for at least local=20
scales given the risk for over an inch of ice accretion and deep=20
snow with heavy sleet in between. Residents should prepare for=20
prolonged power outages that occur during the coldest air of the=20
season. Please monitor the forecast for your area via weather.gov.=20
With so much heavy precip occurring just after the WWD time range=20
ending 12Z Saturday, probabilities will be presented through 00Z=20
Sunday (Day 3.5). Day 3.5 PWPF for > 8" is 50-80% across much of=20
the central/southern CO Rockies through the central NM ranges with=20
a wide swath of 20-50% from much of OK, northern AR along the TN/KY
border to the southern Appalachians. Day 3.5 PWPF for >0.5" is=20
20-50% from northeast TX across the LA/AR border and northern MS=20
and northwest AL.=20


...Great Lakes...=20
Days 1-3...

Sprawling Hudson Bay vortex dominates the continental pattern
through this week. Within the broad cyclonic pattern, a pair of=20 shortwaves/clippers cross the Great Lakes through tonight with=20
associated 850-700 mb frontogenesis driving east-west oriented=20
snow bands over WI again and the Great Lakes. Day 1 PWPF for >4"=20
is 50% over southwest MI, northwest PA/western NY and over the Tug
Hill and Mohawk Valley. Northern lake LES continues then through
Friday. Day 2 PWPF for >4" is 50-80% for the Keweenaw and eastern=20
U.P., northern L.P., and the Tug Hill to the western Adirondacks.=20
These values diminish Saturday under surface ridging under the core
of the Arctic cold.


Jackson


...Winter Storm Key Messages remain in effect for extreme cold and
a major winter storm for the south. They are linked below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!6TkyJsUVAAqGEjMXf63mjHBuW427QXBU54gcPNA4JaazV= CZVSrgAWf2a7OjMjHN5lztAe-3wWz8lG44mcV-Fe50kOA0$=20

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_2.png__;!!DZ3fjg!6TkyJsUVAAqGEjMXf63mjHBuW427QXBU54gcPNA4JaazV= CZVSrgAWf2a7OjMjHN5lztAe-3wWz8lG44mcV-F-DbOOYI$=20



$$

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FOUS11 KWBC 212105
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
405 PM EST Wed Jan 21 2026

Valid 00Z Thu Jan 22 2026 - 00Z Sun Jan 25 2026


***Major Winter Storm To Bring Significant Impacts To The South
Friday Through This Weekend, Expanding Up The East Coast Saturday
Night Into Sunday***

...Southern Rockies, Southern Plains, Gulf Coast, Mid-South,
Southern & Central Appalachians, & Mid-Atlantic...
Days 2-3...

The ingredients for the impending major winter storm begin to take
shape Thursday night. A broad upper trough located off Baja
California will work in tandem with a ridge axis near Mexico to
direct a rich plume of tropical East Pacific moisture into the
Southern Rockies and Plains. At the same time, an arctic front
ushers in the coldest temperatures this season across the Great=20
Plains with a highly anomalous dome of arctic high pressure=20
building in over the North Central U.S.. As high pressure rushes=20
south, easterly upslope flow induced between the high pressure to=20
the north and lower pressure near California will cause upslope=20
flow into the higher terrain of the CO and NM Rockies with lighter=20
snowfall in the central High Plains. WPC probabilities show high=20
chances (>70%) for snowfall above 9,000ft in the CO/NM Rockies=20
through Saturday afternoon.

Precipitation will blossom over much of KS, OK, and TX Friday, starting
as rain across much of TX initially, but look for precipitation to
transition to snow over KS, northern OK, and the TX Panhandle by=20
Friday afternoon and evening. Farther south, strengthening low-=20
level WAA will over-run the incoming sub-freezing layer in the=20
lowest 2,000ft of the atmosphere from West Texas to as far east as=20
the Mid-South. Sleet will become more prevalent over the Red River=20
Valley, north-central AR, and into western TN, while freezing rain
is the primary preip type from the TX Hill Country through the=20
ArkLaTex and as far east as the TN Valley. Heavy sleet is possible
in some of these areas with multiple inches of sleet possible
through Saturday. The slow progression of the upper trough over=20
Baja California and the bitterly cold arctic air-mass anchored=20
over the eastern two-thirds of the CONUS is a recipe ripe for=20
prolonged freezing rain from central TX to as far east as the=20
southern Appalachians through 00Z Sunday. WPC probabilities show=20 concerningly high probabilities (50-70%) for ice accumulations=20
through 00Z Sunday over one-quarter inch. The areas of greatest=20
concern are over the ArkLaTx, southern AR, northern LA, northern=20
MS/AL, and southern TN where low-to-moderate chances (30-50%)=20
exist for over one-half inch of ice. While this discussion is=20
geared to the short term (ending 00Z Sunday) the ice in all these=20
areas are forecast to continue through Saturday night and even into
Sunday. There is great concern for extensive tree damage and power
outages from central TX on east through the Mid-South and into the
Southern Appalachians into Sunday.

Farther north, the air-mass through the depth of the atmospheric
column remains cold enough to support all snow from the Central
Plains on east through the Ozarks and across northern TN and much
of KY beginning Friday evening in the Plains, then into the TN/OH
Valleys Saturday morning. By midday and into Saturday afternoon,
periods of snow will reach the southern and central Appalachians
and potentially the VA/NC Piedmont. Snowfall rates topping 1"/hr=20
are likely in areas just north of the strongest 850-700mb FGEN=20
zone and vertical velocities are highest in a highly saturated=20
dendritic growth zone in the Central Plains and OH Valley. The=20
very cold temperatures over KS on east through MS and into the OH=20
Valley will cause SLRs to range anywhere from between 12-18:1 with=20
the higher SLRs over KS. WPC probabilities through 00Z Sunday=20
depict high chances (>70%) for >4" of snow over central and=20
southern KS, much of northern OK, the TX Panhandle, and into the=20
Ozarks of northern AR and southern MO. The best chances for >8" of=20
snowfall reside over the Ozarks where moderate chance probabilities
(40-60%) are present.=20

Similar to the ice, the snow will by no means be over given the=20
extensive plume of anomalous moisture emanating out of the East=20
Pacific. By Saturday night, southerly flow out of the Gulf will=20
continue to direct copious amounts of moisture into the eastern
U.S., resulting in a highly disruptive and dangerous winter storm
from the Mid-South to the Mid-Atlantic. WPC continues to issue Key
Messages for this winter storm and a link to them can be found
below.


...Great Lakes...=20
Days 1-3...

A Hudson Bay vortex pivoting south through Ontario will sustain the
seemingly endless cyclonic flow over the Great Lakes and their
usual snow belts. 500mb heights associated with this powerful upper
low are quite anomalous (below the 1st climatological percentile
in southern Ontario Thursday into Friday night). WPC probabilities
highlight high chances (>70%) for snowfall totals >4" over the
northern tier of the U.P., western MI, along the Chautauqua Ridge
on north into western NY, and down wind of Lake Ontario over the
Tug Hill. The Tug Hill most notably will continue to receive very
heavy snow over the next few days highlighted by WPC 72-hour
probabilities sporting high chances (>70%) in the Tug Hill. A
growing concern is for snow squalls over the Northeast. WPC
initiated Key Messages for what appear to be multiple rounds of
snow squalls from western NY on east through New England, with=20
some squalls possible as far south as northern PA. The final round
of squalls are expected on Friday as an arctic front traverses the
region, causing steep lapse rates and focused vertical ascent. For
more details on the snow squall threat in the Northeast through
Friday, please refer to our Key Messages.


Mullinax



...Winter Storm Key Messages are in effect. Please see current=20
Key Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!4leUoWpjIV7yE2h8DceGN34RPg1d4yvNkmbTFjbw31Qzn= tpehh7jECz3HdwJRagEcw4-6zFuFEKoWCJC7xOHFH7tjJY$=20

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_2.png__;!!DZ3fjg!4leUoWpjIV7yE2h8DceGN34RPg1d4yvNkmbTFjbw31Qzn= tpehh7jECz3HdwJRagEcw4-6zFuFEKoWCJC7xOHAW-kv9A$=20

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_3.png__;!!DZ3fjg!4leUoWpjIV7yE2h8DceGN34RPg1d4yvNkmbTFjbw31Qzn= tpehh7jECz3HdwJRagEcw4-6zFuFEKoWCJC7xOHnzl7X1Y$=20



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FOUS11 KWBC 220845
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
345 AM EST Thu Jan 22 2026

Valid 12Z Thu Jan 22 2026 - 12Z Sun Jan 25 2026


***Significant Winter Storm To Bring Potentially Crippling Impacts
To Parts Of The South Friday Through This Weekend, Expanding Up=20
The East Coast Saturday Night Into Sunday***

...Southern Rockies and Southern Plains through the Ohio/Tennessee
Valleys into the Mid-Atlantic...
Days 2-3...

Estimated over 130 million residents under winter weather headlines
this morning as confidence continues to increase on a highly=20
impactful and extremely wide- reaching winter storm to begin on=20
Friday across the south-central U.S., eventually pushing towards=20
the East Coast by Saturday night into Sunday. Guidance has nearly=20 unanimously converged on the upper low churning just west of=20
southern CA (sampled by recon aircraft for the recent 00z model=20
suite) to eject eastward ahead of a diving northern stream=20
shortwave and fully phase by the day 4 timeframe. Uncertainty=20
remains associated with the speed of the approaching northern=20
stream trough, which eventually leads to the amplified pattern in=20
the central/eastern U.S.. However, this uncertainty has decreased=20
tonight as guidance converges on cluster 1 from WPC's 12z 1/21=20
clusters. Some guidance remains more amped (CMC/ECMWF) than others=20
(GFS) and leads to some lingering uncertainty regarding the=20
northern extent of heavy QPF and the mid- level warm nose. However,
all scenarios now point to a large QPF footprint falling in the=20
form of frozen precipitation and resulting in a significant winter
storm.

The aforementioned southern CA upper low will help surge ample=20
Pacific moisture (above the 90th climatological percentile per the=20
12z NAEFS) into the southern U.S. by Friday night, where a deep=20
arctic airmass is placed in ideal position for overrunning and=20
wintry precipitation. This arctic airmass in place is brought to=20
the region by a near record 1050mb surface high pressure over the=20
Northern Plains on Friday. As time progresses this high pressure is
expected to moderate and evolve into more of a "banana" look,=20
which is classic for heavy winter precipitation in the East as
low-levl cold air continues to sink southward towards a stationary
front forecast to stretch along the Gulf Coast. A few weak areas of
low pressure are forecast to form along this front before gradually
lifting northward into the TN Valley and along the Carolina=20
coastline by the end of D3. Decided to split up the remainder of=20
the discussion into hazard- type categories given this event covers
such a massive amount of real- estate. For local forecasts and=20
more details, read your local WFOs AFD.

Heavy Freezing Rain/Sleet...
Arguably the most lasting impact associated with this winter storm
could be from heavy accumulating freezing rain and sleet=20
stretching from the southern Plains, Mid-South, Tennessee Valley,=20
and southern Mid- Atlantic. This is due to very cold low-level=20
arctic air being reinforced by the strong high over the north-=20
central U.S. and a warm nose aloft (at around 750mb per cross=20
section model soundings) melting snow as it falls through the=20
column before refreezing just before or at the surface. The=20
greatest freezing rain amounts and impacts are currently forecast=20
across northeast TX through northern MS as favorable thermal=20
profiles linger for over 24 hours beginning Friday night. WPC=20
72-hour probabilities for >0.5" of freezing rain are high >70%=20
across southern AR into parts of northwest MS. Here, ice accretion=20
could be crippling and exceed 0.75-1.00", which would very likely=20
lead to widespread long- lasting damage to infrastructure,=20
including power outages and tree damage. Major sleet accumulations
are also likely just north of the freezing rain area stretching=20
from southern OK/north TX through central AR and into the Mid-
South, with more than a few inches of sleet possible. This could=20
make for treacherous driving conditions and lasting travel impacts=20
due to the bitterly cold airmass expected to linger into next week=20
over the region.

Heavy icing is also likely into the TN Valley and nearby southern=20 Appalachians and Mid- Atlantic, where freezing rain continues=20
beyond the D3 timeframe. The setup across the southern Mid-Atlantic
down as far south as northern GA and areas just inland from the=20
coasts of the Carolinas is an extreme case of CAD with a 1040mb=20
high situated over the Interior Northeast on Saturday night. This=20
high pressure filters very low/dry dew points with values below
zero prior to precip onset late Saturday. This cold air wedge
remains sharply locked in place at the surface for the remainder=20
of the event as 700-850mb temperatures begin to increase well above
freezing by the end of D3 throughout the Carolinas and northern=20
GA. WPC probabilities for >0.25" of freezing rain accretion through
12z Sun. are currently 40-70% from northern AL/TN through northern
GA and into the Midlands of SC and areas just inland of the NC=20
Tidewater region. Heavy sleet accumulations are also possible where
the low-level column remains colder into VA Piedmont.

Heavy Snow...
North of the mixed precipitation area and closely tide to both a=20
favorable LFQ of a zonally oriented 180kt upper jet and strong=20
700mb fgen, snow is the primary precipitation type stretching from=20
the southern High Plains of east-central NM and the southern=20
Rockies through the Plains, Mid-Mississippi Valley, Ohio Valley,=20
and Mid-Atlantic by Sunday morning. Favorable upslope flow as the=20
strong arctic high pressure noses southward along the High Plains=20
starts on Friday across the southern Rockies, with light snow and=20
even a chance for freezing drizzle at onset across the central=20
Plains until the column fully saturates. Heavy snow is then=20
forecast to begin breaking out Friday night from the=20
central/southern Plains through the mid-Mississippi Valley and=20
spanning much of the Ohio Valley and parts of the Midwest on=20
Saturday. Snowfall rates could near 1"/hr as strong lift intersects
with a region about 150 miles north of the mixed precip zone where=20
the DGZ is forecast to be extremely deep (about 500 mb per areal=20
average soundings). This would allow for efficient formation of=20
dendrites where ample lift can fully moisture the column. Should a=20
region remain in this zone for a longer enough period it's not out=20
of the realm of possibility 30:1 snow ratios are observed.=20
However, most locations appears to progressively see this favorable
DGZ move east-northeast with time and shrink as mid-level=20
temperatures increase above -8C and allows for more needles than=20
dendrites. WPC probabilities for >6" of snow through 12z Sun. are=20
medium to high (30-70%) stretching from east-central NM and the TX=20
Panhandle across northern OK, into the Mid-Mississippi Valley.=20
These probabilities increase to above 70% in the Ohio Valley,=20
where 8-10" of snow is possible. The widespread nature of this
heavy snow is likely to significantly impact both ground and air
travel in the region.

One area that is slowly becoming the most favorable location for=20
heavy snowfall rates and potentially the most impressive snowfall=20
amounts is the central Appalachians, northern VA, MD, and southern=20
PA through early Sunday. As the upper level trough deepens over the
central U.S. Saturday night, mid- level flow begins to increase=20
out ahead of it and meets the mid-level warm front stretching from
the eastern Ohio Valley into the Mid- Atlantic. Several 00z models
highlight increasing 700mb fgen over the eastern Ohio Valley and=20
into central VA by late D3, which supports the potential for an=20
extended period of 1"/hr rates across much of eastern WV,=20
central/northern VA, MD, and southern PA. The 0C warm nose may=20
begin to approach northern VA by the end of D3, but areas just to=20
the north could see 6-12" by sunrise on Sunday as precipitation=20
lingering further into the day on Sunday. Snow ratios will also be
favorable at onset and could potentially exceed 20:1 within
enhanced banding, which is well above the 11:1 climatology in the
region. Current WPC probabilities through D3 are medium to high=20
(40-70%) for at least 8" of snow, this includes areas just west of=20
I-95 from D.C. to Baltimore. Heavy snow is expected to continue=20
stretching into the Northeast and New England on Sunday, see WPC's=20
Extended Forecast Discussion for more. Also, see the Key Messages=20
linked at the bottom of this discussion.


...Great Lakes...=20
Days 1-2...

A Hudson Bay vortex pivoting south through Ontario will sustain the
seemingly endless cyclonic flow over the Great Lakes and their
usual snow belts before strong high pressure builds overhead on D3
and ends this lake effect pattern for the time being. 500mb=20
heights associated with this powerful upper low are quite anomalous
(below the 1st climatological percentile per 12z NAEFS in southern
Ontario Thursday into Friday night). WPC probabilities highlight=20
medium-high chances (>60%) for snowfall totals >6" over the=20
northern tier of the U.P., along the Chautauqua Ridge on north=20
into western NY, and down wind of Lake Ontario over the Tug Hill.=20
The Tug Hill most notably will continue to receive very heavy snow=20
over the next few days highlighted by WPC 48-hour probabilities=20
sporting high chances (>70%) for >8" in the Tug Hill.=20

A growing concern is for snow squalls over the Northeast. WPC=20
initiated Key Messages for what appear to be multiple rounds of=20
snow squalls from western NY on east through New England, with some
squalls possible as far south as northern PA early today. This is
highlighted well in CAMs snow squall parameter, with highest
potential on Thursday from western PA through central NY. The=20
final round of squalls are expected on Friday as an arctic front=20
traverses the region, causing steep lapse rates and focused=20
vertical ascent. This front will also usher dangerously cold
temperatures and wind chills. For more details on the snow squall=20
threat in the Northeast through Friday, please refer to our Key=20
Messages.


Snell




...Winter Storm/Snow Squall/Extreme Cold Key Messages are in=20
effect. Please see current Key Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!4SOx9iXiM3PgwTKiPMC2-PfsGt8BJz0BBMMz9h4kUUIjD= IQTQvpLmpBzti1jhxxLn8WLhLWkb5WyZSxjoet_GDZdtno$=20

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_2.png__;!!DZ3fjg!4SOx9iXiM3PgwTKiPMC2-PfsGt8BJz0BBMMz9h4kUUIjD= IQTQvpLmpBzti1jhxxLn8WLhLWkb5WyZSxjoet_AHZ3rCs$=20

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_3.png__;!!DZ3fjg!4SOx9iXiM3PgwTKiPMC2-PfsGt8BJz0BBMMz9h4kUUIjD= IQTQvpLmpBzti1jhxxLn8WLhLWkb5WyZSxjoet_3CqF82U$=20



$$

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FOUS11 KWBC 221959
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
259 PM EST Thu Jan 22 2026

Valid 00Z Fri Jan 23 2026 - 00Z Mon Jan 26 2026


...Major winter storm to bring the potential for crippling icing,=20 significant sleet, and heavy snow from the Southern Plains through=20
the Southeast and up the Atlantic Coast into New England...

The event will begin Friday morning across the Southern Plains. The
driver of this event is an impressive overlap of intensifying
synoptic ascent with increasing subtropical moisture.=20

The synoptic pattern becomes favorable Friday in response to the
evolution of multiple shortwaves rotating through an amplifying
trough across the eastern CONUS. A closed 500mb low off the Baja
Peninsula will begin to open and shear to the east, at the same
time dual shortwaves dig out of Saskatchewan/Alberta and into the
Northern Plains. As the northern shortwaves dive south and the Baja
low ejects east, the interaction of these features will lead to
increasing mid-level divergence overlapping pronounced height falls
to produce rich deep layer lift. This will be on top of an arctic
cold front that will be sagging southward into the Southern Plains
and eventually work its way southeast to the Gulf and Atlantic
coasts by Saturday. This overlapping ascent will materialize atop a
moistening column as subtropical moisture downstream of the Baja
low streams northeast reflected by IVT that reaches above the 97th
percentile according to NAEFS, in a broad swath from Texas to the
Carolinas, with above the record (CFSR at 00Z) climatology by
Sunday evening in the east.=20

This increasing moisture will result in a large swath of
precipitation expanding from the Southern Plains Friday, to the
Mississippi Valley and Tennessee Valley Saturday, into the
Carolinas and Mid-Atlantic by Sunday, and finally reaching the
Northeast Sunday night. This is a very large and impactful system
across a huge portion of this country. While impacts will be
considerable in many areas (aided by extreme cold), the icing (and
sleet) and snow will be most impressive across two distinct areas.

Freezing Rain and Sleet:
Arguably the most lasting impact associated with this winter storm
could be from heavy accumulating freezing rain and sleet stretching
from the southern Plains, Mid- South, Tennessee Valley, and
southern Mid-Atlantic. This is due to very cold low-level arctic
air being reinforced by the strong high over the north-central U.S.
(and enhanced by pronounced mid-level confluence over the Great
Lakes and New England) and a warm nose aloft (at around 750mb per
cross section model soundings) melting snow as it falls through the
column before refreezing just before or at the surface,and in some
places this re-freezing layer is above the 90th percentile in terms
of depth, suggesting some locations will experience exceptional
sleet accumulations.=20

The greatest freezing rain amounts and impacts are currently=20
forecast across northeast TX through northern MS as favorable=20
thermal profiles linger for over 24 hours beginning Friday night.=20
WPC 72-hour probabilities for >0.5" of freezing rain are high >70%=20
across southern AR into parts of northwest MS. Here, ice accretion=20
could be crippling and exceed 0.75-1.00", (WPC probabilities above
50% for 1" if ice) which would almost certainly lead to widespread
long-lasting damage to infrastructure, including power outages and
tree damage. Major sleet accumulations are also likely just north=20
of the freezing rain area stretching from southern OK/north TX=20
through central AR and into the Mid- South, with more than a few=20
inches of sleet possible. The consistency of the guidance in both=20
placement and amounts for this area are resulting in high=20
confidence in an extreme event, leading to long-lasting impacts=20
both to travel and infrastructure due to the bitterly cold airmass=20
expected to linger into next week over the region.

Heavy icing is also expected farther east into the southern=20
Appalachians and southern Mid-Atlantic. The setup across the=20
southern Mid- Atlantic down as far south as northern GA and areas=20
just inland from the coasts of the Carolinas is an extreme case of=20
CAD with a 1040mb high situated over the Interior Northeast on=20
Saturday night. While regional soundings indicate there may be
considerable sleet in this area as well, especially across southern
VA into northern NC, these CADs are notorious for their effective dry/isallobaric flow, enhanced by precipitation, leading to dry
wet-bulb advection offsetting the latent heat of freezing during
freezing rain. With such an impressive high in place at
precipitation onset, this will likely result in considerable
accumulations of sleet and freezing rain here, too, with WPC
probabilities indicating a moderate risk (50-70%) of at least 0.5",
highest across the Piedmont. The guidance has trended just a bit
colder this afternoon, but significant icing is also possible as
far north as Richmond, VA and towards the Chesapeake Bay.


Heavy Snow:
North of the mixed precipitation area and closely tied to both a
favorable LFQ of a zonally oriented 180kt upper jet and strong
700mb fgen, snow is the primary precipitation type stretching from
the southern High Plains of east-central NM and the southern
Rockies through the Plains, Mid-Mississippi Valley, Ohio Valley,
Mid-Atlantic, and reaching the Northeast by Sunday evening (with
additional expansion beyond this forecast period).=20

Favorable upslope flow as the strong arctic high pressure noses=20
southward along the High Plains behind a strong cold front starts=20
on Friday across the southern Rockies, with light snow and even a=20
chance for freezing drizzle at onset across the central Plains=20
until the column fully saturates. Heavy snow is then forecast to=20
begin breaking out Friday night from the central/southern Plains=20
through the mid-Mississippi Valley and spanning much of the Ohio=20
Valley and parts of the Midwest on Saturday. Snowfall rates could=20
near 1"/hr as strong lift through WAA/fgen intersects with a=20
region where the DGZ is forecast to be extremely deep (SREF
probabilities above 70% for >100mb of depth). This would allow for
efficient formation of dendrites where ample lift can fully=20
moisture the column. While this depth is impressive, regional
forecast soundings indicate that the best ascent may lie below this
DGZ in many areas, and there is only modest indication of any
isothermal layer beneath the DGZ to maintain aggregates. Despite
this, efficient and fluffy SLRs are likely in this area, and with a
long duration event expected, WPC probabilities are moderate
(30-50% )for at least 12 inches from eastern KS and OK into=20
southern MO, with widespread 4+ inches extending all the way back
into the TX Panhandle and lower MS VLY.

Farther east, some heavier snowfall is becoming more likely for
parts of the Ohio Valley, and into the Mid-Atlantic, and especially
Northeast. Here, pronounced WAA and accompanying 850-700mb fgen
will drive pronounced ascent into a rapidly moistening column
thanks to IVT above the 90th climatological percentile. As the
upper trough (interaction of the southern and northern streams)
deepens over the Plains, downstream ascent will maximize and a
period of impressive WAA snow with snowfall rates >1"/hr are
likely. As secondary low pressure develops offshore (in a Miller B
type evolution), banded structures within the WAA are likely to
translate northward from the Mid-Atlantic into New England, and
then may pivot and drift eastward Sunday night into Monday. Where
this occurs, the heaviest total snowfall accumulations are
probable, reflected by WPC probabilities that are already above 50%
for 12+ inches, and this is even with more of the event beyond this
forecast period (into New England). While there is some uncertainty
into how much mixing will pivot northward, especially closer to the
coast from Richmond, VA through Long Island, the interior portions
(NW of I-95 and into southern New England which will remain cold as
the secondary low develops and tracks near the 40/70 Benchmark)
will remain all snow with above-climo SLRs leading to significant
snowfall accumulations. Many areas are expected to receive more
than 12 inches from the Ohio Valley through the Mid-Atlantic and
into the Northeast before this system winds down on Monday /D4/.

Key Messages for this system are linked below (Key Message 2)


...Great Lakes...=20
Days 1-2...

Expansive mid-level low centered over the Hudson Bay will track
slowly southward this evening and then begin to shear open and
translate to the east as a secondary shortwave rotates through its
base and atop the Great Lakes Friday evening. Behind this impulse,
shortwave ridging will amplify across the area, bringing an end to
the persistent CAA and associated lake-induced ascent.

The subsequent W/NW flow and accompanying CAA will lead to
impressive lake effect snow (LES) in the favored W/NW snow belts
D1, with some pivoting to more N/NW D2 before waning. The heaviest
snowfall is likely east of Lake Ontario D1 where WPC
probabilities indicate a high risk (>70%) for at least 12 inches,=20
and 1-2 feet is possible across the Tug Hill Plateau. Elsewhere,=20
WPC probabilities suggest a moderate risk (50-70%) for at least 4=20
inches along the Chautauqua Ridge, western MI (east shore of Lake=20
Michigan) and across the northern U.P. During D2 the precipitation=20
intensity will weaken, but WPC probabilities suggest a moderate=20
risk (30-70%) for at least 2 inches in far NW IN and southeast of=20
Lake Ontario, before the shortwave ridging brings an end to this=20
round of LES.

Additionally, and this pivots into the Northeast as well, a second
round of snow squalls is possible on Friday along and behind an
arctic cold front traversing the region. For more details on the=20
snow squall threat in the Northeast through Friday, please refer to
our Key Messages (Key Messages 3) below.


Snell/Weiss





...Winter Storm Key Messages are in effect. Please see current=20
Key Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!-ZbcCxUHFaZzUCjVjcXjC8-1-t_ZYP0Ds_0gTb0a3UKg7= LWejAi__n66qDCj_90esw97-mNA9zZNPcoKLnZx6xUubt8$=20

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_2.png__;!!DZ3fjg!-ZbcCxUHFaZzUCjVjcXjC8-1-t_ZYP0Ds_0gTb0a3UKg7= LWejAi__n66qDCj_90esw97-mNA9zZNPcoKLnZx7Mmwhog$=20

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_3.png__;!!DZ3fjg!-ZbcCxUHFaZzUCjVjcXjC8-1-t_ZYP0Ds_0gTb0a3UKg7= LWejAi__n66qDCj_90esw97-mNA9zZNPcoKLnZx13dN6Ms$=20



$$

=3D =3D =3D
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FOUS11 KWBC 230858
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
358 AM EST Fri Jan 23 2026

Valid 12Z Fri Jan 23 2026 - 12Z Mon Jan 26 2026


...Major winter storm to bring the potential for crippling icing,=20 significant sleet, and heavy snow from the Southern Plains through=20
the Southeast and up the Atlantic Coast into New England...

Forecast remains largely on track with only minor changes compared
to the previous cycle, with typical uncertainties surrounding the=20
depth and northern push of the mid-level warm nose. While this=20
uncertainty is rather minor from a synoptic scale, local forecasts=20
can still be drastically impacted by this feature. The event will=20
begin this morning across the Southern Plains and expand towards
the MS VLY tonight. The driver of this winter storm is an=20
impressive overlap of intensifying synoptic ascent with increasing=20 subtropical moisture.

The synoptic pattern becomes favorable today in response to the=20
evolution of multiple shortwaves rotating through an amplifying=20
trough across the eastern CONUS. A closed 500mb low off the Baja=20
Peninsula will begin to open and shear to the east, at the same=20
time dual shortwaves dig out of Saskatchewan/Alberta and into the=20
Northern Plains. As the northern shortwaves dive south and the Baja
low ejects east, the interaction of these features will lead to=20
increasing mid-level divergence overlapping pronounced height falls
to produce rich deep layer lift. The northern shortwave has=20
trended a tad slower with overnight guidance and allows for more
ridging out ahead of this system, helping shift the mid-level warm
nose farther north. Regardless, the impressive ascent will be on=20
top of an arctic cold front that will be sagging southward into the
Southern Plains and eventually work its way southeast to the Gulf=20
and Atlantic coasts by Saturday. This overlapping ascent will=20
materialize atop a moistening column as subtropical moisture=20
downstream of the Baja low streams northeast reflected by IVT that=20
reaches above the 97th percentile according to NAEFS, in a broad=20
swath from Texas to the Carolinas, with above the record (CFSR at=20
00Z) climatology by Sunday evening in the east.

This increasing moisture will result in a large swath of
precipitation expanding from the Southern Plains today, to the=20
MS VLY and TN VLY Saturday, into the Carolinas and Mid- Atlantic=20
by Sunday, and finally reaching the Northeast Sunday night. This is
a very large and impactful system across a huge portion of this=20
country. While impacts will be considerable in many areas (aided by
extreme cold), the icing (and sleet) and snow will be most=20
impressive across two distinct areas.

Freezing Rain and Sleet:
Arguably the most lasting impact associated with this winter storm
could be from heavy accumulating freezing rain and sleet stretching
from the Southern Plains, Mid- South, Tennessee Valley, and=20
southern Mid-Atlantic. This is due to very cold low-level arctic=20
air being reinforced by the strong high over the north-central U.S.
(and enhanced by pronounced mid-level confluence over the Great=20
Lakes and New England) and a warm nose aloft (at around 750mb per=20
cross section model soundings) melting snow as it falls through the
column before refreezing just before or at the surface,and in some
places this re-freezing layer is above the 90th percentile in=20
terms of depth, suggesting some locations will experience=20
exceptional sleet accumulations.=20

The greatest freezing rain amounts and impacts are currently=20
forecast across northeast TX through northern MS as favorable=20
thermal profiles linger for over 24 hours beginning Friday night.=20
WPC 72-hour probabilities for >0.5" of freezing rain are high >70%=20
across southern AR/northern LA into parts of northern MS. Here,=20
ice accretion could be crippling and exceed 0.75-1.00", (WPC=20
probabilities 40-50% for 1" of ice) which would almost certainly=20
lead to widespread long-lasting damage to infrastructure, including
power outages and tree damage. Major sleet accumulations are also=20
likely just north of the freezing rain area stretching from=20
southern OK/north TX through central AR and into the Mid- South,=20
with more than a few inches of sleet possible. The consistency of=20
the guidance in both placement and amounts for this area are=20
resulting in high confidence in an extreme event, leading to long-=20
lasting impacts both to travel and infrastructure due to the=20
bitterly cold airmass expected to linger into next week over the=20
region.

Heavy icing is also expected farther east into the southern=20
Appalachians and southern Mid-Atlantic. The setup across the=20
southern Mid- Atlantic down as far south as northern GA and areas=20
just inland from the coasts of the Carolinas is an extreme case of=20
CAD with a 1040mb high situated over the Interior Northeast on=20
Saturday night. While regional soundings indicate there may be
considerable sleet in this area as well, especially across southern
VA into northern NC, these CADs are notorious for their effective dry/isallobaric flow, enhanced by precipitation, leading to dry
wet-bulb advection offsetting the latent heat of freezing during
freezing rain. With such an impressive high in place at
precipitation onset, this will likely result in considerable
accumulations of sleet and freezing rain here, too, with WPC
probabilities indicating a moderate-to-high risk (60-80%) of at=20
least 0.5", highest across the Piedmont and northern GA. The=20
guidance has trended just a bit colder this afternoon, but=20
significant icing is also possible as far north as Richmond, VA and
towards southern MD.

Heavy Snow:
North of the mixed precipitation area and closely tied to both a
favorable LFQ of a zonally oriented 180kt upper jet and strong
700mb fgen, snow is the primary precipitation type stretching from
the southern High Plains of east-central NM and the southern
Rockies through the Plains, Mid-Mississippi Valley, Ohio Valley,
Mid-Atlantic, and reaching the Northeast by Sunday evening (with
additional expansion beyond this forecast period).=20

Favorable upslope flow as the strong arctic high pressure noses=20
southward along the High Plains behind a strong cold front starts=20
on Friday across the southern Rockies, with light snow and even a=20
chance for freezing drizzle at onset across the central Plains=20
until the column fully saturates. Heavy snow is then forecast to=20
begin breaking out Friday night from the central/southern Plains=20
through the mid-Mississippi Valley and spanning much of the Ohio=20
Valley and parts of the Midwest on Saturday. Snowfall rates could=20
near 1"/hr as strong lift through WAA/fgen intersects with a=20
region where the DGZ is forecast to be extremely deep (SREF
probabilities above 70% for >100mb of depth). This would allow for
efficient formation of dendrites where ample lift can fully=20
moisture the column. While this depth is impressive, regional
forecast soundings indicate that the best ascent may lie below this
DGZ in many areas, and there is only modest indication of any
isothermal layer beneath the DGZ to maintain aggregates. Despite
this, efficient and fluffy SLRs are likely in this area, and with a
long duration event expected, WPC probabilities are moderate
(40-60% )for at least 12 inches from southeastern KS and
northeastern OK into southern MO, with widespread 4+ inches=20
extending all the way back into the TX Panhandle and lower MS VLY.
Trends have been more favorable for snow vs lately on D1 across
eastern OK and central AR as guidance depicts stronger mid-level
fgen and dynamic cooling aloft to keep the entire column below 0C.
00z HREF also depicts the potential for 1"/hr snowfall rates in
this region. Will monitor this for potential adjustments=20
downstream.

Farther east, some heavier snowfall is becoming more likely for
parts of the Ohio Valley, and into the Mid-Atlantic, and especially
Northeast. Here, pronounced WAA and accompanying 850-700mb fgen
will drive pronounced ascent into a rapidly moistening column
thanks to IVT above the 90th climatological percentile. As the
upper trough (interaction of the southern and northern streams)
deepens over the Plains, downstream ascent will maximize and a
period of impressive WAA snow with snowfall rates >1"/hr are
likely. As secondary low pressure develops offshore (in a Miller B
type evolution), banded structures within the WAA are likely to
translate northward from the Mid-Atlantic into New England, and
then may pivot and drift eastward Sunday night into Monday. Where
this occurs, the heaviest total snowfall accumulations are
probable, reflected by WPC probabilities that are already above 60%
for 12+ inches. While there is some uncertainty into how much=20
mixing will pivot northward, especially from Washington D.C.=20
through Long Island, the interior portions (NW of I-95 and into=20
southern New England which will remain cold as the secondary low=20
develops and tracks near the 40/70 Benchmark) will remain mostly=20
snow with above- climo SLRs leading to significant snowfall=20
accumulations. One other uncertainty that has creeped into the
forecast is a pesky dry slot moving into the Mid-Atlantic and
Northeast Sunday night. This could dry out the mid-level and
drastically cut both precipitation and SLRs. In fact, freezing
drizzle could develop early Monday morning from northern Va to
northern NJ in this scenario before stronger westerly flow picks=20
up on Monday. Many areas are expected to receive more than 12=20
inches from the Ohio Valley through the Mid- Atlantic and into the=20
Northeast before this system winds down in New England on Monday=20
/D4/.

Key Messages for this system are linked below (Key Message 2)


...Great Lakes...=20
Day 1...

Expansive mid-level low centered over the Hudson Bay will begin to
shear open and translate to the east today as a secondary=20
shortwave rotates through its base and atop the Great Lakes this
evening. Behind this impulse, shortwave ridging will amplify=20
across the area, bringing an end to the persistent CAA and=20
associated lake- induced ascent on D1.

The subsequent W/NW flow and accompanying CAA will lead to
impressive lake effect snow (LES) in the favored W/NW snow belts
D1, with some pivoting to more N/NW by early Saturday. The=20
heaviest snowfall is likely east of Lake Ontario D1 where WPC=20
probabilities indicate a moderate risk (50-70%) for at least 8
additional inches in the Tug Hill Plateau. Elsewhere, WPC=20
probabilities suggest a moderate risk (50-70%) for at least 6=20
additional inches across the northeastern U.P.

Additionally, as an arctic cold front pivots into the Northeast,=20
snow squalls along and behind this front are possible. For more=20
details on the snow squall threat in the Northeast through Friday,=20
please refer to our Key Messages (Key Messages 3) below.


Snell/Weiss






...Winter Storm Key Messages are in effect. Please see current=20
Key Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!6i-JszDvIoz4IkeeFVBNKHjZJfHF0Ybqz-c67ZQcVC-f7= lPz-fsyMDtCovzI6Va6oo9mesLuh66CAbzexuk2Xq7kUJc$=20

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_2.png__;!!DZ3fjg!6i-JszDvIoz4IkeeFVBNKHjZJfHF0Ybqz-c67ZQcVC-f7= lPz-fsyMDtCovzI6Va6oo9mesLuh66CAbzexuk2eCfbSq8$=20

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_3.png__;!!DZ3fjg!6i-JszDvIoz4IkeeFVBNKHjZJfHF0Ybqz-c67ZQcVC-f7= lPz-fsyMDtCovzI6Va6oo9mesLuh66CAbzexuk2Uae-1TY$=20



$$

=3D =3D =3D
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FOUS11 KWBC 232057
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
357 PM EST Fri Jan 23 2026

Valid 00Z Sat Jan 24 2026 - 00Z Tue Jan 27 2026


...Major winter storm to bring the potential for crippling icing,=20 significant sleet, and heavy snow from the Southern Plains through=20
the Southeast and up the Atlantic Coast into New England...

Meteorological Overview...

A massive winter storm, set to produce a swath of heavy snow and=20
dangerous ice accumulations, has begun today as tropical East=20
Pacific moisture streams out ahead of the 500mb closed low near the
Baja Peninsula. This moisture plume is clashing with the coldest=20
air-mass of the season, entrenching itself over the Nation's=20
Heartland. The moisture transport is exceptional with an
integrated vapor transport (IVT) above the 97.5 climatological=20
percentile per ECMWF SATs. The rich moisture from the south will=20
accompany strong 850-700mb WAA that results in classic over-runing=20
along a developing area of 850-700mb FGEN atop the Southern Plains.
Meanwhile, the upper trough in the Southwest and an emerging=20
upper- level shortwave trough over the Dakotas will strengthen a=20
250mb jet streak over the east-central U.S., placing its thermally-
direct right-entrance region over the Southern Plains. This=20
synoptic- scale setup helps to enhance the mesoscale below,=20
fostering heavy bands of snow and even elevated instability above=20
the low-level sub-freezing layer over north TX on east into the=20
Mid-South tonight and into Saturday.

By Saturday, as the upper low near Baja approaches Texas, its=20
associated jet streak over Mexico will co-locate its divergent=20
left-exit region over the Mid-South and maximize upper-level ascent
over the region. The IVT in advance of the upper trough over=20
Mexico is both expansive and strong with >90th climatological=20
percentile IVT values originating south of Mexico and extending all
the way to the Southern Appalachians by Saturday afternoon. The=20
remarkable extent of the IVT and the slow progression of the Mexico
trough is why parts of the South and Mid-Atlantic are likely to=20
see snow, sleet, and freezing rain for over 24 hours and in some=20
cases approaching 48 hours. As arctic high pressure slides east, a=20
cold-air damming (CAD) signature will become well pronounced along=20
and east of the Appalachians as anomalous Pacific and Gulf moisture
arrives, leading to precipitation falling into the frigid air-mass
and supporting heavy snow, sleet, and freezing rain totals from=20
the southern Appalachians to the Mid-Atlantic.=20

Saturday night and into Sunday is where most changes in the
forecast have unfolded of late. It remains unclear just how strong
the emerging area of low pressure near the Gulf Coast will be and=20
how far north it gets. It is noteworthy that guidance is in good=20
agreement on 700mb Q-vector convergence over northern AL and the=20
southern Appalachians, but the GFS is a little farther south in=20
positioning while the ECMWF is a littler farther north and=20
stronger, resulting in the northern shifts over the last couple=20
days. What they do both agree on is by Sunday, a very pronounced=20
area of strong 700mb Q-vector convergence will unfold along the=20
Mid-Atlantic coast, prompting the development of a coastal low=20
along a strengthening coastal front. With the benefit of the 250mb
jet streak's divergent right-entrance region aloft and the=20
strengthening IVT (ECMWF SATs show >99.5 climatological percentile=20
values over the Southeast Sunday morning), an expansive=20
precipitation shield will span across the OH Valley, Mid-Atlantic,=20
and Northeast with excessive amounts of wintry precipitation=20
falling. While there remains some question on precipitation type,=20
the ECMWF EFI shows the QPF is >0.8 from the Southern Plains and=20
Mid-South to the Northeast, implying an unusually high amount of=20
QPF for this time of year will be at this winter storm's disposal=20
as it falls into a bitterly cold Arctic air-mass.=20

Heavy Snow/Sleet...

The latest forecast calls an astonishingly long swath (over 2,000=20
mile long in length) of >6" of snowfall that starts in the Sangre=20
De Cristo and Sacramento mountains of New Mexico all the way to=20
Downeast Maine. It is worth noting that the snowfall probabilities=20
being referenced will have snow and sleet. Focusing on the Plains=20
first, WPC probabilities sport high chances (>70%) for snowfall >8"
over central OK, southeast KS, southwest MO, and northwest AR.=20
There is another impressive swath of high chance probabilities=20

70%) for >8" of snow from southern IN and north-central KY to=20

eastern Maine. The Central Appalachians, interior Northeast, and=20
southern New England are likely to see the most snowfall with high=20
chances (>70%) for over a foot of snow in these areas. In fact, WPC probabilities show low-to-moderate chances (30-50%) for totals=20
over 18" in the Catskills, Berkshires, and eastern MA. Farther=20
south, the inclusion of sleet from NY and Long Island southward=20
along the I-95 corridor will likely cut into snowfall totals.=20 Climatologically speaking, areas west of I-95 where topography=20
increases are most likely to see more snow than sleet. This is=20
evident in the >8" for snow and sleet probabilities where they are=20
high (>70% chances) from northwest VA and north-central MD along=20
Parrs Ridge to the Lower Susquehanna Valley, but below 50% over=20
southern NJ, the MD eastern shore, and south of Fredericksburg, VA.
Still, the WSO shows >50% chances for a warning-level snowfall as=20
far south as central VA on east through the northern DelMarVa and=20
into southern NJ due to the strong 850-700mb FGEN Saturday night=20
and Sunday morning that fosters snowfall rates that could ranges
between 1-2"/hr. So while snowfall/sleet totals are not quite as=20
high as their neighbors to the north, the combination of snow,=20
sleet, and inclusion of some freezing rain still support=20
significant travel disruptions in these southern areas as well.=20

The WSSI shows widespread Major Impacts (considerable disruptions
to daily life: dangerous to impossible driving conditions,=20
widespread closures, and disruptions to infrastructure) from the TX
Panhandle on east to the Ozarks, through the OH Valley, and all the
way to New England. Every major market along the I-95 metropolitan
corridor (Washington D.C. to Boston and even as far north as
Portland, ME) are expecting major impacts due to snow. The=20
D.C/Baltimore area on north to Philly and NYC are likely to see=20
some inclusion of sleet, but it will still result in significant=20
impacts when accounting for heavy snowfall that is expected to
exceed warning criteria (5-6"). A reminder that bitterly cold=20
temperatures will follow in wake of this storm Monday and into the=20
middle of the week throughout the eastern U.S.. The snow/sleet=20
impacts will linger well into next week with rounds of re-freezing=20
that keeps surfaces icy and dangerous to both drive and walk on for
the foreseeable future. Those in the path of this storm should=20
make final preparations and put plans in place for significant=20
travel disruptions this weekend and into at least early next week.


Freezing Rain:

The most lasting and dangerous impact will come as a result of=20
significant to locally catastrophic ice accumulations due to=20
prolonged periods of freezing rain. Just like the swath of >6" of=20
snowfall, the areal coverage of high chances (>50%) in WPC's ice=20 probabilities exceeding one-quarter inch of ice accumulation is=20
both impressive and alarming. From east-central TX to southern AR,=20
northern LA, northern MS, the TN Valley, northern GA, the southern=20 Appalachians, and southern Mid-Atlantic, these regions are all=20
likely to experience anywhere from one-quarter to one-half inch of=20
ice. Widespread power outages and tree damage is likely in these=20
areas, especially from the Lower MS Valley, southern Appalachians,=20
and central NC where there are also high chances (>70%) for ice=20 accumulations over one-half inch. It is parts of northern AL,=20
northern MS, south-central TN, far northern GA, the southern=20
Appalachians, and the NC Piedmont that are of greatest concern.=20
WPC probabilities show low-to-moderate chances (20-40%) for ice=20 accumulations over 1 inch. These areas are likely to endure a=20
crippling ice storm that will take days, if not weeks, of clean up=20
in addition to extended power outages. Residents in these areas=20
should take final preparations now. Once the freezing rain starts,=20
dangerous travel will be common not only during the event, but in=20
the days in wake of the storm due to prolonged sub-freezing=20
temperatures that cause persistent re-freezing on all untreated=20
surfaces. The Key Messages for the Extreme Cold are linked below
(Key Message 1).

Farther east, freezing rain will reach southern VA, the DelMarVa
Peninsula, and as far north as southern NJ. The southern VA
Piedmont, including the Richmond metro area, have moderate chances
(40-60%) for over one-half inch of ice. The WSSI depicts Major=20
Impacts from Richmond on south along I-95 into NC, while Moderate=20
Impacts (hazardous travel conditions) are anticipated as far north=20
as the northern DelMarVa Peninsula and into the Lower Delaware=20
Valley. While most areas farther north towards the Lower Delaware=20
Valley and southern NJ should largely remain sleet, it may=20
transition to freezing rain for a brief time by Sunday evening. WPC probabilities show low-to-moderate chances (30-50%) for over one-=20
tench of an inch of ice accumulations Sunday evening.


Key Messages for this system are linked below (Key Message 2)


Mullinax



...Winter Storm Key Messages are in effect. Please see current=20
Key Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!8GUWGIKvjpbH7j06LCzf76dgj7wKmpMcynczXffJXXaY-= mNp6L2dr8o-PiAMPcRJ2YyFHPbCmPdKNKW5sTA1hXXuSxM$=20

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_2.png__;!!DZ3fjg!8GUWGIKvjpbH7j06LCzf76dgj7wKmpMcynczXffJXXaY-= mNp6L2dr8o-PiAMPcRJ2YyFHPbCmPdKNKW5sTA1nTFVkNQ$=20

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_3.png__;!!DZ3fjg!8GUWGIKvjpbH7j06LCzf76dgj7wKmpMcynczXffJXXaY-= mNp6L2dr8o-PiAMPcRJ2YyFHPbCmPdKNKW5sTA1sbzsBKw$=20



$$

=3D =3D =3D
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--- SBBSecho 3.28-Linux
* Origin: Capitol City Online (1:2320/105)

FOUS11 KWBC 232103
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
403 PM EST Fri Jan 23 2026

Valid 00Z Sat Jan 24 2026 - 00Z Tue Jan 27 2026


...Major winter storm to bring the potential for crippling icing,=20 significant sleet, and heavy snow from the Southern Plains through=20
the Southeast and up the Atlantic Coast into New England...

Meteorological Overview...

A massive winter storm, set to produce a swath of heavy snow and=20
dangerous ice accumulations, has begun today as tropical East=20
Pacific moisture streams out ahead of the 500mb closed low near the
Baja Peninsula. This moisture plume is clashing with the coldest=20
air-mass of the season, entrenching itself over the Nation's=20
Heartland. The moisture transport is exceptional with an
integrated vapor transport (IVT) above the 97.5 climatological=20
percentile per ECMWF SATs. The rich moisture from the south will=20
accompany strong 850-700mb WAA that results in classic over-runing=20
along a developing area of 850-700mb FGEN atop the Southern Plains.
Meanwhile, the upper trough in the Southwest and an emerging=20
upper- level shortwave trough over the Dakotas will strengthen a=20
250mb jet streak over the east-central U.S., placing its thermally-
direct right-entrance region over the Southern Plains. This=20
synoptic- scale setup helps to enhance the mesoscale below,=20
fostering heavy bands of snow and even elevated instability above=20
the low-level sub-freezing layer over north TX on east into the=20
Mid-South tonight and into Saturday.

By Saturday, as the upper low near Baja approaches Texas, its=20
associated jet streak over Mexico will co-locate its divergent=20
left-exit region over the Mid-South and maximize upper-level ascent
over the region. The IVT in advance of the upper trough over=20
Mexico is both expansive and strong with >90th climatological=20
percentile IVT values originating south of Mexico and extending all
the way to the Southern Appalachians by Saturday afternoon. The=20
remarkable extent of the IVT and the slow progression of the Mexico
trough is why parts of the South and Mid-Atlantic are likely to=20
see snow, sleet, and freezing rain for over 24 hours and in some=20
cases approaching 48 hours. As arctic high pressure slides east, a=20
cold-air damming (CAD) signature will become well pronounced along=20
and east of the Appalachians as anomalous Pacific and Gulf moisture
arrives, leading to precipitation falling into the frigid air-mass
and supporting heavy snow, sleet, and freezing rain totals from=20
the southern Appalachians to the Mid-Atlantic.=20

Saturday night and into Sunday is where most changes in the
forecast have unfolded of late. It remains unclear just how strong
the emerging area of low pressure near the Gulf Coast will be and=20
how far north it gets. It is noteworthy that guidance is in good=20
agreement on 700mb Q-vector convergence over northern AL and the=20
southern Appalachians, but the GFS is a little farther south in=20
positioning while the ECMWF is a littler farther north and=20
stronger, resulting in the northern shifts over the last couple=20
days. What they do both agree on is by Sunday, a very pronounced=20
area of strong 700mb Q-vector convergence will unfold along the=20
Mid-Atlantic coast, prompting the development of a coastal low=20
along a strengthening coastal front. With the benefit of the 250mb
jet streak's divergent right-entrance region aloft and the=20
strengthening IVT (ECMWF SATs show >99.5 climatological percentile=20
values over the Southeast Sunday morning), an expansive=20
precipitation shield will span across the OH Valley, Mid-Atlantic,=20
and Northeast with excessive amounts of wintry precipitation=20
falling. While there remains some question on precipitation type,=20
the ECMWF EFI shows the QPF is >0.8 from the Southern Plains and=20
Mid-South to the Northeast, implying an unusually high amount of=20
QPF for this time of year will be at this winter storm's disposal=20
as it falls into a bitterly cold Arctic air-mass.=20

Heavy Snow/Sleet...

The latest forecast calls an astonishingly long swath (over 2,000=20
mile long in length) of >6" of snowfall that starts in the Sangre=20
De Cristo and Sacramento mountains of New Mexico all the way to=20
Downeast Maine. It is worth noting that the snowfall probabilities=20
being referenced will have snow and sleet. Focusing on the Plains=20
first, WPC probabilities sport high chances (>70%) for snowfall >8"
over central OK, southeast KS, southwest MO, and northwest AR.=20
There is another impressive swath of high chance probabilities=20

70%) for >8" of snow from southern IN and north-central KY to=20

eastern Maine. The Central Appalachians, interior Northeast, and=20
southern New England are likely to see the most snowfall with high=20
chances (>70%) for over a foot of snow in these areas. In fact, WPC probabilities show low-to-moderate chances (30-50%) for totals=20
over 18" in the Catskills, Berkshires, and eastern MA. Farther=20
south, the inclusion of sleet from NY and Long Island southward=20
along the I-95 corridor will likely cut into snowfall totals.=20 Climatologically speaking, areas west of I-95 where topography=20
increases are most likely to see more snow than sleet. This is=20
evident in the >8" for snow and sleet probabilities where they are=20
high (>70% chances) from northwest VA and north-central MD along=20
Parrs Ridge to the Lower Susquehanna Valley, but below 50% over=20
southern NJ, the MD eastern shore, and south of Fredericksburg, VA.
Still, the WSO shows >50% chances for a warning-level snowfall as=20
far south as central VA on east through the northern DelMarVa and=20
into southern NJ due to the strong 850-700mb FGEN Saturday night=20
and Sunday morning that fosters snowfall rates that could ranges
between 1-2"/hr. So while snowfall/sleet totals are not quite as=20
high as their neighbors to the north, the combination of snow,=20
sleet, and inclusion of some freezing rain still support=20
significant travel disruptions in these southern areas as well.=20

The WSSI shows widespread Major Impacts (considerable disruptions
to daily life: dangerous to impossible driving conditions,=20
widespread closures, and disruptions to infrastructure) from the TX
Panhandle on east to the Ozarks, through the OH Valley, and all the
way to New England. Every major market along the I-95 metropolitan
corridor (Washington D.C. to Boston and even as far north as
Portland, ME) are expecting major impacts due to snow. The=20
D.C/Baltimore area on north to Philly and NYC are likely to see=20
some inclusion of sleet, but it will still result in significant=20
impacts when accounting for heavy snowfall that is expected to
exceed warning criteria (5-6"). A reminder that bitterly cold=20
temperatures will follow in wake of this storm Monday and into the=20
middle of the week throughout the eastern U.S.. The snow/sleet=20
impacts will linger well into next week with rounds of re-freezing=20
that keeps surfaces icy and dangerous to both drive and walk on for
the foreseeable future. Those in the path of this storm should=20
make final preparations and put plans in place for significant=20
travel disruptions this weekend and into at least early next week.


Freezing Rain...

The most lasting and dangerous impact will come as a result of=20
significant to locally catastrophic ice accumulations due to=20
prolonged periods of freezing rain. Just like the swath of >6" of=20
snowfall, the areal coverage of high chances (>50%) in WPC's ice=20 probabilities exceeding one-quarter inch of ice accumulation is=20
both impressive and alarming. From east-central TX to southern AR,=20
northern LA, northern MS, the TN Valley, northern GA, the southern=20 Appalachians, and southern Mid-Atlantic, these regions are all=20
likely to experience anywhere from one-quarter to one-half inch of=20
ice. Widespread power outages and tree damage is likely in these=20
areas, especially from the Lower MS Valley, southern Appalachians,=20
and central NC where there are also high chances (>70%) for ice=20 accumulations over one-half inch.=20

It is parts of northern AL, northern MS, south-central TN, far=20
northern GA, the southern Appalachians, and the NC Piedmont that=20
are of greatest concern. WPC probabilities show low-to-moderate=20
chances (20-40%) for ice accumulations over 1 inch. These areas are
likely to endure a crippling ice storm that will take days, if not
weeks, of clean up in addition to extended power outages. This is=20 demonstrated in a rare Extreme Impact on the WSSI in parts of
northern MS, far southern TN, and the Southern Appalachians. The
WSSI Extreme criteria references the potential for "extensive and=20
widespread closures, extremely dangerous travel, and life-saving=20
actions may be needed." Residents in these all referenced regions=20
above should take final preparations now. Once the freezing rain=20
starts, dangerous travel will be common not only during the event,=20
but in the days in wake of the storm due to prolonged sub-freezing=20 temperatures that cause persistent re-freezing on all untreated=20
surfaces. The Key Messages for the Extreme Cold are linked below=20
(Key Message 1).

Farther east, freezing rain will reach southern VA, the DelMarVa
Peninsula, and as far north as southern NJ. The southern VA
Piedmont, including the Richmond metro area, have moderate chances
(40-60%) for over one-half inch of ice. The WSSI depicts Major=20
Impacts from Richmond on south along I-95 into NC, while Moderate=20
Impacts (hazardous travel conditions) are anticipated as far north=20
as the northern DelMarVa Peninsula and into the Lower Delaware=20
Valley. While most areas farther north towards the Lower Delaware=20
Valley and southern NJ should largely remain sleet, it may=20
transition to freezing rain for a brief time by Sunday evening. WPC probabilities show low-to-moderate chances (30-50%) for over one-=20
tench of an inch of ice accumulations Sunday evening.


Key Messages for this system are linked below (Key Message 2)


Mullinax




...Winter Storm Key Messages are in effect. Please see current=20
Key Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!8yFFARuqbgrlMXfpwPGS4uJRxeJOXQOZNw6H1nZpRTRha= rrS6kEy-awMjMQhdY74aJIFWgelYkKRsYNo7so9y2A1flY$=20

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_2.png__;!!DZ3fjg!8yFFARuqbgrlMXfpwPGS4uJRxeJOXQOZNw6H1nZpRTRha= rrS6kEy-awMjMQhdY74aJIFWgelYkKRsYNo7so9tj5CnIA$=20

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_3.png__;!!DZ3fjg!8yFFARuqbgrlMXfpwPGS4uJRxeJOXQOZNw6H1nZpRTRha= rrS6kEy-awMjMQhdY74aJIFWgelYkKRsYNo7so9VdC50ig$=20



$$

=3D =3D =3D
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--- SBBSecho 3.28-Linux
* Origin: Capitol City Online (1:2320/105)

FOUS11 KWBC 240838
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
338 AM EST Sat Jan 24 2026

Valid 12Z Sat Jan 24 2026 - 12Z Tue Jan 27 2026


...Ongoing major winter storm to bring the potential for crippling
icing, significant sleet, and heavy snow from the Southern
Rockies/Plains through the Southeast and up the Atlantic Coast=20
into New England...

Meteorological Overview...

Forecast remains on track as a massive winter storm, set to=20
produce a swath of heavy snow and dangerous ice accumulations, has=20
begun across the southern Rockies and Plains as tropical East=20
Pacific moisture streams out ahead of the 500mb closed low near the
Baja Peninsula. This moisture plume is clashing with the coldest=20
air- mass of the season, entrenching itself over the Nation's=20
Heartland. The moisture transport is exceptional with an integrated
vapor transport (IVT) above the 97.5 climatological percentile per
ECMWF SATs. The rich moisture from the south will accompany strong
850-700mb WAA that results in classic over-runing along an area of
850-700mb FGEN stretching from atop the Southern Plains to the TN=20
VLY and southern Mid-Atlantic by tonight. Meanwhile, the upper=20
trough in the Southwest and an emerging upper- level shortwave=20
trough over the Dakotas will strengthen a zonally oriented 250mb=20
jet streak over the east- central U.S., placing its thermally-=20
direct right- entrance region over the Southern Plains and Mid-=20
South. This synoptic- scale setup helps to enhance the mesoscale=20
below, fostering heavy bands of snow and even elevated instability=20
above the low-level sub- freezing layer over north TX on east into=20
the Mid-South today.

As the upper low near Baja approaches Texas by tonight, its=20
associated jet streak over Mexico will co-locate its divergent=20
left-exit region over the southern Plains and Mid-South, maximizing=20
upper- level ascent over the region. The IVT in advance of the=20
upper trough over Mexico is both expansive and strong with >90th=20 climatological percentile IVT values originating south of Mexico=20
and extending all the way to the Southern Appalachians by Saturday=20 afternoon. The remarkable extent of the IVT and the slow=20
progression of the Mexico trough is why parts of the South and Mid-
Atlantic are likely to see snow, sleet, and freezing rain for over
24 hours and in some cases approaching 48 hours. As arctic high=20
pressure slides east, a substantial cold- air damming (CAD)=20
signature will become well pronounced along and east of the=20
Appalachians as anomalous Pacific and Gulf moisture arrives,=20
leading to precipitation falling into the frigid air-mass and=20
supporting heavy snow, sleet, and freezing rain totals from the=20
southern Appalachians to the Mid-Atlantic.=20

Saturday night (tonight) into Sunday is when this event truly=20
starts to peak in expansiveness and magnitude with wintry=20
precipitation continuously spanning from New Mexico to the=20
Northeast. Given the event is now well within the short range and=20
the synoptic pattern is locked into place, uncertainty now mostly=20
lies within the thermodynamics and both the depth as well as=20
latitudinal reach of the mid-level warm nose. Depending on which=20
CAM or global guidance you look at, this warm nose still has about=20
100 miles of uncertainty. This uncertainty is most notable where=20
WAA is strongest, throughout the Mid-Atlantic and into the=20
Northeast Saturday night into Sunday. Here, the NAM3k and RRFS=20
remain the farthest north and GFS/FV3 farthest south. WPC=20
preference tonight was in the middle, somewhere between the CMC-=20
Regional and NAM3k with how far north mixing would reach. What all=20
models do both agree on is by Sunday, a very pronounced area of=20
strong 700mb Q-vector convergence will unfold along the Mid-=20
Atlantic coast, prompting the development of a coastal low along a=20 strengthening coastal front. With the benefit of the 250mb jet=20
streak's divergent right- entrance region aloft and the=20
strengthening IVT (ECMWF SATs show >99.5 climatological percentile=20
values over the Southeast Sunday morning), an expansive=20
precipitation shield will span across the OH Valley, Mid-Atlantic,=20
and Northeast with excessive amounts of wintry precipitation=20
falling. While there remains some question on precipitation type,=20
NBM probabilities for >1.0" of QPF for the this event are greater=20
than 70% from the Southern Plains to southern New England, implying
a high amount of QPF that will be at this winter storm's disposal.


Heavy Snow/Sleet...

The latest forecast calls an astonishingly long swath (over 2,000=20
mile long in length) of >6" of snowfall that starts in the Sangre=20
De Cristo and Sacramento mountains of New Mexico all the way to=20
Downeast Maine. It is worth noting that the snowfall probabilities=20
being referenced will have snow and sleet and not include snowfall
already fallen prior to 12Z Saturday (this morning). Focusing on=20
the Plains first, WPC probabilities sport medium chances (50-70%%)
for snowfall >8" over the TX Panhandle, central OK, southern MO,
and northern AR. There is another impressive swath of high chance=20 probabilities (>70%) for >8" of snow from southern IL/IN and=20
north- central KY to eastern Maine. The Central Appalachians,=20
interior Northeast, and southern New England are likely to see the=20
most snowfall with high chances (>70%) for over a foot of snow in=20
these areas. In fact, WPC probabilities show low- to-moderate=20
chances (30-50%) for totals over 18" in the Catskills, Berkshires,=20
and eastern MA to the southern coast of ME. Farther south, the=20
inclusion of sleet from the LI sound southward along the I-95=20
corridor will likely cut into snowfall totals. Climatologically=20
speaking, areas west of I-95 where topography increases are most=20
likely to see more snow than sleet. This is evident in the >8" for=20
snow and sleet probabilities where they are high (>70% chances)=20
from northwest VA and north- central MD along Parr's Ridge to the=20
Lower Susquehanna Valley, but below 50% over southern NJ, the MD=20
eastern shore, and south of Fredericksburg, VA. Still, the WSO=20
shows >50% chances for a warning-level snowfall as far south as=20
central VA on east through the northern DelMarVa and into southern=20
NJ due to the strong 850-700mb FGEN Saturday night and Sunday=20
morning that fosters snowfall rates that could ranges between=20
1-2"/hr just north of the warm nose and changeover to sleet. This=20
FGEN is so strong in several CAMs as it lifts northward into the=20
Northeast on Sunday, mostly in part to the extreme thermal=20
gradient in place, that a few instances of thundersnow shouldn't=20
be ruled out. Even for areas that don't remain 100 percent snow,=20
the combination of snow, sleet, and inclusion of some freezing rain
still support significant travel disruptions in these southern=20
areas as well.=20

The WSSI shows widespread Major Impacts (considerable disruptions
to daily life: dangerous to impossible driving conditions,=20
widespread closures, and disruptions to infrastructure) from the TX
Panhandle on east to the Ozarks, through the OH Valley, and all the
way to New England. Every major market along the I-95 metropolitan
corridor (Washington D.C. to Boston and even as far north as
Portland, ME) are expecting major impacts due to snow. The=20
D.C/Baltimore area on north to Philly and NYC are likely to see=20
some inclusion of sleet, but it will still result in significant=20
impacts when accounting for heavy snowfall that is expected to
exceed warning criteria (5-6"). Coastal New England, including the
Boston metro region could also see winds increase to near-blizzard
conditions as wind gusts increase to 30-40 mph due to the
strengthening surface low and continued high snowfall rates. A=20
reminder that bitterly cold temperatures will follow in wake of=20
this storm Monday and into the middle of the week throughout the=20
eastern U.S.. The snow/sleet impacts will linger well into next=20
week with rounds of re-freezing that keeps surfaces icy and=20
dangerous to both drive and walk on for the foreseeable future.=20
Those in the path of this storm should follow advice of local
officials.


Freezing Rain...

The most lasting and dangerous impact will come as a result of=20
significant to locally catastrophic ice accumulations due to=20
prolonged periods of freezing rain. Just like the swath of >6" of=20
snowfall, the areal coverage of high chances (>50%) in WPC's ice=20 probabilities exceeding one-quarter inch of ice accumulation is=20
both impressive and alarming. From east-central TX to southern AR,=20
northern LA, northern MS, the TN Valley, northern GA, the southern=20 Appalachians, and southern Mid-Atlantic, these regions are all=20
likely to experience anywhere from one-quarter to one-half inch of=20
ice. Widespread power outages and tree damage is likely in these=20
areas, especially from the Lower MS Valley, southern Appalachians,
central NC, and south-central VA, where there are also medium=20
chances (>50%) for ice accumulations over one-half inch.=20

It is parts of northwest AL, northern MS, south-central TN,
southeast AR, northern LA, far northern GA, the southern=20
Appalachians, and the NC Piedmont that are of greatest concern. WPC probabilities show low- to- moderate chances (20-40%) for ice=20
accumulations over 1 inch and higher probabilities (30-60%) across
parts of northern/northwestern MS. These areas are likely to=20
endure a crippling ice storm that will take days, if not weeks, of=20
clean up in addition to extended power outages while bitterly cold
temperatures linger into next week. This is demonstrated in a rare
Extreme Impact on the WSSI in parts of northern MS, northeast LA, and
the Southern Appalachians. The WSSI Extreme criteria references=20
the potential for "extensive and widespread closures, extremely=20
dangerous travel, and life- saving actions may be needed." Once=20
the freezing rain starts, dangerous travel will be common not only=20
during the event, but in the days in wake of the storm due to=20
prolonged sub- freezing temperatures that cause persistent re-=20
freezing on all untreated surfaces. The Key Messages for the=20
Extreme Cold are linked below (Key Message 1).

Farther east, freezing rain will reach southern VA, the DelMarVa
Peninsula, and as far north as the I-95 corridor from Washington
D.C. to Philadelphia. The southern VA Piedmont, including the=20
Richmond metro area, have medium chances (40-60%) for over one-=20
half inch of ice. The WSSI depicts Major Impacts from Richmond on=20
south along I-95 into NC. While most areas farther north towards=20
the Lower Delaware Valley, Washington D.C. into southern NJ should
largely remain sleet, it may transition to freezing rain for a=20
brief time by Sunday evening. WPC probabilities show low-to-=20
medium chances (30-60%) for over one- tench of an inch of ice=20
accumulations Sunday evening.


Key Messages for this system are linked below (Key Message 2)


Snell/Mullinax



...Extreme Cold & Winter Storm Key Messages are in effect. Please=20
see current Key Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!_vSUFosL_fNE974CSds0-9HtYtuDLS1ao9damo__bVfhY= Taja5j4kl65r1blGHh-4akoePTGVmNbnc9HyIXEP5PejZs$=20

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_2.png__;!!DZ3fjg!_vSUFosL_fNE974CSds0-9HtYtuDLS1ao9damo__bVfhY= Taja5j4kl65r1blGHh-4akoePTGVmNbnc9HyIXELnzOa_o$=20



$$

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FOUS11 KWBC 242008
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
308 PM EST Sat Jan 24 2026

Valid 00Z Sun Jan 25 2026 - 00Z Wed Jan 28 2026


...Ongoing major winter storm to bring crippling icing,=20
significant sleet, and heavy snow from the Southern Rockies/Plains=20
through the Southeast and up the Atlantic Coast into New England...

Meteorological Overview...
Forecast remains on track as a massive winter storm, set to=20
produce a swath of heavy snow, significant sleet, and dangerous ice accumulations, continues across the Southern Plains and begins to=20
expand into the Ohio and Tennessee Valleys this afternoon. By=20
tonight, wintry precipitation is expected to lift into the Mid-=20
Atlantic, and reach New England on Sunday. By the time this event=20
winds down late Monday, it will leave a trail of more than 2000=20
miles of wintry precipitation, in a nearly continuous path, from=20
New Mexico to Maine.

The driver of this event will be the interaction of a northern
stream trough diving out of Canada with a southern stream impulse
ejecting from near Baja California. As these features move eastward
through the weekend and interact into a more amplified and larger
trough over the eastern CONUS, impressive subtropical moisture=20
will spread east/northeast both from the Pacific and the Gulf, with
IVT exceeding the 97th climatological percentile according to
NAEFS. The rich moisture from the south will accompany strong=20
850-700mb WAA that results in classic over-runing along an area of=20
850-700mb FGEN stretching from atop the Southern Plains to the TN=20
VLY and southern Mid-Atlantic by tonight, reaching New England
Sunday, and then finally exiting the Atlantic Coast on Monday. In
addition to the classic overrunning/WAA precipitation, the
placement of the upper jet as it strengthens and pivots poleward,
will support intense bands of snowfall (cross sections suggest a
high threat for CSI and even potential CI within the strongest WAA)
which will support snowfall rates of 1-2+"/hr at times where it is
all snow, and intense sleet/freezing rain rates in mixed zones.

Farther to the east, an intense CAD (Cold Air Damming) signature=20
will develop east of the Appalachians, with intense dewpoint
depressions of 20-30F during precipitation overrunning. While it
will take a while to saturate this to result in precipitation at
the surface, the intensity of this high with cold isallobaric
drainage aided both by mid-level confluence to the north and
precipitation falling into this wedge will enhance the CAD and
result in long duration mixed precipitation as the WAA pushes a
warm nose aloft (generally 800-700mb). This will support heavy
icing and sleet lifting northward into the Mid-Atlantic on Sunday,
and potentially as far as the south coast of New England as well.

With intense IVT pushing PWs to above the 99th percentile, there
will be plentiful moisture to work with everywhere from Texas
through New England. This will support heavy precipitation
accumulations regardless of p-type, so substantial impacts are
expected for a large swath of the nation. The heaviest snow is
expected from the Ohio Valley into the Northeast (more outlined
below), but an impressive jet-forced band of snow is also likely
from the Texas Panhandle through the Mid-Mississippi Valley.
Farther south, crippling icing is expected for parts of
AR/LA/MS/TN, as well as the Carolinas, with exceptional sleet
accumulations of several inches progged in between the snow and ice
from Arkansas through Kentucky, and then for portions of the Mid-
Atlantic as well.\


Heavy Snow/Sleet...
Snow will be winding down across the Southern Plains after 00Z=20
this evening (the start of the forecast period) but remain across=20
NM and of course farther east into AR/MO. This still supports an=20 astonishingly long swath of >6" of snowfall from NM to ME.=20

=46rom the Southern Plains through the Ohio Valley, 72-hr WPC
probabilities (so the entire forecast period although snowfall
should generally be a 24-hr period, a heavy band of snowfall on the
NW side of the low and within the strengthening jet streak will
support 1+"/hr snowfall as reflected by the WPC prototype snowband
tool. With this band likely translating along its long axis, heavy
snowfall will have a temporal extent sufficient for more than 8
inches (30-50% chance from the TX Panhandle through SW MO,
increasing to 90%+ in the Ohio Valley where more than 12 inches is
also likely (50-70% chance) before snow wanes from SW to NE on
Sunday. Locally 15+ inches is possible across southern OH.=20

The heaviest snow is likely from Pennsylvania through New England
where p-type changes are not likely. This is also where the longest
duration of heavy snowfall within both WAA banded structures and
then potentially a more pivoting/translating band will develop as
secondary low pressure skirts off the Mid-Atlantic coast and just
inside the Benchmark (40N/70W). This will support a longer
duration of 1-2+"/hr snowfall, and WPC 72-hr probabilities reach
above 70% for 12+ inches, and locally as much as 2 feet is possible
(especially in the Worcester Hills, Berkshires, and Catskills, as
well north of Boston along the coastal front) where WPC
probabilities for 24" are 10-30%. However, this will be a
widespread 12+" snowfall event for most of southern and central New
England as well as PA.

In addition, with the intense WAA, a warm nose aloft (generally
800-700mb) will gradually create a warm nose above 0C shifting
through the Mid-Atlantic, with additional warm nose/sleet impacts
expected from AR and into TN and KY. The cold depth below this warm
nose appears to be in many places above the 75th-90th percentile
for freezing rain, indicating primary sleet for these areas as
p-type transition occurs, with significant sleet accumulations of multiple-inches expected. This will result in tremendous impacts to
travel in these areas.

The WSSI shows widespread Major Impacts (considerable disruptions
to daily life: dangerous to impossible driving conditions,=20
widespread closures, and disruptions to infrastructure) from the TX
Panhandle on east to the Ozarks, through the OH Valley, and all the
way to New England. Every major market along the I-95 metropolitan
corridor (Washington D.C. to Boston and even as far north as
Portland, ME) are expecting major impacts due to snow. The=20
D.C/Baltimore area on north to Philly and NYC are likely to see=20
some inclusion of sleet, but it will still result in significant=20
impacts when accounting for heavy snowfall that is expected to
exceed warning criteria (5-6"). A reminder that bitterly cold=20
temperatures will follow in wake of this storm through the middle=20
of next week throughout the eastern U.S., so snow/sleet impacts=20
will linger for many days even after precipitation ends.


Freezing Rain...
The most lasting impact will come as a result of significant to=20
locally catastrophic ice accumulations due to prolonged periods of=20
freezing rain. Just like the swath of >6" of snowfall, the areal=20
coverage of high chances (>50%) in WPC's ice probabilities=20
exceeding one-quarter inch of ice accumulation is expansive from=20
eastern TX through southern KY, with a secondary area east of the=20
Cumberland Gap from northern GA through southeast VA and including=20
much of the Carolinas. In these regions, at least 0.25" of ice is=20
expected to be widespread, with a more narrow corridor embedded=20
within of at least 0.5" (50-90%), highest in northern MS and=20
western TN, but some higher potential also exists in GA/SC where=20
locally more than 1 inch (a catastrophic accumulation for damage=20
and prolonged impacts of a week or more) is possible (10-30%=20
chance).

For LA, MS, TN, this ice accumulation is "additional" beyond what
will occur before 00Z (6pm CST), so local amounts above 1" are
actually expected to be more widespread than the updated
probabilities suggest. This produces a 20-40% chance of Extreme
impacts (extensive and widespread disruptions to infrastructure)
and these impacts could linger for a week or more where icing is
most significant. With very cold weather in place, this will become
a life-threatening situation, with potentially impossible travel
due to downed trees and power lines.


Key Messages for this system are linked below (Key Message 2).
Key messages for the widespread extreme cold are linked below as
well (Key Message 1).


...Great Lakes...
Day 3...

Broad cyclonic flow will persist across the east, but an embedded
shortwave within this trough will dig out of Alberta Monday night
and then cross the Great Lakes from northwest to southeast during
Tuesday. This will enhance CAA, leading to another round of lake
effect snow (LES), although the duration and intensity of this
event should be modest overall, some moderate accumulations are
still expected beginning D3 /00Z Tuesday to 00Z Wednesday/ and
lingering beyond this forecast period. LES from Lake Erie should be
minimal as that lake is now ice covered according to GLERL, but
elsewhere, ***WPC probs...heaviest***


Snell/Weiss


...Winter Storm Key Messages are in effect. Please see current=20
Key Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!5yyp-eYgnqjdhXbnMGZ5F6MbfMH3V2jDjKFhtuPp72HzG= v1utrZAGBCuWMZw740nbStEiOYlG4pGhUeyanMrSk83qWE$=20

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_2.png__;!!DZ3fjg!5yyp-eYgnqjdhXbnMGZ5F6MbfMH3V2jDjKFhtuPp72HzG= v1utrZAGBCuWMZw740nbStEiOYlG4pGhUeyanMrxvhmuX8$=20



$$

=3D =3D =3D
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--- SBBSecho 3.28-Linux
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FOUS11 KWBC 242013
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
313 PM EST Sat Jan 24 2026

Valid 00Z Sun Jan 25 2026 - 00Z Wed Jan 28 2026


...Ongoing major winter storm to bring crippling icing,=20
significant sleet, and heavy snow from the Southern Rockies/Plains=20
through the Southeast and up the Atlantic Coast into New England...

Meteorological Overview...
Forecast remains on track as a massive winter storm, set to=20
produce a swath of heavy snow, significant sleet, and dangerous ice accumulations, continues across the Southern Plains and begins to=20
expand into the Ohio and Tennessee Valleys this afternoon. By=20
tonight, wintry precipitation is expected to lift into the Mid-=20
Atlantic, and reach New England on Sunday. By the time this event=20
winds down late Monday, it will leave a trail of more than 2000=20
miles of wintry precipitation, in a nearly continuous path, from=20
New Mexico to Maine.

The driver of this event will be the interaction of a northern
stream trough diving out of Canada with a southern stream impulse
ejecting from near Baja California. As these features move eastward
through the weekend and interact into a more amplified and larger
trough over the eastern CONUS, impressive subtropical moisture=20
will spread east/northeast both from the Pacific and the Gulf, with
IVT exceeding the 97th climatological percentile according to
NAEFS. The rich moisture from the south will accompany strong=20
850-700mb WAA that results in classic over-runing along an area of=20
850-700mb FGEN stretching from atop the Southern Plains to the TN=20
VLY and southern Mid-Atlantic by tonight, reaching New England
Sunday, and then finally exiting the Atlantic Coast on Monday. In
addition to the classic overrunning/WAA precipitation, the
placement of the upper jet as it strengthens and pivots poleward,
will support intense bands of snowfall (cross sections suggest a
high threat for CSI and even potential CI within the strongest WAA)
which will support snowfall rates of 1-2+"/hr at times where it is
all snow, and intense sleet/freezing rain rates in mixed zones.

Farther to the east, an intense CAD (Cold Air Damming) signature=20
will develop east of the Appalachians, with intense dewpoint
depressions of 20-30F during precipitation overrunning. While it
will take a while to saturate this to result in precipitation at
the surface, the intensity of this high with cold isallobaric
drainage aided both by mid-level confluence to the north and
precipitation falling into this wedge will enhance the CAD and
result in long duration mixed precipitation as the WAA pushes a
warm nose aloft (generally 800-700mb). This will support heavy
icing and sleet lifting northward into the Mid-Atlantic on Sunday,
and potentially as far as the south coast of New England as well.

With intense IVT pushing PWs to above the 99th percentile, there
will be plentiful moisture to work with everywhere from Texas
through New England. This will support heavy precipitation
accumulations regardless of p-type, so substantial impacts are
expected for a large swath of the nation. The heaviest snow is
expected from the Ohio Valley into the Northeast (more outlined
below), but an impressive jet-forced band of snow is also likely
from the Texas Panhandle through the Mid-Mississippi Valley.
Farther south, crippling icing is expected for parts of
AR/LA/MS/TN, as well as the Carolinas, with exceptional sleet
accumulations of several inches progged in between the snow and ice
from Arkansas through Kentucky, and then for portions of the Mid-
Atlantic as well.\


Heavy Snow/Sleet...
Snow will be winding down across the Southern Plains after 00Z=20
this evening (the start of the forecast period) but remain across=20
NM and of course farther east into AR/MO. This still supports an=20 astonishingly long swath of >6" of snowfall from NM to ME.=20

=46rom the Southern Plains through the Ohio Valley, 72-hr WPC
probabilities (so the entire forecast period although snowfall
should generally be a 24-hr period, a heavy band of snowfall on the
NW side of the low and within the strengthening jet streak will
support 1+"/hr snowfall as reflected by the WPC prototype snowband
tool. With this band likely translating along its long axis, heavy
snowfall will have a temporal extent sufficient for more than 8
inches (30-50% chance from the TX Panhandle through SW MO,
increasing to 90%+ in the Ohio Valley where more than 12 inches is
also likely (50-70% chance) before snow wanes from SW to NE on
Sunday. Locally 15+ inches is possible across southern OH.=20

The heaviest snow is likely from Pennsylvania through New England
where p-type changes are not likely. This is also where the longest
duration of heavy snowfall within both WAA banded structures and
then potentially a more pivoting/translating band will develop as
secondary low pressure skirts off the Mid-Atlantic coast and just
inside the Benchmark (40N/70W). This will support a longer
duration of 1-2+"/hr snowfall, and WPC 72-hr probabilities reach
above 70% for 12+ inches, and locally as much as 2 feet is possible
(especially in the Worcester Hills, Berkshires, and Catskills, as
well north of Boston along the coastal front) where WPC
probabilities for 24" are 10-30%. However, this will be a
widespread 12+" snowfall event for most of southern and central New
England as well as PA.

In addition, with the intense WAA, a warm nose aloft (generally
800-700mb) will gradually create a warm nose above 0C shifting
through the Mid-Atlantic, with additional warm nose/sleet impacts
expected from AR and into TN and KY. The cold depth below this warm
nose appears to be in many places above the 75th-90th percentile
for freezing rain, indicating primary sleet for these areas as
p-type transition occurs, with significant sleet accumulations of multiple-inches expected. This will result in tremendous impacts to
travel in these areas.

The WSSI shows widespread Major Impacts (considerable disruptions
to daily life: dangerous to impossible driving conditions,=20
widespread closures, and disruptions to infrastructure) from the TX
Panhandle on east to the Ozarks, through the OH Valley, and all the
way to New England. Every major market along the I-95 metropolitan
corridor (Washington D.C. to Boston and even as far north as
Portland, ME) are expecting major impacts due to snow. The=20
D.C/Baltimore area on north to Philly and NYC are likely to see=20
some inclusion of sleet, but it will still result in significant=20
impacts when accounting for heavy snowfall that is expected to
exceed warning criteria (5-6"). A reminder that bitterly cold=20
temperatures will follow in wake of this storm through the middle=20
of next week throughout the eastern U.S., so snow/sleet impacts=20
will linger for many days even after precipitation ends.


Freezing Rain...
The most lasting impact will come as a result of significant to=20
locally catastrophic ice accumulations due to prolonged periods of=20
freezing rain. Just like the swath of >6" of snowfall, the areal=20
coverage of high chances (>50%) in WPC's ice probabilities=20
exceeding one-quarter inch of ice accumulation is expansive from=20
eastern TX through southern KY, with a secondary area east of the=20
Cumberland Gap from northern GA through southeast VA and including=20
much of the Carolinas. In these regions, at least 0.25" of ice is=20
expected to be widespread, with a more narrow corridor embedded=20
within of at least 0.5" (50-90%), highest in northern MS and=20
western TN, but some higher potential also exists in GA/SC where=20
locally more than 1 inch (a catastrophic accumulation for damage=20
and prolonged impacts of a week or more) is possible (10-30%=20
chance).

For LA, MS, TN, this ice accumulation is "additional" beyond what
will occur before 00Z (6pm CST), so local amounts above 1" are
actually expected to be more widespread than the updated
probabilities suggest. This produces a 20-40% chance of Extreme
impacts (extensive and widespread disruptions to infrastructure)
and these impacts could linger for a week or more where icing is
most significant. With very cold weather in place, this will become
a life-threatening situation, with potentially impossible travel
due to downed trees and power lines.


Key Messages for this system are linked below (Key Message 2).
Key messages for the widespread extreme cold are linked below as
well (Key Message 1).


...Great Lakes...
Day 3...

Broad cyclonic flow will persist across the east, but an embedded
shortwave within this trough will dig out of Alberta Monday night
and then cross the Great Lakes from northwest to southeast during
Tuesday. This will enhance CAA, leading to another round of lake
effect snow (LES), although the duration and intensity of this
event should be modest overall, some moderate accumulations are
still expected beginning D3 /00Z Tuesday to 00Z Wednesday/ and
lingering beyond this forecast period. LES from Lake Erie should be
minimal as that lake is now ice covered according to GLERL, but
elsewhere, WPC probabilities are moderate for 4+ inches near the
Tug Hill Plateau, and moderate (10-50%)for 2+ inches along the=20
western shore of the L.P. of MI as well as parts of the U.P.


Snell/Weiss



...Winter Storm Key Messages are in effect. Please see current=20
Key Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!5W-O6S2TsavdXtQOUAK8oUfK4CWv9hDLB6maEn-RBEC8z= dxGx2_1hRti8HNuSE65ZONdrM6PSUgE9zjorHLbn-2g7N0$=20

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_2.png__;!!DZ3fjg!5W-O6S2TsavdXtQOUAK8oUfK4CWv9hDLB6maEn-RBEC8z= dxGx2_1hRti8HNuSE65ZONdrM6PSUgE9zjorHLbAtBCRDQ$=20



$$

=3D =3D =3D
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FOUS11 KWBC 250741
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
241 AM EST Sun Jan 25 2026

Valid 12Z Sun Jan 25 2026 - 12Z Wed Jan 28 2026


...Ongoing major winter storm to bring crippling icing,=20
significant sleet, and heavy snow from the Southern Rockies/Plains=20
through the Southeast and up the Atlantic Coast into New England...

Meteorological Overview...
Forecast remains on track as a massive winter storm is underway
across a significant portion of the country, currently extending=20
from the southern Rockies to the Mid-Atlantic early this morning.
By the start of the forecast period (12z Sun), widespread moderate
to heavy snow, sleet, and freezing rain is expected to span from=20
New Mexico to New York and continue to primarily impact regions=20
from the Ohio/Tennessee valleys and Mid-Atlantic to New England
through the overnight hours tonight. This event is forecast to=20
gradually wane across New England and the Interior Northeast on=20
Monday.

The driver of this winter storm is the interaction of a northern=20
stream trough diving out of the north-central U.S. this morning
along with a few southern stream impulses ejecting from the
southern Rockies and Plains. As these features accelerate eastward
today and interact into a more amplified and larger trough over=20
the central CONUS tonight, impressive subtropical moisture will
continue spreading east/northeast both from the Pacific and the=20
Gulf, with IVT exceeding the 97.5th climatological percentile=20
according to NAEFS. The rich moisture from the south will accompany
strong 850-700mb WAA that results in classic over- running along=20
an area of 850-700mb FGEN stretching from atop the Mid-MS and OH/TN
VLY to the Mid- Atlantic this morning, reaching New England this=20
evening and then finally exiting the Atlantic Coast on Monday. In=20
addition to the classic overrunning/WAA precipitation, the=20
placement of the upper jet as it strengthens and pivots poleward,=20
will support intense bands of snowfall (cross sections suggest a=20
high threat for CSI and even potential CI within the strongest WAA)
which will support snowfall rates of 1-2+"/hr at times where it is
all snow, and intense sleet/freezing rain rates in mixed zones.

Farther to the east, the intense CAD (Cold Air Damming) signature=20=20
east of the Appalachians will only slightly retreat through
tonight. With rapid warming aloft due to increasing southerly 850mb
winds over 50 kts and subfreezing temperatures remaining in the=20
low- levels, sleet is expected to be as far north as southern MD by
12z this morning and continuing marching northward through the day
as far as the southern New England coastline. This will cut down on
snowfall totals along I-95 from Washington D.C. to NYC, and will
also increase the potential for ptype to turn towards dangerous
freezing rain by late this afternoon.

With intense IVT pushing PWs to above the 99th percentile, there
will be plentiful moisture to work with everywhere from the OH VLY
through New England. This will support heavy precipitation=20
accumulations regardless of p-type, so substantial impacts are=20
expected for a large swath of the nation. The heaviest snow is=20
expected from the Ohio Valley into the Northeast (more outlined=20
below). Farther south, crippling icing is expected for parts of=20
AR/LA/MS/TN early today, as well as the Carolinas and Virginia
through tonight, with exceptional sleet accumulations of several=20
inches progged in between the snow and ice from Arkansas through=20
Kentucky, and then for portions of the Mid- Atlantic as well.


Heavy Snow/Sleet...
Snow will be winding down across the Southern Plains and Mid-MS VLY
by 12z this morning, but continues just east through the OH VLY. This
still supports an long swath of >6" of snowfall from IN to ME and
an increasing potential for >18" across the Interior Northeast and
New England.

48-hr WPC probabilities (most snow occurring within the first=20
24-hr period), are high (>70%) for an additional 8"+ from central=20
OH through central ME and most of New England. Probabilities for=20
18"+ have increased and are 50-80% across Upstate NY through much=20
of New England as far north as central VT/NH. A heavy band of=20
snowfall on the NW side of the low and within the strengthening jet
streak will support 1+"/hr snowfall across the Ohio Valley through
this afternoon as reflected by the WPC prototype snowband tool.=20
With this band likely translating along its long axis, heavy=20
snowfall will have a temporal extent sufficient for more than 8=20
inches. Locally 15+ inches is possible across southern OH.=20

The heaviest snow from this event is likely across New England and
the Interior Northeast where p-type changes are not likely. This=20
is also where the longest duration of heavy snowfall within both=20
WAA banded structures and then potentially a more=20
pivoting/laterally translating band will develop as secondary low=20
pressure skirts off the Mid- Atlantic coast and just inside the=20
Benchmark (40N/70W). This will support a longer duration of=20
2+"/hr snowfall, and WPC 48-hr probabilities reach above 90% for=20
12+ inches, and locally as much as 2 feet is possible (especially=20
in the Worcester Hills, Berkshires, and Catskills, as well north of
Boston along the coastal front) where WPC probabilities for 24"=20
are 20-40%. WPC's Snowband Probability Tracker (SPT) using the 00z
HREF is very impressive for 1-2"+/hr rates around 18Z near=20
northern NJ and eventually across New England beginning around 21Z
and lasting across eastern New England until 06Z tonight.=20
Regarding coverage of heavy snow, this will be a widespread 12"+=20
snowfall event for most of southern and central New England as well
as central/northern PA.

In addition, with the intense WAA, a warm nose aloft (generally
800-700mb) will gradually create a warm nose above 0C shifting
through the Mid-Atlantic. The cold depth below this warm nose=20
appears to be in many places above the 75th-90th percentile for=20
freezing rain, indicating primary sleet for these interior areas=20
as p-type transition occurs, with significant sleet accumulations=20
of multiple-inches expected. This will result in tremendous impacts
to travel in these areas.

The WSSI shows widespread Major Impacts (considerable disruptions
to daily life: dangerous to impossible driving conditions,=20
widespread closures, and disruptions to infrastructure) from the=20
OH VLY to New England. Every major market along the I-95=20
metropolitan corridor (Washington D.C. to Boston and even as far=20
north as Portland, ME) are expecting major impacts due to snow
amounts. The D.C/Baltimore area on north to Philly and NYC are=20
likely to see some inclusion of sleet and potentially some freezing
rain, but it will still result in significant impacts when=20
accounting for heavy snowfall that is expected to exceed warning=20
criteria (5-6"). Gusty winds increasing with the developing=20
surface low off the Mid-Alantic coast may also lead to a brief=20
period of near-blizzard conditions across eastern New England,=20
including Boston, late tonight. A reminder that bitterly cold=20
temperatures will follow in wake of this storm through the middle=20
of next week throughout the eastern U.S., so snow/sleet impacts=20
will linger for many days even after precipitation ends.

Freezing Rain...
The most lasting impact will come as a result of significant to=20
locally catastrophic ice accumulations due to prolonged periods of=20
freezing rain. Just like the swath of >6" of snowfall, the areal=20
coverage of impactful freezing rain remains expansive across the=20
Mid- South, where the event concludes by midday today and a=20
secondary area east of the Cumberland Gap from northern GA through=20
central VA and southern MD, including much of the Carolinas. In=20
these regions, at least 0.25" of total ice is expected to be=20
widespread, with a more narrow corridor embedded within of at least
an additional 0.5" (30-60%), highest today across the NC Piedmont
into south-central VA. This amount of freezing rain can create
widespread power outages and tree damage, as well as treacherous to
impossible travel at times.

For LA, MS, TN, ice accumulation is "additional" beyond what will=20
occur before 12Z (6am CST), so local amounts above 1" are actually
expected to be much more widespread than the very low=20
probabilities suggest for solely today's precipitation. The=20
greatest additional icing after 12Z today is located across the=20
Mid- Atlantic, where up to 0.5" is possible. With very cold weather
in place, this will become a life- threatening situation where=20
freezing rain amounts are highest (including the Lower MS VLY and=20
Mid-South) with potentially impossible travel due to downed trees=20
and power lines.


Key Messages for this system are linked below (Key Message 2).
Key messages for the widespread extreme cold are linked below as
well (Key Message 1).


...Great Lakes...
Days 2-3...

Broad cyclonic flow will persist across the east, but an embedded
shortwave within this trough will dig out of Alberta Monday night
and then cross the Great Lakes from northwest to southeast during
Tuesday. This will enhance CAA, leading to another round of lake
effect snow (LES), although the duration and intensity of this
event should be modest overall, some moderate accumulations are
still expected beginning D2-3 and lingering beyond this forecast=20
period. LES from Lake Erie should be minimal as that lake is now=20
ice covered according to GLERL and should continue to see ice
thicken with very cold temperatures in place, but elsewhere, WPC=20 probabilities are high for 4+ inches near the Tug Hill Plateau.


Snell/Weiss




...Winter Storm Key Messages are in effect. Please see current=20
Key Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!9sseXzdxj0AGHqtE9PxBDvpaCHTgyf0kBlV0VQClBi97u= cbSjEzZJILpGM3a97dsD08_MPYg2KvCXzcmJFn55hXmNHY$=20

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_2.png__;!!DZ3fjg!9sseXzdxj0AGHqtE9PxBDvpaCHTgyf0kBlV0VQClBi97u= cbSjEzZJILpGM3a97dsD08_MPYg2KvCXzcmJFn5V8ppWtM$=20



$$

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FOUS11 KWBC 251820
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
120 PM EST Sun Jan 25 2026

Valid 00Z Mon Jan 26 2026 - 00Z Thu Jan 29 2026


...Mid-Atlantic and Northeast...
Days 1-2...

The expansive winter storm will wind down across the Central
Plains and Mid-South today, but significant impacts will persist
across the Ohio Valley, Mid-Atlantic, and Northeast tonight and
Monday.

This morning, the GOES-E water vapor imagery tells the take, with
an impressive plume of moisture stretching from Texas into southern
Canada, with a clear baroclinic leaf expanding over the TN/OH
Valleys. The upper low is spinning over TX and this will lift
northward into the Ohio Valley today, while secondary low pressure
development occurs off the Mid-Atlantic coast this afternoon. This
secondary low pressure will become dominant and strengthen as it
tracks south of New England, with the most significant winter
weather and impacts shifting into New England tonight and Monday.
The trailing upper trough will move across the Great Lakes Monday,
helping to drive an inverted trough back across New England even as
the primary low departs, and light although the heaviest snow
should end Monday night, light snow may persist in this area into
Tuesday morning.=20

This evolution will result in impressive additional snow amounts
(after 00Z this evening) from the higher terrain of WV/PA northeast
through Upstate NY and all of New England. The heaviest snowfall is
expected across Upstate NY and New England where WPC probabilities
indicate a high risk (>90%) for at least 8 inches, with 12-18"
possible (30-50% chance) for the Greens, Whites, and coastal SW=20
Maine/far northern MA thanks to a coastal front evolution. Snowfall
rates will be extreme at times, potentially reaching 2-3"/hr as=20
progged by the WPC prototype snowband tool due to strong WAA=20
overlapping fgen which may result in CSI/CI (and possible=20
thundersnow). The intense WAA in the 850-700mb will drive a warm=20
nose above 0C as far north as coastal CT/RI/Cape Cod, so some=20
transition to sleet is likely, but otherwise a very cold airmass=20
will allow SLRs to be above climo (but dropping during the event)=20
which will help that efficient snow growth. The DGZ is quite=20
elevated, so the best ascent will not cross-hatch into the snow=20
growth region in most areas, but nevertheless, robust moisture on=20
IVT exceeding the 90th percentile will wring out to this heavy=20
snow, and it is possible some 48-hr total snowfall will reach more=20
than 2 feet in parts of New England, with widespread 6-12" covering
most of the Mid-Atlantic, Ohio Valley, and rest of the Northeast=20
before this event winds down.

Although most of the accumulation will occur by 12Z Monday, the
aforementioned inverted trough linking back to the upper low may
allow for wrap-around snowfall to linger much of Monday and into
Monday night adding a few more inches of cold fluffy snow to the
area, especially New England and Upstate NY. WSSI-P indicates
continues high probabilities (>80%) for major impacts, and the I-95
corridor between NYC and Portland, ME will be treacherous through
Monday.

Farther south, freezing rain will continue for parts of the Mid-
Atlantic, especially northern NC, southeast VA, and potentially
along the I-95 corridor as far north as NYC. While additional
freezing rain amounts are expected to be modest as precip begins to
wind down (WPC probabilities suggest a 50-70% chance of at least
0.1" of ice), this will be on top of prior icing to enhance impacts
including treacherous travel and power outages. With extremely cold temperatures likely after this storm persisting for many days, any
power outages will become a life-threatening situation for parts of
the Mid-Atlantic states.


...Great Lakes...
Days 1-3...

Broad cyclonic flow will persist across the east, and multiple
embedded shortwaves will ride through this trough out of Canada,
each one acting to reinforce cold advection (CAA) across the Great
Lakes to support rounds of lake effect snow (LES). While GLERL
indicates that water temperatures are cooling, Lake Erie is
entirely ice covered, and with the very cold temperatures this week
continuing, additional ice cover is expected. However, there
should still be sufficient instability and moisture to support LES
each day through the forecast period. LES is not expected to be
extremely intense, although will be efficient downstream of Lake
Ontario towards the Tug Hill Plateau at times, and it is this area
that is expected to receive the heaviest LES. WPC probabilities for
all 3 days indicate a high chance (>70%) for at least 8 inches east
of Lake Ontario, with lower probabilities for 8+ inches (10-30%
chance) southeast of Lake Michigan and across the eastern U.P. on
the south shore of Lake Superior.

Weiss



...Winter Storm Key Messages are in effect. Please see current=20
Key Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!5X0xN7MdHtpiv0Oq5XxTtzmHSf-mjyyl5Z8e4q_9Z6UZb= c44QpuSi4xTywscDvjJby3zed3keoBg7ZLpxNDxroebvd4$=20

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_2.png__;!!DZ3fjg!5X0xN7MdHtpiv0Oq5XxTtzmHSf-mjyyl5Z8e4q_9Z6UZb= c44QpuSi4xTywscDvjJby3zed3keoBg7ZLpxNDxHkG_Cm8$=20



$$

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FOUS11 KWBC 260707
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
207 AM EST Mon Jan 26 2026

Valid 12Z Mon Jan 26 2026 - 12Z Thu Jan 29 2026


...New England...
Day 1...

The major winter storm that swept over the Nation the last few
days will continue to gradually exit the Northeast today, with
lingering additional snowfall across parts of New England. By the
start of the forecast period (12z Mon), the primary surface low
will be sliding east into the open Atlantic and only provide for
some favorable ocean-enhanced snow from the south coast of ME to
eastern MA. Otherwise, mostly light to moderate snow will be
associated with a weakening 850mb low tracking across northern New
England. Additional snowfall amounts through tonight are expected
to range from 3-5", with the highest probabilities (50-80%) for
greater than 4" extending from the northern coast of MA to eastern
ME. Storm total snowfall amounts from Sunday through the D1 period
are expected to exceed 20" across parts of New England.


...Great Lakes...
Days 1-3...

Broad cyclonic flow will persist across the east, and multiple
embedded shortwaves will ride through this trough out of Canada,
each one acting to reinforce cold advection (CAA) across the Great
Lakes to support rounds of lake effect snow (LES). While GLERL
indicates that water temperatures are cooling, Lake Erie is
entirely ice covered, and with the very cold temperatures this week
continuing, additional ice cover is expected. However, there
should still be sufficient instability and moisture to support LES
each day through the forecast period. LES is not expected to be
extremely intense, although will be efficient downstream of Lake
Ontario towards the Tug Hill Plateau at times, and it is this area
that is expected to receive the heaviest LES. WPC probabilities for
all 3 days indicate a high chance (>80%) for at least 12 inches
east of Lake Ontario, with lower probabilities for 8+ inches
(30-60% chance) east of Lake Michigan and across the eastern U.P.
on the south shore of Lake Superior.


Snell



$$

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FOUS11 KWBC 262022
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
322 PM EST Mon Jan 26 2026

Valid 00Z Tue Jan 27 2026 - 00Z Fri Jan 30 2026


...New England...
Day 1...

The final bands of the major winter storm shift east from New
England this evening. A couple additional inches are possible after
00Z over much of Maine down through the Mass coast.


...Great Lakes...
Days 1-3...

Broad cyclonic flow and trough passages persist across the Great
Lakes as low pressure over Hudson Bay shifts south over Ontario
through Thursday. These will produce rounds of lake effect snow=20
(LES) particularly starting Tuesday behind a notable upper trough
passage. According to GLERL, Lake Erie is essentially ice=20
covered, so available moisture will be limited there while Lakes=20
Superior and Ontario remain largely. Westerly flow allows Day 2/3=20
PWPF for >6" are over 50% in the Tug Hill and just Day 2 for the
eastern U.P. of Michigan.


...Cascades...
Days 2/3...

The next trough axis shunts the powerful ridge east Tuesday night
with precip over the WA Cascades then through Thursday. Snow levels
rise from 4000 to 5000ft over the WA Cascades Wednesday through
Thursday. PWPF for >6" is 40-70% above the snow level (above pass
level) by Thursday.


The probability for significant icing is less than 10 percent.



Jackson




...Extreme Cold Key Messages are linked below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!-0TZxpay_jM8Z4Q34rmMmud52o6t8jkHOE9b3VqfOemR-= ZzRDBrxLmQXLRJn74txeFUITeYsrY6M3nwWigr62iJQsj4$=20



$$

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FOUS11 KWBC 270733
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
233 AM EST Tue Jan 27 2026

Valid 12Z Tue Jan 27 2026 - 12Z Fri Jan 30 2026


...Great Lakes...
Days 1-3...

Broad cyclonic flow and trough passages persist across the Great
Lakes as low pressure over Hudson Bay shifts south over Ontario
through Thursday. These will produce rounds of lake effect snow=20
(LES) beginning today behind a notable upper trough passage. 850mb
temperatures will remain quite cold during this period, with
temperatures around -18 to -24C, and below the 10th climatological
percentile. According to GLERL, Lake Erie is essentially ice=20
covered, so available moisture will be limited there while Lakes=20
Superior and Ontario remain largely open. Westerly flow will
continue across the Lower Great Lakes through Thursday night, with
northerly flow more likely on Day 3 across the Upper Great Lakes,
This allows Days 1-3 PWPF for >8" over 50% in the Tug Hill and for
the eastern U.P. of Michigan. The heaviest snowfall is no doubt
most likely downwind of Lake Ontario and the Tug Hill, where 50-60% probabilities for >18" reach the shoreline of Oswego county.


...Cascades...
Days 2/3...

The next trough axis to near the Pacific Northwest shunts the=20
powerful western ridge eastward Tuesday night, with precip over=20
the WA Cascades then through Thursday. Snow levels rise from 4000=20
to 5000ft over the WA Cascades Wednesday through Thursday. PWPF for

6" is 40-70% above the snow level (above pass level) by Thursday.

The probability for significant icing is less than 10 percent.



Snell





...Extreme Cold Key Messages are in effect. Please see current Key
Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!8NunqgJMY9ONsq94cDZxgfNTy_qFZpb-PYrxM2rTB5EIS= h2M4WxUege40SO-B-z28uH25Ynjwag2vrjv-7YR7oHbKF4$=20



$$

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FOUS11 KWBC 271931
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
231 PM EST Tue Jan 27 2026

Valid 00Z Wed Jan 28 2026 - 00Z Sat Jan 31 2026


...Great Lakes...
Days 1-3...

The seemingly endless cyclonic flow that has kept the LES machine=20
cranking over snow belts of the Great Lakes looks to continue
through the remainder of the work-week. Frigid 850mb temperatures=20
will persist with temperatures around -18 to -24C, which are below
the 10th climatological percentile. According to GLERL, Lake Erie=20
is essentially ice covered, so available moisture will be limited=20
there while Lakes Superior and Ontario remain largely open. W-NWrly
low-level winds will continue through Wednesday before the approach
of a sharp 500mb shortwave pivots through and shifts winds more out
of the N-NNW by Thursday. Northerly flow continues Friday as high
pressure builds in over the Northern Plains. 72-hour WPC
probabilities depict high chances (>70%) for snowfall totals >4"
over the northern tier of the Michigan U.P. and down wind of Lake=20
Ontario to the south of an over the Tug Hill. The area with the=20
best odds of seeing over a foot of snow over the next few days are=20
near the Oswego, NY area where WPC probabilities for over a foot of
snow are in the moderate range of probabilities (40-60%).=20


...Cascades & Olympics...
Days 1-3...

A series of storm systems tracking into the Gulf of Alaska will
direct rounds of moisture and WAA at western WA through the
remainder of the week. Strong upslope flow should support locally
heavy snowfall totals as low as 4,000ft, but most heavy snow will=20
reside in the more remote areas above 5,000ft. Snow levels rise=20
from 4000 to 5000ft over the WA Cascades Wednesday through=20
Thursday. By Friday, snow levels approach 6,000ft by Friday in
western WA. WPC probabilities for >4" is high (>70%) around Stevens
Pass, but lighter accumulations around Snoqualmie are anticipated
at this moment given the higher snow levels.

...Northern & Central Plains...
Days 2-3...

A weak Pacific shortwave trough tracking NW-SE will ride along a
nearby 850mb front to support periods of snow from the northern
High Plains on south in the the central High Plains. Snow is not
expected to be overly heavy, although the Black Hills through
orographic lifting may be able to see snowfall amounts surpass 6".
This is supported in WPC probabilities which show moderate-to-high
chances (50-70%) for >4" of snow in the Black Hills, and low
chances (10-30%) in their peaks for >8". Elsewhere, from eastern MT
on south and east through the Missouri River Valley, most snowfall accumulations are likely to range between 1-3". Some hazardous
travel is possible, especially where roads temperatures are at or
below freezing in wake of the recent extreme cold.


...Southern Appalachians & Mid-Atlantic...
Days 3-3.5...

...Confidence In Impactful Snowfall Increasing For the Southern=20
Appalachians and Southern Mid-Atlantic...

To say there remains a large amount of model spread in the
potential winter storm beyond Day 3 would be an understatement. In
the past 24 hours, ensemble guidance have flipped camps to where
the GEFS are the snowier members, CMCE are more in the middle, and
the EC-EPS are trending less snowy. It is worth noting that AI=20
ensemble membership are not as snowy as the GEFS, but show a little
more snow than the EC-EPS, making this an interesting test in how=20
the AI ensemble membership performs.=20

Regarding the setup-- WPC Cluster Analysis shows this potential=20
winter storm comes down to several factors: 1) strength of the=20
emerging Great Lakes shortwave trough. 2) speed of the shortwave=20
trough. 3) tilt/amplitude of the shortwave trough as it tracks=20
east. 4) Confluence strength near Nova Scotia. They all work=20
together in an intricate dance that makes for difficulties in=20
modeling. A stronger/slower shortwave can buy time for confluence=20
over New England and Nova Scotia to weaken, giving the shortwave=20
more time to amplify, and allow for closer storm tracks to the=20
coast that bring heavy snow as far west as the I-95 corridor (some=20
GEFS members and some CMCE members). Where the shortwave is=20
stronger but progressive, heavier snowfall occurs but largely=20
closer to the coast and as far west as the NC Piedmont (CMCE=20
members, UK ensembles, split EC/GEFS members). If the shortwave=20
trough is more progressive and cannot separate itself from the=20
larger TPV to the east there is less amplification, it results in=20
a flatter and more positively/tilted shortwave trough, and thus the=20
storm remains largely out at sea (EPS, EC-AIFS ensembles, some=20
GEFS/CMCE members). It is worth noting that, while the EC-AIFS has=20
largely performed well inside of 5 days much of the winter season,=20
the EC-AIFS and ECMWF did suppress the track of the most recent=20
winter storm too much ~4-5 days out before correcting northward=20
inside of 72 hours out.

This setup is highly timing dependent; from the primary shortwave
trough currently east of Hudson Bay, to the interaction/spacing of
the 500mb cyclonic gyres in southeast Canada and south of Iceland
that promote the confluence ahead of the potential storm, to the=20
incoming Pacific shortwaves that track into western Canada and
adjust the strength/position of the western North America ridge.=20
There remain a host of embedded shortwaves that will work together=20
to create a complex storm evolution off the East Coast. Whatever=20
the current model solutions show beyond 72 hours out is unlikely to
be the final product. Expect additional model changes in the=20
coming days. If there is one thing that has increased in confidence
in the past 24 hours, it is the opportunity for coastal flooding=20
and beach erosion along the Mid-Atlantic coast. Please refer to our
"What We know, What We Don't Know" social media post for=20
additional information.

The one thing they do agree on is this upper trough tracks through
the OH Valley Friday afternoon with sufficient PVA and 850-500mb=20
mean layer moisture to support snow from central KY to the southern Appalachians through Friday evening. WPC probabilities do
show increasing chances for at least minor accumulations >2" over
KY and northeast TN, while there are low-chances (10-30%) for
snowfall totals >4" through early Saturday morning in the TN/NC Smokeys
and Blue Ridge of NC. Residents and those traveling to the=20
Carolinas on north up the East Coast will want to continue=20
following the forecasts from WPC and your local NWS WFO for the=20
latest regarding this potential winter storm.=20


The probability for significant icing is less than 10 percent.


Mullinax




...Extreme Cold Key Messages are in effect. Please see current Key
Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!6VI14otitwAAstNrC60qAGwJSrOE6Zf0oLu0MtZRucHys= 6sfDSsnz6A0nRg5hdjsoJ-6sT4HYazaHiiRfGLVWtSFuMg$=20



$$

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FOUS11 KWBC 272009
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
309 PM EST Tue Jan 27 2026

Valid 00Z Wed Jan 28 2026 - 00Z Sat Jan 31 2026


...Great Lakes...
Days 1-3...

The seemingly endless cyclonic flow that has kept the LES machine=20
cranking over snow belts of the Great Lakes looks to continue
through the remainder of the work-week. Frigid 850mb temperatures=20
will persist with temperatures around -18 to -24C, which are below
the 10th climatological percentile. According to GLERL, Lake Erie=20
is essentially ice covered, so available moisture will be limited=20
there while Lakes Superior and Ontario remain largely open. W-NWrly
low-level winds will continue through Wednesday before the approach
of a sharp 500mb shortwave pivots through and shifts winds more out
of the N-NNW by Thursday. Northerly flow continues Friday as high
pressure builds in over the Northern Plains. 72-hour WPC
probabilities depict high chances (>70%) for snowfall totals >4"
over the northern tier of the Michigan U.P. and down wind of Lake=20
Ontario to the south of an over the Tug Hill. The area with the=20
best odds of seeing over a foot of snow over the next few days are=20
near the Oswego, NY area where WPC probabilities for over a foot of
snow are in the moderate range of probabilities (40-60%).=20


...Cascades & Olympics...
Days 1-3...

A series of storm systems tracking into the Gulf of Alaska will
direct rounds of moisture and WAA at western WA through the
remainder of the week. Strong upslope flow should support locally
heavy snowfall totals as low as 4,000ft, but most heavy snow will=20
reside in the more remote areas above 5,000ft. Snow levels rise=20
from 4000 to 5000ft over the WA Cascades Wednesday through=20
Thursday. By Friday, snow levels approach 6,000ft by Friday in
western WA. WPC probabilities for >4" is high (>70%) around Stevens
Pass, but lighter accumulations around Snoqualmie are anticipated
at this moment given the higher snow levels.

...Northern & Central Plains...
Days 2-3...

A weak Pacific shortwave trough tracking NW-SE will ride along a
nearby 850mb front to support periods of snow from the northern
High Plains on south in the the central High Plains. Snow is not
expected to be overly heavy, although the Black Hills through
orographic lifting may be able to see snowfall amounts surpass 6".
This is supported in WPC probabilities which show moderate-to-high
chances (50-70%) for >4" of snow in the Black Hills, and low
chances (10-30%) in their peaks for >8". Elsewhere, from eastern MT
on south and east through the Missouri River Valley, most snowfall accumulations are likely to range between 1-3". Some hazardous
travel is possible, especially where roads temperatures are at or
below freezing in wake of the recent extreme cold.


...Southern Appalachians & Mid-Atlantic...
Days 3-3.5...

...Confidence In Impactful Snowfall Increasing For the Southern=20
Appalachians and Southern Mid-Atlantic...

To say there remains a large amount of model spread in the
potential winter storm beyond Day 3 would be an understatement. In
the past 24 hours, ensemble guidance have flipped camps to where
the GEFS are the snowier members, CMCE are more in the middle, and
the EC-EPS are trending less snowy. It is worth noting that AI=20
ensemble membership are not as snowy as the GEFS, but show a little
more snow than the EC-EPS, making this an interesting test in how=20
the AI ensemble membership performs.=20

Regarding the setup-- WPC Cluster Analysis shows this potential=20
winter storm comes down to several factors: 1) strength of the=20
emerging Great Lakes shortwave trough. 2) speed of the shortwave=20
trough. 3) tilt/amplitude of the shortwave trough as it tracks=20
east. 4) Confluence strength near Nova Scotia. They all work=20
together in an intricate dance that makes for difficulties in=20
modeling. A stronger/slower shortwave can buy time for confluence=20
over New England and Nova Scotia to weaken, giving the shortwave=20
more time to amplify, and allow for closer storm tracks to the=20
coast that bring heavy snow as far west as the I-95 corridor (some=20
GEFS members and some CMCE members). Where the shortwave is=20
stronger but progressive, heavier snowfall occurs but largely=20
closer to the coast and as far west as the NC Piedmont (CMCE=20
members, UK ensembles, split EC/GEFS members). If the shortwave=20
trough is more progressive and cannot separate itself from the=20
larger TPV to the east there is less amplification, it results in=20
a flatter and more positively/tilted shortwave trough, and thus the storm remains largely out at sea (EPS, EC-AIFS ensembles, some GEFS/CMCE
members). It is worth noting that, while the EC-AIFS has largely=20
performed well inside of 5 days much of the winter season, the EC-=20
AIFS and ECMWF did suppress the track of the most recent winter=20
storm too much ~4-5 days out before correcting northward inside of=20
72 hours out.

This setup is highly timing dependent; from the primary shortwave
trough currently east of Hudson Bay, to the interaction/spacing of
the 500mb cyclonic gyres in southeast Canada and south of Iceland
that promote the confluence ahead of the potential storm, to the=20
incoming Pacific shortwaves that track into western Canada and
adjust the strength/position of the western North America ridge.=20
There remain a host of embedded shortwaves that will work together=20
to create a complex storm evolution off the East Coast. Whatever=20
the current model solutions show beyond 72 hours out is unlikely to
be the final product. Expect additional model changes in the=20
coming days. If there is one thing that has increased in confidence
in the past 24 hours, it is the opportunity for coastal flooding=20
and beach erosion along the Mid-Atlantic coast. Please refer to our
"What We know, What We Don't Know" social media post for=20
additional information.

The one thing they do agree on is this upper trough tracks through
the OH Valley Friday afternoon with sufficient PVA and 850-500mb=20
mean layer moisture to support snow from central KY to the southern Appalachians through Friday evening. WPC probabilities do
show increasing chances for at least minor accumulations >2" over
KY and northeast TN, while there are low-chances (10-30%) for
snowfall totals >4" through early Saturday morning in the TN/NC
Smokeys and Blue Ridge of NC. Residents and those traveling to the
Carolinas on north up the East Coast will want to continue=20
following the forecasts from WPC and your local NWS WFO for the=20
latest regarding this potential winter storm.=20


The probability for significant icing is less than 10 percent.


Mullinax





...Winter Storm Key Messages are in effect. Please see current=20
Key Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!54SB-pOI55Au96P5L94fHwqMmZ5LkWpzYAasipw8QCoDB= HpKat7rnUR9CGCuvaNDYBiVEtFlpNZAFxNTxzAKGVc0XKY$=20



$$

=3D =3D =3D
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--- SBBSecho 3.28-Linux
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FOUS11 KWBC 272012
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
312 PM EST Tue Jan 27 2026

Valid 00Z Wed Jan 28 2026 - 00Z Sat Jan 31 2026


...Great Lakes...
Days 1-3...

The seemingly endless cyclonic flow that has kept the LES machine=20
cranking over snow belts of the Great Lakes looks to continue
through the remainder of the work-week. Frigid 850mb temperatures=20
will persist with temperatures around -18 to -24C, which are below
the 10th climatological percentile. According to GLERL, Lake Erie=20
is essentially ice covered, so available moisture will be limited=20
there while Lakes Superior and Ontario remain largely open. W-NWrly
low-level winds will continue through Wednesday before the approach
of a sharp 500mb shortwave pivots through and shifts winds more out
of the N-NNW by Thursday. Northerly flow continues Friday as high
pressure builds in over the Northern Plains. 72-hour WPC
probabilities depict high chances (>70%) for snowfall totals >4"
over the northern tier of the Michigan U.P. and down wind of Lake=20
Ontario to the south of an over the Tug Hill. The area with the=20
best odds of seeing over a foot of snow over the next few days are=20
near the Oswego, NY area where WPC probabilities for over a foot of
snow are in the moderate range of probabilities (40-60%).=20


...Cascades & Olympics...
Days 1-3...

A series of storm systems tracking into the Gulf of Alaska will
direct rounds of moisture and WAA at western WA through the
remainder of the week. Strong upslope flow should support locally
heavy snowfall totals as low as 4,000ft, but most heavy snow will=20
reside in the more remote areas above 5,000ft. Snow levels rise=20
from 4000 to 5000ft over the WA Cascades Wednesday through=20
Thursday. By Friday, snow levels approach 6,000ft by Friday in
western WA. WPC probabilities for >4" is high (>70%) around Stevens
Pass, but lighter accumulations around Snoqualmie are anticipated
at this moment given the higher snow levels.

...Northern & Central Plains...
Days 2-3...

A weak Pacific shortwave trough tracking NW-SE will ride along a
nearby 850mb front to support periods of snow from the northern
High Plains on south in the the central High Plains. Snow is not
expected to be overly heavy, although the Black Hills through
orographic lifting may be able to see snowfall amounts surpass 6".
This is supported in WPC probabilities which show moderate-to-high
chances (50-70%) for >4" of snow in the Black Hills, and low
chances (10-30%) in their peaks for >8". Elsewhere, from eastern MT
on south and east through the Missouri River Valley, most snowfall accumulations are likely to range between 1-3". Some hazardous
travel is possible, especially where roads temperatures are at or
below freezing in wake of the recent extreme cold.


...Southern Appalachians & Mid-Atlantic...
Days 3-3.5...

...Confidence In Impactful Snowfall Increasing For the Southern=20
Appalachians and Southern Mid-Atlantic...

To say there remains a large amount of model spread in the
potential winter storm beyond Day 3 would be an understatement. In
the past 24 hours, ensemble guidance have flipped camps to where
the GEFS are the snowier members, CMCE are more in the middle, and
the EC-EPS are trending less snowy. It is worth noting that AI=20
ensemble membership are not as snowy as the GEFS, but show a little
more snow than the EC-EPS, making this an interesting test in how=20
the AI ensemble membership performs.=20

Regarding the setup-- WPC Cluster Analysis shows this potential=20
winter storm comes down to several factors: 1) strength of the=20
emerging Great Lakes shortwave trough. 2) speed of the shortwave=20
trough. 3) tilt/amplitude of the shortwave trough as it tracks=20
east. 4) Confluence strength near Nova Scotia. They all work=20
together in an intricate dance that makes for difficulties in=20
modeling. A stronger/slower shortwave can buy time for confluence=20
over New England and Nova Scotia to weaken, giving the shortwave=20
more time to amplify, and allow for closer storm tracks to the=20
coast that bring heavy snow as far west as the I-95 corridor (some=20
GEFS members and some CMCE members). Where the shortwave is=20
stronger but progressive, heavier snowfall occurs but largely=20
closer to the coast and as far west as the NC Piedmont (CMCE=20
members, UK ensembles, split EC/GEFS members). If the shortwave=20
trough is more progressive and cannot separate itself from the=20
larger TPV to the east there is less amplification, it results in=20
a flatter and more positively/tilted shortwave trough, and thus the
storm remains largely out at sea (EPS, EC-AIFS ensembles, some=20
GEFS/CMCE members). It is worth noting that, while the EC-AIFS has=20
largely performed well inside of 5 days much of the winter season,=20
the EC- AIFS and ECMWF did suppress the track of the most recent=20
winter storm too much ~4-5 days out before correcting northward=20
inside of 72 hours out.

This setup is highly timing dependent; from the primary shortwave
trough currently east of Hudson Bay, to the interaction/spacing of
the 500mb cyclonic gyres in southeast Canada and south of Iceland
that promote the confluence ahead of the potential storm, to the=20
incoming Pacific shortwaves that track into western Canada and
adjust the strength/position of the western North America ridge.=20
There remain a host of embedded shortwaves that will work together=20
to create a complex storm evolution off the East Coast. Whatever=20
the current model solutions show beyond 72 hours out is unlikely to
be the final product. Expect additional model changes in the=20
coming days. If there is one thing that has increased in confidence
in the past 24 hours, it is the opportunity for coastal flooding=20
and beach erosion along the Mid-Atlantic coast. Please refer to our
"What We know, What We Don't Know" social media post for=20
additional information.

The one thing they do agree on is this upper trough tracks through
the OH Valley Friday afternoon with sufficient PVA and 850-500mb=20
mean layer moisture to support snow from central KY to the southern Appalachians through Friday evening. WPC probabilities do
show increasing chances for at least minor accumulations >2" over
KY and northeast TN, while there are low-chances (10-30%) for
snowfall totals >4" through early Saturday morning in the TN/NC
Smokeys and Blue Ridge of NC. Residents and those traveling to the
Carolinas on north up the East Coast will want to continue=20
following the forecasts from WPC and your local NWS WFO for the=20
latest regarding this potential winter storm.=20


The probability for significant icing is less than 10 percent.


Mullinax






...Winter Storm Key Messages are in effect. Please see current=20
Key Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!6n-iHJKs776ZdQQmter1T3bY9tYWwGaL_csVXzv1NZMbv= Z1KeGyQSUWbB1TKYcgb1-m6K7MWiSPxJKNPHtV9eyKYDFI$=20



$$

=3D =3D =3D
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--- SBBSecho 3.28-Linux
* Origin: Capitol City Online (1:2320/105)

FOUS11 KWBC 280759
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
259 AM EST Wed Jan 28 2026

Valid 12Z Wed Jan 28 2026 - 12Z Sat Jan 31 2026


...Great Lakes...
Days 1-3...

The seemingly endless cyclonic flow that has kept the LES machine=20
cranking over snow belts of the Great Lakes looks to continue
through the remainder of the work-week. Frigid 850mb temperatures=20
will persist with temperatures around -18 to -24C, which are below
the 10th climatological percentile. According to GLERL, Lake Erie=20
is essentially ice covered, so available moisture will be limited=20
there while Lakes Superior and Ontario remain largely open. W-NWrly
low-level winds will continue today before the approach of a sharp
500mb shortwave pivots through and shifts winds more out of the=20
N-NNW by Thursday. Northerly flow continues Friday as high pressure
builds in over the Northern Plains. This northerly flow supports
the most likely area of heavy snow on Day 3 to be down wind of Lake
Michigan, potentially into the Chicago metro. 72-hour WPC=20
probabilities depict high chances (>70%) for snowfall totals >8"=20
over the eastern shores of Lake Superior in the Michigan U.P. and=20
down wind of Lake Ontario to the south of an over the Tug Hill. The
area with the best odds of seeing over a foot of additional snow=20
(most on Day 1) over the next few days are near the Oswego, NY area
where WPC probabilities for over a foot of snow are 10-20%. Day 3
probabilities down wind of Lake Michigan current depict moderate
probabilities 40-50% for at least 4" across the southwest shores of
Lake Michigan.


...Cascades & Olympics...
Days 1-3...

A series of storm systems tracking into the Gulf of Alaska will
direct rounds of moisture and WAA at western WA through the
remainder of the week. Strong upslope flow should support locally
heavy snowfall totals as low as 4,000ft, but most heavy snow will=20
reside in the more remote areas above 5,000ft. Snow levels rise=20
from 4000 to 5000ft over the WA Cascades Wednesday through=20
Thursday. By Friday, snow levels approach 6,000ft by Friday in
western WA. WPC probabilities for >4" is moderate (40-70%) around=20
Stevens Pass, but lighter accumulations around Snoqualmie are=20
anticipated at this moment given the higher snow levels.

...Northern & Central Plains...
Days 2-3...

A weak Pacific shortwave trough tracking NW-SE will ride along a
nearby 850mb front to support periods of snow from the northern
High Plains on south in the the central High Plains. Snow is not
expected to be overly heavy, although the Black Hills through
orographic lifting may be able to see snowfall amounts surpass 6".
This is supported in WPC probabilities which show moderate-to-high
chances (50-70%) for >4" of snow in the Black Hills, and low
chances (10-30%) in their peaks for >8". Elsewhere, from eastern MT
on south and east through the Missouri River Valley, most snowfall accumulations are likely to range between 1-3". Some hazardous
travel is possible, especially where roads temperatures are at or
below freezing in wake of the recent extreme cold.


...Southern Appalachians & Mid-Atlantic...
Days 3...

...Confidence In Impactful Snowfall Increasing For the Southern=20
Appalachians and Southern Mid-Atlantic; Key Messages are linked at
the bottom of the discussion...

To say there remains a large amount of model spread in the
potential winter storm beyond Day 3 would be an understatement. In
the past 36-24 hours, ensemble guidance have flipped camps to=20
where the GEFS are the snowier members, CMCE are more in the=20
middle, and the EC-EPS are less snowy. It is worth noting that AI=20
ensemble membership are not as snowy as the GEFS, but show a little
more snow than the EC-EPS, making this an interesting test in how=20
the AI ensemble membership performs. However, within this overall
"cloud" of uncertainty, guidance is beginning to hone in on higher
chances for impactful snowfall across the Carolinas and southern
Virginia by the end of the Day 3 timeframe.

Regarding the setup-- WPC Cluster Analysis shows this potential=20
winter storm comes down to several factors: 1) strength of the=20
emerging Great Lakes shortwave trough. 2) speed of the shortwave=20
trough. 3) tilt/amplitude of the shortwave trough as it tracks=20
east. 4) Confluence strength near Nova Scotia. They all work=20
together in an intricate dance that makes for difficulties in=20
modeling. A stronger/slower shortwave can buy time for confluence=20
over New England and Nova Scotia to weaken, giving the shortwave=20
more time to amplify, and allow for closer storm tracks to the=20
coast that bring heavy snow as far west as the I-95 corridor (some=20
GEFS members and some CMCE members). Where the shortwave is=20
stronger but progressive, heavier snowfall occurs but largely=20
closer to the coast and as far west as the NC Piedmont (CMCE=20
members, UK ensembles, split EC/GEFS members). If the shortwave=20
trough is more progressive and cannot separate itself from the=20
larger TPV to the east there is less amplification, it results in=20
a flatter and more positively/tilted shortwave trough, and thus the
storm remains largely out at sea (EPS, EC-AIFS ensembles, some=20
GEFS/CMCE members). It is worth noting that, while the EC-AIFS has=20
largely performed well inside of 5 days much of the winter season,=20
the EC- AIFS and ECMWF did suppress the track of the most recent=20
winter storm too much ~4-5 days out before correcting northward=20
inside of 72 hours out.

In terms of storm analogs, this upper level setup and TPV=20
interaction does not appear like a common scenario to get a deep=20
upper low rapidly deepening near the Southeast/Mid- Atlantic. Most=20
analog matches seem to get towards the closed upper low in=20
different ways or suppress the system altogether leaving little in=20
terms of precipitation. However, the 12z Tuesday CIPS Analogs
(GFS-based) highlighted the significant winter storm of March 1980
as an interesting top match. This storm produced very heavy=20
snowfall across VA and eastern NC and can simply show the ceiling=20
this type of setup can have. Like what was previously mentioned,=20
other limited analogs are suppressed and show the very low floor=20
that is still possible. All ensemble systems GEFS/CMCE/EPS/EC-
AIFS/AIGEFS show this large spread as well.

Back to the current forecast. This setup is highly timing=20
dependent; from the primary shortwave trough currently east of=20
Hudson Bay, to the interaction/spacing of the 500mb cyclonic gyres=20
in southeast Canada and south of Iceland that promote the=20
confluence ahead of the potential storm, to the incoming Pacific=20
shortwaves that track into western Canada and adjust the=20
strength/position of the western North America ridge. There remain=20
a host of embedded shortwaves that will work together to create a=20
complex storm evolution off the East Coast. Whatever the current=20
model solutions show beyond 72 hours out is unlikely to be the=20
final product. Expect additional model changes in the coming days.=20
If there is an additional aspect to this storm that has increased=20
in confidence in the past 24 hours, it is the opportunity for=20
coastal flooding and beach erosion along the Mid-Atlantic coast.

The one thing they do agree on is this upper trough tracks through
the OH Valley Friday afternoon with sufficient PVA and 850-500mb=20
mean layer moisture to support snow from central KY to the southern Appalachians through Friday night. Then, the closing off of a 850mb
low seems plausible across the southern Appalachians Saturday=20
morning, which should help increase lift into the Carolina=20
Piedmont. WPC probabilities do show increasing chances for at least
minor accumulations >4" over eastern KY and northeast TN, while=20
there are low- chances (10-30%) for snowfall totals >4" through=20
early Saturday morning in the TN/NC Smokeys and Blue Ridge of NC.=20 Probabilities then begin to increase to 30-50% across central NC by
12z Saturday. Most snowfall associated with this system is=20
expected to occur after 12z Saturday, so be sure to check back for=20
the latest forecast as it enters the short range over the next few=20
days. Residents and those traveling to the Carolinas on north up=20
the East Coast will want to continue following the forecasts from=20
WPC and your local NWS WFO for the latest regarding this potential=20
winter storm.



The probability for significant icing is less than 10 percent.


Snell/Mullinax





...Extreme Cold (1) & Winter Storm (2) Key Messages are in effect.
Please see current Key Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!77Xu4C4_ejyNPuXJ8gEnnObVKlTXBwG2suWpfLuKOVzPG= BINbP5K5P9TIQ5cCqP2wLS3M1N8_NCpSzZOgD1PInZ4pUQ$=20

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_2.png__;!!DZ3fjg!77Xu4C4_ejyNPuXJ8gEnnObVKlTXBwG2suWpfLuKOVzPG= BINbP5K5P9TIQ5cCqP2wLS3M1N8_NCpSzZOgD1PtfsLqMU$=20



$$

=3D =3D =3D
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--- SBBSecho 3.28-Linux
* Origin: Capitol City Online (1:2320/105)

FOUS11 KWBC 280807
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
307 AM EST Wed Jan 28 2026

Valid 12Z Wed Jan 28 2026 - 12Z Sat Jan 31 2026


...Great Lakes...
Days 1-3...

The seemingly endless cyclonic flow that has kept the LES machine=20
cranking over snow belts of the Great Lakes looks to continue
through the remainder of the work-week. Frigid 850mb temperatures=20
will persist with temperatures around -18 to -24C, which are below
the 10th climatological percentile. According to GLERL, Lake Erie=20
is essentially ice covered, so available moisture will be limited=20
there while Lakes Superior and Ontario remain largely open. W-NWrly
low-level winds will continue today before the approach of a sharp
500mb shortwave pivots through and shifts winds more out of the=20
N-NNW by Thursday. Northerly flow continues Friday as high pressure
builds in over the Northern Plains. This northerly flow supports
the most likely area of heavy snow on Day 3 to be down wind of Lake
Michigan, potentially into the Chicago metro. 72-hour WPC=20
probabilities depict high chances (>70%) for snowfall totals >8"=20
over the eastern shores of Lake Superior in the Michigan U.P. and=20
down wind of Lake Ontario to the south of an over the Tug Hill. The
area with the best odds of seeing over a foot of additional snow=20
(most on Day 1) over the next few days are near the Oswego, NY area
where WPC probabilities for over a foot of snow are 10-20%. Day 3
probabilities down wind of Lake Michigan current depict moderate
probabilities 40-50% for at least 4" across the southwest shores of
Lake Michigan.


...Cascades & Olympics...
Days 1-3...

A series of storm systems tracking into the Gulf of Alaska will
direct rounds of moisture and WAA at western WA through the
remainder of the week. Strong upslope flow should support locally
heavy snowfall totals as low as 4,000ft, but most heavy snow will=20
reside in the more remote areas above 5,000ft. Snow levels rise=20
from 4000 to 5000ft over the WA Cascades Wednesday through=20
Thursday. By Friday, snow levels approach 6,000ft by Friday in
western WA. WPC probabilities for >4" is moderate (40-70%) around=20
Stevens Pass, but lighter accumulations around Snoqualmie are=20
anticipated at this moment given the higher snow levels.

...Northern & Central Plains...
Days 2-3...

A weak Pacific shortwave trough tracking NW-SE will ride along a
nearby 850mb front to support periods of snow from the northern
High Plains on south in the the central High Plains. Snow is not
expected to be overly heavy, although the Black Hills through
orographic lifting may be able to see snowfall amounts surpass 6".
This is supported in WPC probabilities which show moderate-to-high
chances (50-70%) for >4" of snow in the Black Hills, and low
chances (10-30%) in their peaks for >8". Elsewhere, from eastern MT
on south and east through the Missouri River Valley, most snowfall accumulations are likely to range between 1-3". Some hazardous
travel is possible, especially where roads temperatures are at or
below freezing in wake of the recent extreme cold.


...Southern Appalachians & Mid-Atlantic...
Days 3...

...Confidence In Impactful Snowfall Increasing For the Southern=20
Appalachians and Southern Mid-Atlantic; Key Messages are linked at
the bottom of the discussion...

To say there remains a large amount of model spread in the
potential winter storm beyond Day 3 would be an understatement. In
the past 36-24 hours, ensemble guidance have flipped camps to=20
where the GEFS are the snowier members, CMCE are more in the=20
middle, and the EC-EPS are less snowy. It is worth noting that AI=20
ensemble membership are not as snowy as the GEFS, but show a little
more snow than the EC-EPS, making this an interesting test in how=20
the AI ensemble membership performs. However, within this overall
"cloud" of uncertainty, guidance is beginning to hone in on higher
chances for impactful snowfall across the Carolinas and southern
Virginia by the end of the Day 3 timeframe.

Regarding the setup-- WPC Cluster Analysis shows this potential=20
winter storm comes down to several factors: 1) strength of the=20
emerging Great Lakes shortwave trough. 2) speed of the shortwave=20
trough. 3) tilt/amplitude of the shortwave trough as it tracks=20
east. 4) Confluence strength near Nova Scotia. They all work=20
together in an intricate dance that makes for difficulties in=20
modeling. A stronger/slower shortwave can buy time for confluence=20
over New England and Nova Scotia to weaken, giving the shortwave=20
more time to amplify, and allow for closer storm tracks to the=20
coast that bring heavy snow as far west as the I-95 corridor (some=20
GEFS members and some CMCE members). Where the shortwave is=20
stronger but progressive, heavier snowfall occurs but largely=20
closer to the coast and as far west as the NC Piedmont (CMCE=20
members, UK ensembles, split EC/GEFS members). If the shortwave=20
trough is more progressive and cannot separate itself from the=20
larger TPV to the east there is less amplification, it results in=20
a flatter and more positively/tilted shortwave trough, and thus the
storm remains largely out at sea (EPS, EC-AIFS ensembles, some=20
GEFS/CMCE members). It is worth noting that, while the EC-AIFS has=20
largely performed well inside of 5 days much of the winter season,=20
the EC- AIFS and ECMWF did suppress the track of the most recent=20
winter storm too much ~4-5 days out before correcting northward=20
inside of 72 hours out.

In terms of storm analogs, this upper level setup and TPV=20
interaction does not appear like a common scenario to get a deep=20
upper low rapidly strengthening near the Southeast/Mid- Atlantic.=20
Most analog matches seem to get towards the closed upper low in=20
different ways or suppress the system altogether leaving little in=20
terms of precipitation. However, the 12z Tuesday CIPS Analogs (GFS-
based) highlighted the significant winter storm of March 1980 as=20
an interesting top match. This storm produced very heavy snowfall=20
across VA and eastern NC and can simply show the ceiling this type=20
of setup can have. Like what was previously mentioned, other=20
limited analogs are suppressed and show the very low floor that is=20
still possible. All ensemble systems GEFS/CMCE/EPS/EC- AIFS/AIGEFS=20
show this large spread as well.

Back to the current forecast. This setup is highly timing=20
dependent; from the primary shortwave trough currently east of=20
Hudson Bay, to the interaction/spacing of the 500mb cyclonic gyres=20
in southeast Canada and south of Iceland that promote the=20
confluence ahead of the potential storm, to the incoming Pacific=20
shortwaves that track into western Canada and adjust the=20
strength/position of the western North America ridge. There remain=20
a host of embedded shortwaves that will work together to create a=20
complex storm evolution off the East Coast. Whatever the current=20
model solutions show beyond 72 hours out is unlikely to be the=20
final product. Expect additional model changes in the coming days.=20
If there is an additional aspect to this storm that has increased=20
in confidence in the past 24 hours, it is the opportunity for=20
coastal flooding and beach erosion along the Mid-Atlantic coast.

The one thing they do agree on is this upper trough tracks through
the OH Valley Friday afternoon with sufficient PVA and 850-500mb=20
mean layer moisture to support snow from central KY to the southern Appalachians through Friday night. Then, the closing off of a 850mb
low seems plausible across the southern Appalachians Saturday=20
morning, which should help increase lift into the Carolina=20
Piedmont. WPC probabilities do show increasing chances for at least
minor accumulations >4" over eastern KY and northeast TN, while=20
there are low- chances (10-30%) for snowfall totals >4" through=20
early Saturday morning in the TN/NC Smokeys and Blue Ridge of NC.=20 Probabilities then begin to increase to 30-50% across central NC by
12z Saturday. Most snowfall associated with this system is=20
expected to occur after 12z Saturday, so be sure to check back for=20
the latest forecast as it enters the short range over the next few=20
days. Residents and those traveling to the Carolinas on north up=20
the East Coast will want to continue following the forecasts from=20
WPC and your local NWS WFO for the latest regarding this potential=20
winter storm.



The probability for significant icing is less than 10 percent.


Snell/Mullinax





...Extreme Cold (1) & Winter Storm (2) Key Messages are in effect.
Please see current Key Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!8TANDUoTZL_uMahppCEn7lOgTUVSMGtUDbz_RXsEfHhME= ATsMx_veotJcy8MV2KCSOFvGpr4l7xjG6CeUg9vKvyvDL8$=20

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_2.png__;!!DZ3fjg!8TANDUoTZL_uMahppCEn7lOgTUVSMGtUDbz_RXsEfHhME= ATsMx_veotJcy8MV2KCSOFvGpr4l7xjG6CeUg9vTm6w4sc$=20



$$

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FOUS11 KWBC 281947
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
247 PM EST Wed Jan 28 2026

Valid 00Z Thu Jan 29 2026 - 00Z Sun Feb 01 2026


...Great Lakes...
Days 1-3...

The seemingly endless cyclonic flow that has kept the LES machine=20
cranking over snow belts of the Great Lakes looks to continue
through the remainder of the work-week. Frigid 850mb temperatures=20
will persist with temperatures around -18 to -24C, which are below
the 10th climatological percentile. According to GLERL, Lake Erie=20
is effectively ice covered, so available moisture will be limited=20
there while Lakes Superior and Ontario remain largely open. W-NWrly
low-level winds will continue today before the approach of a sharp
500mb shortwave passes through and shifts winds more out of the=20
north by late Thursday. Northerly flow continues Friday with=20
shifting NNE flow possible into Saturday, which could place the=20
Chicagoland area under the presence of a Lake Michigan single-=20
banded LES streamer late Friday into Saturday. 72-hour WPC=20
probabilities depict high chances (>70%) for snowfall totals >8"=20
over the eastern shores of Lake Superior in the Michigan U.P. and=20
down wind of Lake Ontario to the south of an over the Tug Hill. The
area with the best odds of seeing over a foot of additional snow=20
(most on Day 1) over the next few days are near the Oswego, NY area
where WPC probabilities for over a foot of snow are 10-20%. Day 3=20 probabilities down wind of Lake Michigan current depict moderate-=20
to-high chances (40-70%) for at least 4" along the southern shores
of Lake Michigan.


...Cascades & Olympics...
Days 1-3...

A series of storm systems tracking into the Gulf of Alaska will
direct rounds of moisture and WAA at western WA through the
remainder of the week. Strong upslope flow should support locally
heavy snowfall totals as low as 4,000ft, but most heavy snow will=20
reside in the more remote areas above 5,000ft. Snow levels rise=20
from 4000 to 5000ft over the WA Cascades Wednesday through=20
Thursday. By Friday, snow levels approach 6,000ft by Friday in
western WA. WPC probabilities for >4" is moderate (40-60%) around=20
Stevens Pass, but lighter accumulations around Snoqualmie are=20
anticipated at this moment given the higher snow levels.

...Northern & Central Plains...
Days 1-3...

A weak Pacific shortwave trough tracking NW-SE will ride along a
nearby 850mb front to support periods of snow from the northern
High Plains on south in the the central High Plains. Guidance is
even keying in on an area of 700mb FGEN over the Black Hills on
south into the Nebraska Sand Hills that could support moderate snow
bands Friday morning. Snow is not expected to be overly heavy,=20
although the Black Hills through orographic lifting and some=20
localized banding may be able to see snowfall amounts surpass 6".=20
This is supported in WPC probabilities which show moderate-to-high=20
chances (50-70%) for >4" of snow in the Black Hills, and low-to-=20
moderate chances (20-50%) in their peaks for >8". Elsewhere, from=20
eastern MT on south and east through the Missouri River Valley,=20
most snowfall accumulations are likely to range between 1-3". Even=20
some localized instances of freezing rain in the northern High=20
Plains on late Friday into Saturday given the favorable overrunning
from WAA at low-mid levels and sub-freezing surface temps. Some=20
hazardous travel is possible, especially where roads temperatures=20
are at or below freezing in wake of the recent extreme cold.


...Southern Appalachians & Mid-Atlantic...
Days 2.5-3.5...

...Confidence growing for a major winter storm & heavy snowfall=20
across the southern Mid-Atlantic...

WPC cluster analysis continues to show the primary driving factors
in the development of this impending winter storm are the
strength/speed/tilt of the approaching shortwave trough in the
Great Lakes and the spacing between the trough and the TPV over
southeast Canada. The meteorology is supportive of a significant
winter storm from the southern Appalachians and Carolinas on north
and east through the VA Tidewater. Just about all ensemble=20
guidance now show the shortwave trough over the OH Valley Friday=20
evening deepening into a powerful and highly anomalous closed low=20
that tracks into the southern Appalachians Saturday evening. By the
end of this forecast period (00Z Sun) the ECMWF 500mb heights are=20 approaching record low levels over the FL Panhandle for late Jan-=20
early Feb. As the 500mb low approaches, exceptional PVA and WAA=20
over the Mid-Atlantic coast will spawn low pressure along the=20
strengthening coastal front. This aligns well across the 12Z GFS=20
and 06Z ECMWF which show increasing 700mb Q-vector convergence near
the NC Outer Banks that fosters healthy mid-level ascent. This=20
aligns favorably beneath the diffluent left-exit region of a=20

100kt 500mb jet streak located a the base of the closed 500mb low.

As the 700mb low tracks towards the Cape Fear region Saturday=20
night, the axis of heaviest snowfall will reside on the 700mb low's
northern and western flank.

Where guidance still disagrees is the progression of the storm and
its proximity to the coast. The tilt of the 500mb trough and closed
low plays a key role in this, as it maximizes vertical ascent and=20
draws moisture farther north if the system takes on a negative=20
tilt. The EC-AIFS ensemble mean has been gradually decreasing QPF=20
largely because the negative tilt takes longer to occur and there=20
is less time for the developing 850mb low to tap into moisture off
the Gulf Stream. Most guidance holds off on a negative until=20
Sunday, which is why there is a "gap" in the snowfall from northern
VA on up I-95 to the NYC metro area, but heavy snow becomes=20
possible over southeast New England by Sunday thanks to the region=20
sticking out eastward into the Atlantic. Note the 12Z GEFS, 06Z=20
EPS, and 12Z EC-AIFS ensembles are still showing changes in its=20
mean inside of 72 hours, so exact amounts and the expanse of the=20
snow shield are still likely to change. In addition, unlike the=20
last winter storm, wind will have a more profound impact up and=20
down the Eastern Seaboard. The 00Z ECMWF EFI shows wind speeds that
are topping 0.8 from the MA Capes on south along the NC Coast.=20
These anomalous winds also align with climatologically significant=20
snowfall potential along the coasts, indicating the concern for=20
blizzard conditions in affected coastal areas.=20

CIPS Analogs (GFS-based) continue to suggest this storm's=20
potential ceiling could be exceptional, particularly in the=20
Carolinas. CIPS is keying in on several past major winter storms=20
that featured similar 300mb & 500mb evolutions to what the GFS is=20
showing, just 100-200 miles farther south and east from where those
events unfolded. While the CIPS analogs are analyzing the GFS, the
differences in the GFS versus the ECMWF are not all that different
when it comes to the meteorology involved: powerful closed upper=20
low, healthy upper-level divergence over a strengthening coastal=20
front, and tapping into Atlantic moisture revolving around the=20
closed 700mb low. In summary-- ensembles are beginning to identify
the floor of this winter storm (disruptive winter storm in the=20
southern Mid-Atlantic) but based on some of the analogs, there is a
potentially more significant-ceiling that could be achieved in the
Carolinas should guidance consolidate on a slower and more intense
winter storm. Given it is 72 hours out, there remains some caution
when it comes to expected snowfall totals.

WPC probabilities through Saturday night currently show moderate-
to-high chances (50-80%) for snowfall totals >4" from the NC=20
Piedmont on east to eastern NC and southeast VA. It is worth noting
some higher end solutions are present with low-to-moderate chances
(30-50%) for snowfall totals >8" over central NC through 06Z Sunday.
The Probabilistic Winter Storm Severity Index (WSSI-P) is=20
depicting >50% chances for Moderate Impacts from the SC/GA border=20
on north and east to lower DelMarVa Peninsula. The Major Impacts=20
are >50% in the eastern Charlotte metro, the NC Piedmont right=20
along NC's I-95 corridor, and into southeast VA. These elevated
WSSI-P Major probabilities highlight the concern for a highly=20
impactful winter storm late Saturday and into Sunday for the=20
southern Mid-Atlantic with more disruptions to travel and=20
infrastructure anticipated. Residents and those traveling to the=20
Carolinas on north up the East Coast will want to continue=20
following the forecasts from WPC and your local NWS WFO for the=20
latest regarding this potential winter storm.


The probability for significant icing is less than 10 percent.


Mullinax




...Winter Storm Key Messages are in effect. Please see current=20
Key Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!5Cj4msK-dv0Kb7_AGDSgu7ZDdEOXNYFYPw2QvpYtmFd6N= CNtmp24XMTtrscfs6fvs4sGCn1UXXix-0GDZBAeT4q-EBM$=20

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_2.png__;!!DZ3fjg!5Cj4msK-dv0Kb7_AGDSgu7ZDdEOXNYFYPw2QvpYtmFd6N= CNtmp24XMTtrscfs6fvs4sGCn1UXXix-0GDZBAeMWJe7mA$=20



$$

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FOUS11 KWBC 290746
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
246 AM EST Thu Jan 29 2026

Valid 12Z Thu Jan 29 2026 - 12Z Sun Feb 01 2026


...Great Lakes...
Days 1-2...

Continued cyclonic flow will continue to favor lake effect snow=20
across the Great Lakes for another couple of days. Frigid 850mb=20
temperatures will persist with temperatures around -18 to=20
-24C, which are below the 10th climatological percentile. WNW flow
will turn more northerly (or NNE) as the sharp 500mb shortwave
passes through later today. On Friday, northerly flow continues
Friday with NNE flow possible into Chicagoland carrying a band
into the region overnight into Saturday. Most snow winds downs
late Saturday into early Sunday with a surface high overhead.
Single band off Lake Ontario will weaken later today but persist
through Friday.

For days 1-2, WPC probabilities for at least 6 inches of snow are

50% over parts of the Michigan U.P. and downwind of Lake Ontario=20

near Oswego, where over 10 inches is possible. Over Chicago, WPC=20 probabilities for at least 4 inches are not quite 30% but some CAM=20
guidance shows a farther westward push out of NW Indiana than=20
others.=20


...Cascades & Olympics...
Days 1-2...

A series of storm systems tracking into the Gulf of Alaska will=20
direct rounds of moisture and WAA at western WA through the=20
remainder of the week. Strong upslope flow should support locally=20
heavy snowfall totals above 5,000ft. Snow levels approach=20
6,000-6,500ft by Friday into Saturday in western WA as=20
precipitation ends.=20


...Northern & Central Plains...
Days 1-3...

A weak Pacific shortwave trough tracking NW-SE will ride along a=20
nearby 850mb front to support periods of snow from the northern=20
High Plains on south in the the central High Plains. Guidance is=20
even keying in on an area of 700mb FGEN over the Black Hills on=20
south into the Nebraska Sand Hills that could support moderate snow
bands Friday morning. Snow is not expected to be overly heavy,=20
although the Black Hills through orographic lifting and some=20
localized banding may be able to see snowfall amounts surpass 6".=20
This is supported in WPC probabilities which show 60-80%=20
probabilities for >4" of snow in the Black Hills, and low-to-=20
moderate chances (20-50%) in their peaks for >8". Elsewhere, from=20
eastern MT on south and east through the Missouri River Valley,=20
most snowfall accumulations are likely to range between 1-3". Even=20
some localized instances of freezing rain in the northern High=20
Plains on late Friday into Saturday given the favorable overrunning
from WAA at low-mid levels and sub-freezing surface temps. Some=20
hazardous travel is possible, especially where roads temperatures=20
are likely below freezing in the wake of the recent extreme cold.


...Southern Appalachians & Mid-Atlantic...
Days 2-3...

...Confidence growing for a major winter storm & heavy snowfall=20
across the southern Mid-Atlantic...

Models continue to point to an anomalous and impactful event for=20
the southern Appalachians and especially southern Mid-Atlantic=20
states this weekend, aided by record cold into the=20
Southeast/Florida. Though the various models/ensembles have wavered
in their evolution and track of the system, nearly all show a=20
powerful ocean storm that will affect the southern Mid-Atlantic as=20 cyclogenesis ensues.=20

As a very deep 500mb low approaches the region, exceptional PVA=20
and WAA over the Mid-Atlantic coast will spawn low pressure along=20
the strengthening coastal front. Increasing 700mb Q-vector=20
convergence near the NC Outer Banks will foster healthy mid-level=20
ascent beneath the diffluent left-exit region of a >100kt 500mb jet
streak located at the base of the closed 500mb low. As the 700mb=20
low tracks towards the Cape Fear region Saturday night, the axis of
heaviest snowfall will reside on the 700mb low's northern and=20
western flank while surface low pressure explosively deepens into=20
the 970s mb by Sunday morning. Snow will likely fall heavily at=20
times over eastern NC late Saturday into early Sunday west of the=20
surface low as the mid-level upper low eventually catches up. In=20
addition, winds will increase which will create blowing and=20
drifting snow with possible blizzard conditions. Snow will also=20
expand northeastward up along the Mid- Atlantic coast into Long=20
Island and southern/southeastern New England but with a lot of=20
uncertainty in the expanse of the precipitation shield.

Through 12Z Sunday, WPC probabilities for at least 8 inches of=20
snow are >50% over the southern Appalachians, much of central to=20
eastern NC, as well as southern VA and northeastern SC. Within this
region, WPC probabilities for at least 12 inches of snow are >40%=20
over eastern NC. The footprint of impactful snowfall (>2" to the=20
south) extends into northeastern/eastern GA, through much of SC=20
(except for the Lowcountry where ptypes/thermals are more=20
uncertain), and as far north into the DelMarVa and southeastern NJ.


The Probabilistic Winter Storm Severity Index (WSSI-P) shows >50%=20
chances for Major impacts from the NC/SC border to southeastern VA.
These elevated WSSI-P Major probabilities indicate an unusual/rare
event is increasingly likely.=20


The probability for significant icing is less than 10 percent.


Fracasso/Mullinax


...Winter Storm Key Messages are in effect. Please see current Key
Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!4CUOSQKzFnNbuP0ngRlzupRluDzSlOf6XOxWtVIaMamPu= jK5SigKJj5NkEGuj9rswLkOdYSJyPEWhVxQJ46-zwVAXj8$=20

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_2.png__;!!DZ3fjg!4CUOSQKzFnNbuP0ngRlzupRluDzSlOf6XOxWtVIaMamPu= jK5SigKJj5NkEGuj9rswLkOdYSJyPEWhVxQJ46-crIXiPo$=20



$$

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FOUS11 KWBC 292015
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
315 PM EST Thu Jan 29 2026

Valid 00Z Fri Jan 30 2026 - 00Z Mon Feb 02 2026


...Southern Appalachians, Mid-Atlantic, & Southern New England...=20
Days 1-3...

...A major winter storm is expected to produce heavy snowfall=20
across the southern Mid-Atlantic, blizzard conditions along the=20
Mid- Atlantic coasts, & potentially heavy snow in southern New=20
England...

Meteorological Overview...

An arctic air-mass anchored over the eastern U.S. will set the
stage for an amplifying shortwave trough over the OH Valley to
produce a major winter storm over the southern Appalachians and=20
southern Mid-Atlantic beginning Friday afternoon and continuing
into the weekend. Snow will begin as early as Friday morning=20
across the TN Valley and east to the southern/central Appalachians=20
due to low-level WAA, increasing PVA aloft, plus upslope=20
enhancement into the Appalachians. As the upper trough sharpens=20
over near the OH/MS Confluence, a robust >100kt 500mb jet streak=20
will place its divergent left-exit region over the southern Mid-=20
Atlantic and snow will envelop much of the Appalachians and=20
Piedmont of the Southeast come early Saturday morning.=20

By 12Z Saturday, most guidance is in agreement that the 500mb
shortwave takes on a more neutral tilt (oriented N-S) over the TN
Valley and becomes a closed low over GA. PVA becomes maximized=20
over the Southeast while a surface low spawns along a coastal=20
front east of the Carolinas. As the 850mb low deepens over northern
GA and heads east into SC, easterly 850mb theta-e advection will=20
direct low-level moisture around the 850mb low and support a band=20
of moderate-to-heavy snow from northern GA to central SC. Farther=20
north, the same tongue of 850mb theta-e is funneling along the=20
850mb front to the north of the 850mb low track from northern SC=20
on east through the heart of NC. This is where the deformation zone
is likely to form, pivoting over central NC and northern SC with=20
1-2"/hr snowfall rates likely. This band of heavy snow is likely to
ensue farther east into southeast VA, where 700mb FGEN is more=20
ideally placed to support strong vertical velocities within a fully
saturated DGZ. Similar to NC, look for intense bands of heavy snow
over southeast VA to form late Saturday afternoon and persist into
Saturday night. These bands of heavy snow in eastern NC and=20
southeast VA depict 700-500mb lapse rates >6.5C/km Saturday=20
afternoon and evening. It is here where not only are 2"/hr snowfall
rates achievable, but so is the likelihood for thundersnow. The
intense vertical velocities in eastern NC and southeast VA may
result in some subsidence in north-central NC and south-central VA.
Snowfall is still likely to reach warning criteria, but these
regions are potentially susceptible to lesser snowfall amounts as
they are caught between the influence of the strong upper-low to
the south, and the strengthening coastal low.

Speaking of the coastal low, along the coast VA/NC/SC coasts, not=20
only will the deformation zone of heavy snow pivot through, but the
explosive deepening of the storm east of Cape Hatteras will=20
support strong to potentially damaging wind gusts. Latest ECMWF=20
shows low pressure south of Hatteras is around 1007mb at 12Z=20
Saturday, then by 12Z Sunday is 972mb east of Hatteras, indicative=20
of rapid intensification. With strong high pressure to the west, a=20
strong isallobaric flow will develop in response, creating wind=20
gusts along the DelMarVa coast on south through the Outer Banks=20
that could approach hurricane-force at times. These coastal areas=20
overlap with the ECMWF EFI in >0.8 values for both snow and wind,=20
making these areas most susceptible to blizzard conditions. Not to=20
be ignored either, strong wind gusts atop the Smokeys and Blue=20
Ridge are likely to top 60 mph as well, resulting in possible=20
blizzard conditions in those higher elevations of the southern=20
Appalachians. Power outages are likely in some parts of the
southern Mid-Atlantic, particularly areas at risk for those
hurricane-force wind gusts along the VA/NC coast.

While there is still some uncertainty in storm track, most guidance
(including AIFS ensembles) have continued to trend lower in
snowfall amounts from northern VA on north and east along I-95 to=20
the Tri-state area. There remains a high degree of uncertainty over
southeast MA where the differences in the EPS-AIFS 75th and 25th=20
percentile snowfall outcomes south of Boston still are quite=20
striking. The locations that should still contend with periods of=20
snow are Martha's Vineyard and Nantucket given their closer=20
proximity to the snow shield.=20

Snowfall & Impacts...

WPC probabilities for the duration of the event show moderate-to-
high chances (50-80%) for snowfall totals >8" in the Blue
Ridge/Smokeys, west-central NC on east through northern SC,
southern NC, and along the Tidewater regions of VA/NC. It is
southeast VA, eastern NC, and southern NC that feature the highest
odds for snowfall totals >12" at 40-60%. Wilmington, NC has at
least a 50% chance of receiving >12" of snow. For context, dating=20
back to 1870, Wilmington, NC has only observed 3 instances where=20

12" of snowfall occurred: Feb 1896, Feb 1973, and Dec 1989.=20

The snowfall likely to occur across the Carolinas has a good=20
chance to be not just significant but historic and highly=20
disruptive, not just during the event, but for days after it is=20
long gone. WSSI shows an expansive area of Major Impacts=20
(considerable disruptions to daily life; dangerous to impossible=20
travel, widespread closures, disruptions to infrastructure) from=20
central SC (including Columbia, SC) through the eastern two-thirds=20
of NC (Charlotte/Raleigh- Durham). The WSSI-P shows low-to-
moderate chances (20-50%) for Extreme Impacts (per the WSSI=20
legend: extremely dangerous conditions, life saving actions may be
needed) in southern NC, including the I-95 corridor from=20
Fayetteville, NC to Florence, SC. Along the coast, WSSI shows Major
to locally Extreme conditions along VA Beach on south into the=20
northern OBX and along the north and east-facing shores facing the
Pamlico and Albemarle sounds, largely due the blizzard potential=20
and heavy snow. This speaks to the severity of this major winter=20
storm in the Carolinas. Lastly, with frigid temperatures in the=20
storm's wake on Sunday and lasting into Tuesday, the snow will not=20
melt much following the conclusion of the storm. Any melting that=20
occurs thanks to daytime heating is likely to cause refreezing on=20
untreated roads and surfaces. Residents in the Carolinas should=20
finish preparations as soon as possible, as road conditions will be
treacherous Saturday and into the first half of next week.

Elsewhere, travel disruptions are possible as far south and west as
the Atlanta metro area where the WSSI (as of this discussion's
issuance) shows Minor Impacts. Look for measurable snow to cause
hazardous travel as far west as the TN Valley and as far south as
Savannah where snowfall accumulations up to 1" is possible.
Moderate Impacts (hazardous travel and some infrastructure
impacts) are also forecast in Charleston, SC in the Smokeys/Blue=20
Ridge of western NC/TN, and as far north as the southern Richmond,=20
VA suburbs. Impacts are still unclear in southeast MA, but expect=20
blowing snow to cause reduced visibilities in the southeast MA=20
islands.=20


...Great Lakes...
Days 1-2...

Cyclonic flow will continue to favor lake effect snow across the=20
Great Lakes into the first half of the weekend. Frigid 850mb=20
temperatures will persist with temperatures around -18 to -24C,=20
which are below the 10th climatological percentile. WNW flow will=20
turn more northerly (even NNE for a time) as the sharp 500mb=20
shortwave passes over the Great Lakes tonight. On Friday, northerly
flow continues Friday with NNE flow possible into Chicagoland=20
carrying a LES band into the region overnight into Saturday.=20

Latest guidance has favored the heavier snow over far northwest=20
IN, although localized totals approaching 4" along the Lake Michigan
shores in Chicago are possible. Most snowfall winds downs late=20
Saturday into early Sunday as surface high pressure builds in overhead.
Single band off Lake Ontario will weaken starting this afternoon=20
but persist through Friday. For days 1-2, WPC probabilities for at=20
least 4 inches of snow are >50% over parts of the Michigan U.P. and
downwind of Lake Ontario near Oswego, where additional snowfall up
to 8" are possible.

...Northern Great Plains & Upper Midwest...
Days 1-3...

Two rounds of snow are expected; one this evening and into Friday
morning, then the other starting late Friday night and continuing
into the weekend. Weak 850-700mb WAA and FGEN will support light
snow over the western Dakotas and into the Nebraska Sand Hills
tonight and Friday AM. Snowfall totals are likely to range between
1-3" in these areas by the time snow concludes late Friday=20
morning, with the Black Hills sporting low chances (10-30%) for=20
snowfall total over 4". By Friday night, a Pacific shortwave trough
escorts Pacific moisture eastward into the Northern Plains=20
Saturday morning, then into the Upper Midwest Saturday evening into
Sunday. Patches of freezing rain in the northern High Plains on=20
late Friday into Saturday are expected given the favorable=20
overrunning from WAA at low-mid levels and sub-freezing surface=20
temps. Farther east, snow is the more likely precip type from the=20
Red River of the North on south to the Missouri Valley, then east=20
to the Mississippi river and MN Arrowhead. Snow totals are forecast
to range between 1-3" in these areas late Saturday into Sunday.=20
Some hazardous travel is possible, especially where roads=20
temperatures are likely below freezing in the wake of the recent=20
extreme cold.


Mullinax



...Winter Storm Key Messages are in effect. Please see current=20
Key Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!9uwfHTIrXu4nB5pX8IiYt7LWwCT8oOZLhh6Q6IBpUX5Qs= 3ag7Wrua_Ul_oXoc_41EI5uC8IA5fYogem_z21P6LZ1O9o$=20

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_2.png__;!!DZ3fjg!9uwfHTIrXu4nB5pX8IiYt7LWwCT8oOZLhh6Q6IBpUX5Qs= 3ag7Wrua_Ul_oXoc_41EI5uC8IA5fYogem_z21PLNrxWmE$=20



$$

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FOUS11 KWBC 300739
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
239 AM EST Fri Jan 30 2026

Valid 12Z Fri Jan 30 2026 - 12Z Mon Feb 02 2026


...Southern Appalachians, Mid-Atlantic, & Southern New England...=20
Days 1-3...

...A major winter storm is expected to produce heavy snowfall and=20
blizzard conditions across the southern Mid-Atlantic...

Meteorological Overview...

An arctic air mass anchored over the eastern U.S. will set the=20
stage for an amplifying shortwave trough over the OH Valley to=20
produce a major winter storm over the southern Appalachians and=20
southern Mid-Atlantic beginning later this afternoon and continuing
into the weekend. Snow over the TN Valley this morning will move=20
into the southern/central Appalachians this afternoon due to low-
level WAA, increasing PVA aloft, and upslope enhancement. As the=20
upper trough sharpens over/near the OH/MS Confluence, a robust=20

100kt 500mb jet streak will place its divergent left-exit region=20

over the southern Mid-Atlantic and snow will envelop much of the=20 Appalachians and Piedmont of the Southeast early Saturday morning.=20

On Saturday, the 500mb shortwave will take on a N-S neutral tilt=20
over the TN Valley and close off as it enters NW GA. PVA becomes=20
maximized over the Southeast while a surface low spawns along a=20
coastal front east of the Carolinas (with an additional surface low
moving out of the Bahamas). As the 850mb low deepens over northern
GA and heads east into SC, easterly 850mb theta-e advection will=20
direct low-level moisture around the 850mb low and support a band=20
of moderate-to-heavy snow from northeastern GA to central SC.=20
Farther north, the same tongue of 850mb theta-e is funneling along=20
the 850mb front to the north of the 850mb low track from northern=20
SC on east through much of NC. This is where the deformation zone=20
is likely to form, pivoting over central to eastern NC and northern
SC with 1-2"/hr snowfall rates likely. This band of heavy snow is=20
likely to reach farther east toward the Outer Banks (HREF=20
probabilities of >1"/hr at 00Z Sun, the end of the run, are >30%)=20
where 700mb FGEN is more ideally placed to support strong vertical=20 velocities within a fully saturated DGZ. These bands of heavy snow=20
in eastern NC and southeast VA depict 700-500mb lapse rates=20

6.5C/km Saturday afternoon and evening. It is here where not only=20

2"/hr snowfall rates are achievable, but so is the likelihood for=20 thundersnow. Note that the intense vertical velocities in eastern=20
NC and extreme southeast VA may result in some subsidence in north-
central NC and south-central VA. Snowfall is still likely to reach
warning criteria, but these regions are potentially susceptible to
lesser snowfall amounts as they are caught between the influence=20
of the strong upper-low to the south, and the strengthening coastal
low.

Speaking of the coastal low, along the VA/NC/SC coasts, not only=20
will the deformation zone of heavy snow pivot through, but the=20
explosive deepening of the storm east of Cape Hatteras will support
strong to potentially damaging wind gusts. ECMWF shows low=20
pressure south of Hatteras around 1008mb 12Z Saturday dropping to=20
around 970mb by 12Z Sunday east of Hatteras, indicative of rapid=20 intensification. With strong high pressure to the west, a strong=20
isallobaric flow will develop in response, creating wind gusts=20
along the DelMarVa coast on south through the Outer Banks that=20
could approach hurricane-force at times. These coastal areas=20
overlap with the ECMWF EFI in >0.8 values for both snow and wind,=20
making these areas most susceptible to blizzard conditions. Not to=20
be ignored either, strong wind gusts atop the Smokeys and Blue=20
Ridge are likely to top 60 mph as well, resulting in possible=20
blizzard conditions in those higher elevations of the southern=20
Appalachians. Power outages are likely in some parts of the=20
southern Mid-Atlantic, particularly areas at risk for those=20
hurricane-force wind gusts along the VA/NC coast.

Latest trends nudged the QPF footprint a bit southward but still=20
focused on NC into SC and grazing southeastern VA. By Sunday, the=20
trend of the system as it makes its closest pass to New England is=20
to be a bit farther southeast (away from the coast), and have=20
trended down the snow there in response. Locations that remain=20
susceptible are Cape Cod, Martha's Vineyard, and especially=20
Nantucket where WPC probabilities for at least 4 inches of snow are
around 50%.


Snowfall & Impacts...

For the event, WPC probabilities for at least 8 inches of snow are

50% from the Blue Ridge/Smokeys eastward across most of NC and=20

half of SC and along the VA/NC border. Eastern NC has the highest=20
chances (30-50%) of at least a foot of snow, depending on and band=20 placement. For context, some locations may see snowfall amounts not
seen since the 1970s/1980s (e.g., Feb. 1973, March 1980, or Dec.=20
1989) and could be a top ten event snowfall.=20

The snowfall could also be highly disruptive, not just during the=20
event, but for days after it is long gone. WSSI shows an expansive=20
area of Major Impacts (considerable disruptions to daily life;=20
dangerous to impossible travel, widespread closures, disruptions to infrastructure) from central SC (including Columbia, SC) through=20
the eastern two-thirds of NC (Charlotte/Raleigh-Durham). Along the=20
coast, WSSI shows Major to locally Extreme conditions from the=20
VA/NC border southward into the OBX and along the north and east-=20
facing shores of the Pamlico and Albemarle sounds, largely due the=20
blizzard potential and heavy snow. This speaks to the severity of=20
this major winter storm in the Carolinas. Lastly, with frigid=20
temperatures in the storm's wake on Sunday and lasting into=20
Tuesday, the snow will not melt much following the conclusion of=20
the storm. Any melting that occurs thanks to daytime heating is=20
likely to cause refreezing on untreated roads and surfaces.=20
Residents in the Carolinas should finish preparations as soon as=20
possible, as road conditions will be treacherous Saturday and into=20
the first half of next week.

Elsewhere, travel disruptions are possible as far south and west=20
as the Atlanta metro area where the WSSI shows Minor impacts with a
chance for an inch or so of snow on Saturday. Measurable snow may=20
cause hazardous travel as far west as the TN Valley and as far=20
south as Savannah where snowfall accumulations up to 1" are=20
possible. Moderate impacts (hazardous travel and some=20
infrastructure impacts) are also forecast in Charleston (SC), the=20 Smokeys/Blue Ridge of western NC/TN, and as far north as the=20
southern Richmond, VA suburbs. Impacts are still unclear in=20
southeast MA, but any snowfall will likely be accompanied by gusty=20
winds, causing blowing snow and reduced visibilities.=20


...Great Lakes...
Day 1...

Cyclonic flow will continue to favor lake effect snow across the=20
Great Lakes for another 36 hours or so. Frigid 850mb temperatures=20
will persist (around -18 to -24C, which are below the 10th=20
climatological percentile) over the rapidly freezing lakes. The N-S
band over Lake Michigan this morning will likely graze the WI/IL=20
shore before aiming into NW Indiana this evening/overnight as the=20
elongated vorticity lobe swings through. WPC probabilities for at=20
least 4 inches of snow are highest (40-60%) around Gary, IN.=20
Leftover lake snow on northerly flow will relax on Saturday as high
pressure briefly builds in from the west.=20


...Northern Great Plains, Upper Midwest, and western Great Lakes...
Days 1-3...

Tonight, a Pacific shortwave trough escorts Pacific moisture=20
eastward into the Northern Plains by Saturday morning, then into=20
the Upper Midwest Saturday evening into Sunday. Patches of freezing
rain in the northern High Plains on late Friday into Saturday are=20
expected given the favorable overrunning from WAA at low-mid levels
and sub-freezing surface temps. Farther east, snow is the more=20
likely precip type from the Red River of the North southward to the
Missouri Valley, then east to the Mississippi River and MN=20
Arrowhead/U.P/WI. Snow totals are forecast to range between 1-3" in
these areas late Saturday through Sunday into early Monday. Some=20
hazardous travel is possible, especially where roads temperatures=20
are likely below freezing in the wake of the recent extreme cold.


Fracasso/Mullinax


...Winter Storm Key Messages are in effect. Please see current=20
Key Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!_3gsfWHd4Rifi_CbV855Uh95BwMUxebkCOtdGLmsOVMQr= 5vQiqjacEqqVbSCNFdjb1Vfzm2V8IUKW9U7ZZxrzndtSh8$=20

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_2.png__;!!DZ3fjg!_3gsfWHd4Rifi_CbV855Uh95BwMUxebkCOtdGLmsOVMQr= 5vQiqjacEqqVbSCNFdjb1Vfzm2V8IUKW9U7ZZxr0nsBM1M$=20



$$

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FOUS11 KWBC 301835
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
135 PM EST Fri Jan 30 2026

Valid 00Z Sat Jan 31 2026 - 00Z Tue Feb 03 2026


...Southern Appalachians, Mid-Atlantic, & Southern New England...=20
Days 1-2...

...A major winter storm is expected to produce heavy snowfall and=20
blizzard conditions across the southern Mid-Atlantic...

The synoptic evolution continues to support a major winter storm,
primarily focused over the Carolinas, but questions about the
details continue.

The event begins this evening, as snow breaks out across the
southern Appalachians of NC/TN. This initial development of snow
will be in response to increasing synoptic ascent within strong
mid-level divergence downstream of a pivoting shortwave digging out
of the Great Lakes. As this shortwave dives southward out of the
Great Lakes, it will rapidly deepen into an impressive closed low
by 12Z Saturday over the Tennessee Valley, and then continue to
dive southeast, reaching the GA/SC coast by 00Z Sunday. This will
produce extreme anomalies of more than -5 sigma with respect to
500mb heights according to NAEFS across the Southeast/Gulf Coast,
indicative of how rare and extreme this setup will be. As the upper
low deepens and drops southward, forcing will intensify in response
to not only the mid-level divergence noted above, but additional
robust height falls, and increasing jet-level diffluence as a
downstream subtropical jet streaks strengthens across the Gulf and
then begins to arc poleward along the Southeast coast. This will
help generate surface cyclogenesis along the coast of the
Carolinas, with dual low-pressure systems progged, each one
deepening along the intense baroclinic gradient positioned offshore
owing to the recent extremely cold air blanketed across the eastern
CONUS.

The secondary surface low, which is likely to be the more intense
feature as it explosively intensifies Saturday night into Sunday
(maybe reaching into the 960s offshore) is progged to pivot more
east than northeast along the coast, so the heavy precipitation
should be generally confined to the Carolinas, southern VA, and
maybe Cape Cod as it pulls away. While there is continued
uncertainty into the exact amounts of precipitation due to dry air
aloft and intense mesoscale ascent that will drive bands of heavy
snow, there is high confidence in this overall synoptic evolution,
resulting in high confidence in the most impacted areas.

The column will be extremely cold, so other than possibly some
light rain along the coast to start the event, this will be an
all-snow scenario with above-climo SLRs, a rarity for this part of
the country. As noted above, the snow begins across the
Appalachians Friday evening and then expand rapidly to the south
and east as the upper low dives towards the Gulf and low pressure
development occurs offshore. This expansion of precipitation will
be driven primarily by increasing 850mb easterly flow, tapping into
the growing theta-e ridge offshore, with the resultant WAA leading
to the expanding snow shield, Some of this WAA could be intense as
reflected by strengthening 925-700mb fgen, well aligned into the
deep DGZ (>70% chance of at least 100mb of DGZ depth according to
the SREF). This will support not only expanding snowfall, but
intensifying snowfall such that by 00Z/Sunday at least moderate
snowfall rates should encompass nearly the entirety of the
Carolinas and into northeast GA and southern VA.=20

After 00Z Sunday is when the heaviest snow and most notable impacts
are expected as the low offshore deepens rapidly. This will pivot
winds to more N/NE across the region, and as a deformation axis
pivots west of the surface low and the cold conveyor sets up across
the Atlantic and into the eastern Carolinas, more intense ascent=20
and greater moisture should result in extreme (for this region)=20
snow rates. Cross-sections indicate a broad region of favorable=20
conditions for CSI, or even CI (thundersnow), and the HREF snow-=20
rate probabilities peak above 50% for 1"/hr suggesting at least a=20
potential for 2"/hr within a pivoting band somewhere in eastern NC=20
or SC, and this is additionally supported by the WPC prototype
snowband tool. These heavy snow rates will be accompanied by=20
strong winds that may gust 35-50 mph, higher at the coast and in=20
the mountains, suggesting near blizzard conditions in many areas.=20
While uncertainty remains into how dry air in the mid- level may=20
impact snow amounts on the broad scale, locally very significant=20
snowfall accumulations are likely, especially within these bands,=20
during D2. By Sunday afternoon the low will pull away bringing an=20
end to the snowfall and leaving just cold windy conditions in its=20
wake.

The exception will be across far southeast Massachusetts and onto=20
Cape Cod and the Islands where, despite a subtle southeast trend in
today's model guidance, periods of moderate snow are still expected
due to onshore flow and sufficient synoptic ascent into the
moistening column. A period of moderate snowfall is likely, with
some local enhancement south of Boston and on the Outer Cape due to
ocean influences, Sunday aftn/eve.

WPC probabilities for the event are quite robust for both the
Appalachians and eastern North Carolina, where they are above 50%
for 8+ inches, and 30-50% for 12+ inches. The greatest potential=20
for more than 12 inches appears to be eastern NC where the=20
deformation band may pivot, but a widespread 4-8" snowfall appears=20
likely from southern VA through northern SC, with impactful=20
accumulations expected in areas like Richmond, VA, Charlotte and=20
Raleigh, NC, Columbia, SC, and even into Atlanta, GA. Farther=20
northeast, WPC probabilities are 30-50% for 4+ inches across the=20
Cape and Islands.

Key Messages are in effect for this storm, and are linked below
(Key Message #2).=20


...Great Lakes...
Day 1...

Potent shortwave diving southward within broad cyclonic flow into=20
the Tennessee Valley Saturday morning will rapidly sharpen the
eastern CONUS trough leaving pronounced CAA on northerly flow in
its wake. This will result in continued lake effect snow (LES),
especially in the favored north snow belts south of Lake Ontario
and especially south of Lake Michigan where the long fetch of the
lake will be maximized to produce a narrow band of heavy snowfall.
Although the lakes are cooling and have much higher ice coverage
than a week or two ago, frigid 850mb temperatures moving overhead
will create strong delta-Ts to support snowfall rates that have a
30-40% chance (from the HREF) of exceeding 1"/hr, greatest across
NW Indiana. While some light accumulations are likely south of Lake
Ontario, WPC probabilities for 4+ inches are confined to NW IN
where they reach 30-50%.


...Northern Plains through the Upper Midwest and Great Lakes...=20
Days 1-3...

A shortwave emerging from the Pacific will crest the ridge over the
Pacific Northwest and then dive slowly southeast into the Northern
Plains and then amplify into a deeper trough as it moves into the
Great Lakes and then elongate towards the Tennessee Valley. This
feature will generally be of modest amplitude and remain
progressive, so large scale forcing for ascent will be modest and
driven by mid-level divergence downstream of the trough overlapping
modest warm advection/isentropic ascent. The result of this will be
axes of both light freezing rain and snow in many areas from
eastern MT through the western Great Lakes. WPC probabilities for
2"+ of snowfall are as high as 30-50% D2 across central/northern
MN, and similar for parts of the U.P. and western L.P. of MI D3.
For freezing rain, WPC probabilities are as high as 30% for 0.1"=20
in western ND on D1, but are generally less than 10% elsewhere=20
through the period. However, light freezing rain accreting above=20
0.01" is possible for much of Montana and the Dakotas.

Weiss



...Winter Storm Key Messages are in effect. Please see current=20
Key Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!_zv2HEUaCxHmrxcjxPpQ_d45hb_EFdwDQXzo01Egj7qkP= UXe0KoqO0O81tc8GJAqH6nRw9ZPdRN7lhhSqjXZph7rlAQ$=20

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_2.png__;!!DZ3fjg!_zv2HEUaCxHmrxcjxPpQ_d45hb_EFdwDQXzo01Egj7qkP= UXe0KoqO0O81tc8GJAqH6nRw9ZPdRN7lhhSqjXZerjYTzs$=20



$$

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FOUS11 KWBC 310710
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
210 AM EST Sat Jan 31 2026

Valid 12Z Sat Jan 31 2026 - 12Z Tue Feb 03 2026


...Southern Appalachians, Mid-Atlantic, & Southern New England...=20
Days 1-2...

...A major winter storm is expected to produce heavy snowfall and=20
blizzard conditions across the southern Mid-Atlantic...

Sharp mid-level trough over the mid-MS Valley early this morning=20
will close off into a potent upper low over Middle TN by 12Z. The=20
pattern over the East Coast will feature an increasingly amplified=20
pattern (e.g., strengthening S-shaped upper jet) that will support=20
explosive cyclogenesis off the Carolina coast this=20
evening/overnight. With an arctic air mass already in place, nearly
all of the precipitation will be snow even at onset. The system=20
will quickly lift up the coast (outside the 40/70 benchmark) and=20
clip southeastern New England as it races into Atlantic Canada=20
tomorrow.=20

First part of the system is underway over the southern=20
Appalachians with light to modest snow over the Smokeys into SW VA=20
beneath lower-level FGEN and incoming height falls/PVA. Snow will=20
expand southward today over WNC and Upstate SC as well as northeast
GA as the upper low tracks over ATL to CHS by this evening. To its
north, near the path of the developing 850mb low, the snow could=20
fall heavy at times today with 1"/hr rates possible (10-40% chance=20
per the CAM guidance) into the Charlotte metro. As the upper low=20
reaches the coast around 06Z Sun, banded snow could sink=20
southeastward into northeastern SC (Myrtle Beach/The Grand Strand).
By this time, the coastal low will have begun its rapid=20
intensification, which leads into the other part of the system.=20

With the coastal low intensifying through the 990s to 970s mb, N=20
to NE flow at the surface over eastern and northeastern NC into=20
extreme southeastern VA will increase as snow continues to fall.=20
The increasing 850mb northeasterly/easterly flow, tapping into the=20
growing theta-e ridge offshore, coupled with WAA and strengthening=20
925-700mb FGEN, will support >1"/hr rates over eastern NC after 00Z
Sun. Deformation axis should pivot west of the surface low and the
cold conveyor sets up across the Atlantic and into the eastern=20
Carolinas to support those rates. Cross-sections indicate a broad=20
region of favorable conditions for CSI, or even CI (thundersnow),=20
which is not unusual in highly dynamic and rapidly intensifying=20
systems. The column is quite cold, and SLRs should be well above=20
climo with a deep DGZ (>13:1 to near 20:1). These heavy snow rates=20
will be accompanied by strong winds that may gust 35-50 mph, higher
at the coast, suggesting near-blizzard conditions in many areas.

One question in the forecast, per the 00Z guidance, is what=20
happens in between these two main drivers of heavier snow areas;=20
i.e., in the I-85/95 corridors in NC. Some CAM guidance shows an=20
extreme min (near zero snow) while other guidance shows at least=20
several inches. CAM guidance could be overdoing the mesoscale=20
response of oscillatory subsidence/lift surrounding the system, but
it certainly is unusual to see this much spread just before the=20
start of the event. Trimmed down the amounts here from the previous
forecast but not to the extent of the 00Z CAMs.=20

By Sunday afternoon the low will pull away bringing an end to the=20
snowfall and leaving just cold windy conditions in its wake. To the
northeast, despite a track just outside the 40/70 benchmark, the=20
expansive system will likely clip far southeast Massachusetts=20
(southeast of I-95) and Cape Cod and the Islands where periods of=20
moderate snow are expected due to onshore flow and sufficient=20
synoptic ascent into the moistening column. A period of moderate=20
snowfall is likely, with some local enhancement south of Boston and
on the Outer Cape due to ocean influences, Sunday aftn/eve.

WPC probabilities for at least 6 inches of snow are >50% over much
of western NC, across the border to upstate SC, southeastward to=20
the coast, and the northeastward up the coast into extreme=20
southeastern VA. Lower probabilities around 30% exist along the VA=20
border and over southwestern SC. Mesoscale bands will likely=20
enhance snowfall over some areas resulting in >10-12" snow. A=20
broader area of light snow is expected surrounding the system, with
WPC probabilities for at least 1" of snow >50% as far west as=20
Atlanta, south to near Savannah, and on the north side up to=20
Richmond, VA and Salisbury, MD on the DelMarVa. In MA, WPC=20
probabilities for at least 4 inches of snow are >30% over the Cape=20
and Martha's Vineyard but >50% over Nantucket.=20


Key Messages are in effect for this storm, and are linked below=20
(Key Message #2).=20


...Northern Plains through the Upper Midwest and Great Lakes...=20
Days 1-3...

And advancing warm front over the western High Plains this morning
will continue eastward, bringing the chance for some snow and=20
freezing rain as milder Pacific air overruns the cold surface. The=20
system will continue eastward Sunday into the western Great Lakes=20
and through MI to the eastern Great Lakes Monday. Amounts will be=20
light, generally 1-3", as the system remains progressive. WPC=20
probabilities for at least 4" are around 10% over portions of the=20
Red River Valley (ND/MN border) and perhaps the Keweenaw Peninsula=20
wit some lake enhancement after the front moves to the east.=20


Fracasso/Weiss


...Winter Storm Key Messages are in effect. Please see current Key
Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!4XEwcjZbPCsaopLdDZHr3UrVyP5HfOPX16r-Ffei8ZPsV= DY7_6OXc-aU-DKV2da-bl6n6tCr8zwqm953Cu8HX5EO-2M$=20

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_2.png__;!!DZ3fjg!4XEwcjZbPCsaopLdDZHr3UrVyP5HfOPX16r-Ffei8ZPsV= DY7_6OXc-aU-DKV2da-bl6n6tCr8zwqm953Cu8H32009l4$=20



$$

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FOUS11 KWBC 311936
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
236 PM EST Sat Jan 31 2026

Valid 00Z Sun Feb 01 2026 - 00Z Wed Feb 04 2026


...Southern Appalachians, Mid-Atlantic, & Southern New England...=20
Day 1...

...A major winter storm will produce heavy snowfall across the
southern Mid-Atlantiuc and blizzard conditions along the North
Carolina coast through tonight and into Sunday morning...

The major winter storm is unfolding with periods of snow, falling=20
heavily at times, from the southern Appalachians and eastern GA on=20
east through the Carolinas and into far southern VA. This morning,=20
the 850mb low has formed and is tracking towards southern SC with a
tongue of rich 850mb theta-e air rotating around the northern and=20
western flanks of the low. As the low strengthens, so does the=20
easterly fetch supplying Atlantic moisture, resulting in a=20
broadening shield of snow from as far west as the Atlanta metro to=20
even as far south as Savannah, GA today. As strong 500mb PVA moves
in aloft, a band of heavy snow is likely to unfold over eastern GA
that could then pivot over southern SC, including the Charleston=20
metro area. The heaviest snow rates are likely to occur north of=20
the 850mb low track where easterly low-level winds are enhanced via
upslope flow from the hills near Charlotte on west into the=20
southern Appalachians. Snowfall rates of 1-2" per hour are likely=20
there, resulting in dangerous to even impossible travel conditions.
WPC probabilities show moderate chances (40-60%) for additional=20
snowfall totals >4" from Charlotte on south into central SC and=20
eastward to northeast SC and the Cape Fear Tidewater region.=20

Central NC and southern VA are caught between the impressive=20
dynamics closer to the highly anomalous upper-low to the south and
west, and the developing coastal low that will rapidly strengthen=20
east ot the Outer Banks today and into tonight. Guidance has come into
better agreement on a depression in the expected QPF footprint=20
around the Raleigh-Durham area on north and east along I-85 into=20 south-central VA. While totals have trended down, it is=20
exceptionally cold with highs unlikely to get above the mid 20s=20
today. Plus, occasionally gusty winds this afternoon and evening=20
will cause reduced visibilities and blowing snow on roads. WPC=20
probabilities still show moderate-to-high chances (50-80%) for=20
snowfall totals >2" in these areas, with better odds for >4" on=20
southward along I- 95 and I-40. Snow will have no trouble sticking=20
and travel will be hazardous through this evening and into tonight.
Expect slick roads to persist into Sunday as temperatures will=20
struggle to get above freezing, and any melting that does occur on=20
Sunday on roadways has a high chance to refreeze Sunday night and=20
Monday morning.

Farther east into eastern NC and southeast VA, the storm system
along the coast will rapidly strengthen by as much as 40mb in 24
hours. Not only will a band of 1-2"/hr snowfall rates ensue this
afternoon and into tonight, but wind will ramp up in intensity
significantly, especially along the Outer Banks and on north/east
facings shores of the Pamlico and Albemarle Sounds. Steepening
lapse rates as the mid-upper level low approaches the warmer shelf
waters will also support some instability in the 850-500mb layer,=20
allowing for thundersnow to be a potential phenomenon for those in=20
eastern NC. Snow will continue over the eastern tidal areas of NC=20
and southeast VA through early Sunday morning, but snow should=20
taper off by midday Sunday as the powerful winter storm races east=20
into the west Atlantic. WPC probabilities show moderate- to-high=20
chances (50-80%) for snowfall totals >6" from the Myrtle Beach area
and the Cape Fear region on north through much of eastern NC.=20
Given the robust 1-2"/hr rates in eastern NC, there is a low-to-
moderate chances (30-50%) for localized snowfall totals to surpass=20
12" by the time this event concludes late Sunday morning. As=20
mentioned above, the bitter cold in wake of the storm will keep=20
travel on all roadways across eastern and southern NC treacherous=20
into the start of the work/school week.=20

Lastly, trends have been to gradually decrease snowfall totals in
southeast MA, although some measurable snow and blowing snow is
likely over Martha's Vineyard, Nantucket, and the MA Capes. WPC
probabilities show low-to-moderate chances (30-60%) for snowfall
totals >4" here, with Nantucket sporting the highest chances for

6" given their closer proximity to the winter storm on Sunday.

Key Messages are in effect for this storm, and are linked below=20
(Key Message #2).=20


...Northern Plains through the Upper Midwest and Great Lakes...=20
Days 1-3...

An advancing warm front associated with low pressure over southern
Canada is tracking across the North Central U.S. today will=20
continue eastward, producing light snow and minor freezing rain in=20
the Northern Plains as milder Pacific air overruns the cold=20
surface. The warm front marches eastward Sunday into the Upper
Midwest and Great Lakes, then into Michigan and the eastern Great=20
Lakes Monday. Amounts will be light, generally 1-3", as the system=20
remains progressive. Another round of light snow arrives in the
northern High Plains on Monday and ending Monday night, but totals
are likely to be below 3 inches.


...Ohio Valley & Central Appalachians...
Day 3...=20

The shortwave trough responsible for light snow in the northern
High Plains on Monday dives south into the Middle MS Valley early
Tuesday morning and races into the OH Valley by Tuesday afternoon.
Weak 850-700mb WAA and a tongue of 700-300mb moisture aloft will be
available aloft and will allow for snowfall. Most snowfall amounts will
be generally a coating-2", although the central Appalachians in=20
eastern WV have low-to-moderate chances (30-50%) for snowfall=20
amounts >2". This weak feature has a chance to produce light snow=20
in portions of the Mid-Atlantic on Wednesday.


Mullinax



...Winter Storm Key Messages are in effect. Please see current=20
Key Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!_FsdXoLtiJKgZ9SEV8EVy4DoOUHafubqMkLCzThr-B36g= 9DWF1LlOJ9JGlBYJP21r3EHc_EHIKUVPBZmdQbPfoMGK1g$=20

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_2.png__;!!DZ3fjg!_FsdXoLtiJKgZ9SEV8EVy4DoOUHafubqMkLCzThr-B36g= 9DWF1LlOJ9JGlBYJP21r3EHc_EHIKUVPBZmdQbPrJyhzgw$=20



$$

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FOUS11 KWBC 010630
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
130 AM EST Sun Feb 1 2026

Valid 12Z Sun Feb 01 2026 - 12Z Wed Feb 04 2026


...Southeastern Massachusetts...
Day 1...

The powerful winter storm exiting the Carolinas this morning will=20
graze southeastern New England today with generally light snow but=20
very gusty winds. WPC probabilities for at least 4 inches of snow=20
are 10-30% over Nantucket and into parts of Cape Cod (e.g.,=20
Chatham).=20


...Northern Plains through the Upper Midwest and Great Lakes...=20
Days 1-3...

A surface front will move out of the Upper Midwest into the=20
western Great Lakes today then into Michigan and the eastern Great=20
Lakes Monday. Snow will be light, generally 1-3", as the system=20
remains progressive. Another round of light snow arrives in the=20
northern High Plains on Monday and ending Monday night, but totals=20
are likely to be below 3 inches. Some areas in the U.P. may see=20
several inches of the three-day period with modest lake effect snow
behind the front.=20


...Ohio Valley & Central Appalachians...
Day 3...=20

The shortwave trough responsible for light snow in the northern=20
High Plains on Monday will dive into the Middle MS Valley early=20
Tuesday morning and race into the OH Valley by Tuesday afternoon=20
and the Mid-Atlantic by Wednesday morning. Weak 850-700mb WAA and=20
mid-level moisture will favor light snowfall in a west-to-east=20
areas. Most snowfall amounts will be generally a coating-2", but=20
some upslope enhancement into the central Appalachians may allow=20
for a bit more. Here, WPC probabilities for at least 4 inches of=20
snow are low (10-20%). Light snow will extend eastward into the=20
Mid-Atlantic early Wednesday.


Fracasso


...Extreme Cold Key Messages are in effect. Please see current Key
Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!9GBpM9epRWaJGrcPUfEKW7ns0MQShIt24-3aSTYra4iBS= yEc4zdUJy3kS0uC9meUdSdqsB6te8uKUm4NjS4o-T7c-Og$=20


$$

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FOUS11 KWBC 011800
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
100 PM EST Sun Feb 1 2026

Valid 00Z Mon Feb 02 2026 - 00Z Thu Feb 05 2026

...Northern Plains through the Great Lakes...=20
Days 1-2...

A shortwave on the upstream side of an amplified trough (500mb
heights below the 1st percentile according to NAEFS) will dig
southeast from Saskatchewan while a secondary shortwave deepens
into a closed low over Ontario. Together, these features will drive
a surface cold front eastward from the Northern Plains to the Great
Lakes D1 before continuing into the Ohio Valley D2. The overlapping
ascent between height falls/PVA and low-level convergence, along
with modest frontogenesis and subtle WAA will result in an axis of
light to at times moderate snow, with the heaviest likely occurring
in response to lake enhancement east of Lake Michigan and across
the U.P. in the NW snow belts. WPC probabilities are modest overall
as available moisture is limited, but locally as much as 4" of snow
is possible (10-30%) across the U.P. and far NW L.P., with less
than 2" expected elsewhere. Additionally, some light freezing rain
is also possible driven by dryness within the DGZ, and WPC
probabilities for 0.01+" of ice are 10-30% across portions of the
Dakotas D1.


...Ohio Valley, Central Appalachians, and Mid-Atlantic...=20
Days 2-3...

A fast moving shortwave diving out of Alberta will drop southeast
around the western CONUS high and into the Mid-Mississippi Valley
Tuesday morning. This shortwave will amplify, at least subtly, as
it translates to the southeast, maintaining a positive tilt but
interacting with a cold front digging across the Ohio Valley. At
the same time, a subtropical jet streak draped along the Gulf Coast
will gradually intensity in response to the trough amplification,
and begin to pivot poleward, with the response to this evolution
being a surge in moisture lifting out of the Gulf noted by a strung
out theta-e ridge from the FL Panhandle into the Mid-Atlantic. This
moisture return will be aided by at least modest WAA, and the
guidance has trended upward just a bit in its QPF potential, and
has shifted northward somewhat as well.

The WAA lifting isentropically atop the cold front into the colder
airmass should result in a swath of light to moderate snowfall,
although locally heavier rates are possible due focused fgen into
the deepening DGZ, and this is reflected by significant spread in
the latest WSE plumes, despite a focus of mostly light snowfall
amounts. Current WPC probabilities are low (10-30%) D2 for at least
2 inches across the Central Appalachians of WV (where upslope
enhancement is likely), and moderate (30-50%) in that same area D3
suggesting localized totals of 4" are possible. Elsewhere, WPC
probabilities suggest moderate risk (30-70%) for more than 1 inch=20
across the lower Ohio Valley and a 10-30% for similar accumulations into
the Mid- Atlantic states including Washington, D.C.

Some light freezing rain is also possible with this wave as it
swings eastward, mostly due to loss of cloud ice vs warm nose
development, which could result in a swath of ice accretion above
0.01" (10-30% chance) from western KY/TN into VA/NC. Any ice is
hazardous, but this could be more problematic than usual due to
continued recovery efforts from the recent winter storms.


...Pacific Northwest...
Day 1...

A modest Pacific jet streak will lift northeast atop a west coast
ridge Monday, bringing with it a brief period of IVT exceeding the
90th climatological percentile according to NAEFS. A warm front
will push onshore and lift northeast concurrently with this jet
streak, leading to a brief period of enhanced WAA/precipitation
before snow levels climb rapidly into D2. This will result in a
period of rain and snow across the Washington Cascades, and
although snow level forecasts are generally above pass level, a few
inches of snow is possible between 3000-4000 ft before turning to=20
rain. WPC probabilities for 4+ inches of snow are above 70% only in
the higher Washington Cascades, but a few slushy inches of=20
accumulation is forecast at Stevens Pass leading to hazardous
travel Monday afternoon.

Weiss


...Winter Storm Key Messages are in effect. Please see current=20
Key Messages below...

https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late= stKeyMessage_1.png__;!!DZ3fjg!9YRGIGSlDRwz1Kt4s7H_JQxQxrQrLi-hlxXkhTcc2PeqV= OUwi_taivHgsFXvEnCrMLHMjTJRc9mduyxC6l5q8VK4ssU$=20



$$

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