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...
Days 1-3...
...A major winter storm is expected to produce heavy snowfall
across the southern Mid-Atlantic, blizzard conditions along the
Mid- Atlantic coasts, & potentially heavy snow in southern New
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
southern Mid-Atlantic beginning Friday afternoon and continuing
into the weekend. Snow will begin as early as Friday morning
across the TN Valley and east to the southern/central Appalachians
due to low-level WAA, increasing PVA aloft, plus upslope
enhancement into the Appalachians. As the upper trough sharpens
over near the OH/MS Confluence, a robust >100kt 500mb jet streak
will place its divergent left-exit region over the southern Mid-
Atlantic and snow will envelop much of the Appalachians and
Piedmont of the Southeast come early Saturday morning.
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
over the Southeast while a surface low spawns along a coastal
front east of the Carolinas. As the 850mb low deepens over northern
GA and heads east into SC, easterly 850mb theta-e advection will
direct low-level moisture around the 850mb low and support a band
of moderate-to-heavy snow from northern GA to central SC. Farther
north, the same tongue of 850mb theta-e is funneling along the
850mb front to the north of the 850mb low track from northern SC
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
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
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
southeast VA depict 700-500mb lapse rates >6.5C/km Saturday
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
only will the deformation zone of heavy snow pivot through, but the
explosive deepening of the storm east of Cape Hatteras will
support strong to potentially damaging wind gusts. Latest ECMWF
shows low pressure south of Hatteras is around 1007mb at 12Z
Saturday, then by 12Z Sunday is 972mb east of Hatteras, indicative
of rapid intensification. With strong high pressure to the west, a
strong isallobaric flow will develop in response, creating wind
gusts along the DelMarVa coast on south through the Outer Banks
that could approach hurricane-force at times. These coastal areas
overlap with the ECMWF EFI in >0.8 values for both snow and wind,
making these areas most susceptible to blizzard conditions. Not to
be ignored either, strong wind gusts atop the Smokeys and Blue
Ridge are likely to top 60 mph as well, resulting in possible
blizzard conditions in those higher elevations of the southern
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
the Tri-state area. There remains a high degree of uncertainty over
southeast MA where the differences in the EPS-AIFS 75th and 25th
percentile snowfall outcomes south of Boston still are quite
striking. The locations that should still contend with periods of
snow are Martha's Vineyard and Nantucket given their closer
proximity to the snow shield.
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
back to 1870, Wilmington, NC has only observed 3 instances where
>12" of snowfall occurred: Feb 1896, Feb 1973, and Dec 1989.
The snowfall likely to occur across the Carolinas has a good
chance to be not just significant but historic and highly
disruptive, not just during the event, but for days after it is
long gone. WSSI shows an expansive area of Major Impacts
(considerable disruptions to daily life; dangerous to impossible
travel, widespread closures, disruptions to infrastructure) from
central SC (including Columbia, SC) through the eastern two-thirds
of NC (Charlotte/Raleigh- Durham). The WSSI-P shows low-to-
moderate chances (20-50%) for Extreme Impacts (per the WSSI
legend: extremely dangerous conditions, life saving actions may be
needed) in southern NC, including the I-95 corridor from
Fayetteville, NC to Florence, SC. Along the coast, WSSI shows Major
to locally Extreme conditions along VA Beach on south into the
northern OBX and along the north and east-facing shores facing the
Pamlico and Albemarle sounds, largely due the blizzard potential
and heavy snow. This speaks to the severity of this major winter
storm in the Carolinas. Lastly, with frigid temperatures in the
storm's wake on Sunday and lasting into Tuesday, the snow will not
melt much following the conclusion of the storm. Any melting that
occurs thanks to daytime heating is likely to cause refreezing on
untreated roads and surfaces. Residents in the Carolinas should
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
Ridge of western NC/TN, and as far north as the southern Richmond,
VA suburbs. Impacts are still unclear in southeast MA, but expect
blowing snow to cause reduced visibilities in the southeast MA
islands.
...Great Lakes...
Days 1-2...
Cyclonic flow will continue to favor lake effect snow across the
Great Lakes into the first half of the weekend. Frigid 850mb
temperatures will persist with temperatures around -18 to -24C,
which are below the 10th climatological percentile. WNW flow will
turn more northerly (even NNE for a time) as the sharp 500mb
shortwave passes over the Great Lakes tonight. On Friday, northerly
flow continues Friday with NNE flow possible into Chicagoland
carrying a LES band into the region overnight into Saturday.
Latest guidance has favored the heavier snow over far northwest
IN, although localized totals approaching 4" along the Lake
Michigan
shores in Chicago are possible. Most snowfall winds downs late
Saturday into early Sunday as surface high pressure builds in
overhead.
Single band off Lake Ontario will weaken starting this afternoon
but persist through Friday. For days 1-2, WPC probabilities for at
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
morning, with the Black Hills sporting low chances (10-30%) for
snowfall total over 4". By Friday night, a Pacific shortwave trough
escorts Pacific moisture eastward into the Northern Plains
Saturday morning, then into the Upper Midwest Saturday evening into
Sunday. Patches of freezing rain in the northern High Plains on
late Friday into Saturday are expected given the favorable
overrunning from WAA at low-mid levels and sub-freezing surface
temps. Farther east, snow is the more likely precip type from the
Red River of the North on south to the Missouri Valley, then east
to the Mississippi river and MN Arrowhead. Snow totals are forecast
to range between 1-3" in these areas late Saturday into Sunday.
Some hazardous travel is possible, especially where roads
temperatures are likely below freezing in the wake of the recent
extreme cold.
Mullinax
...Winter Storm Key Messages are in effect. Please see current
Key Messages below...
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