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... Days 1-3...
...A major winter storm is expected to produce heavy snowfall and
blizzard conditions across the southern Mid-Atlantic...
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 later this afternoon and continuing
into the weekend. Snow over the TN Valley this morning will move
into the southern/central Appalachians this afternoon due to low-
level WAA, increasing PVA aloft, and upslope enhancement. 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 early Saturday morning.
On Saturday, the 500mb shortwave will take on a N-S neutral tilt
over the TN Valley and close off as it enters NW GA. PVA becomes
maximized over the Southeast while a surface low spawns along a
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
direct low-level moisture around the 850mb low and support a band
of moderate-to-heavy snow from northeastern 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 much of NC. This is where the deformation zone
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
likely to reach farther east toward the Outer Banks (HREF
probabilities of >1"/hr at 00Z Sun, the end of the run, are >30%)
where 700mb FGEN is more ideally placed to support strong vertical
velocities within a fully saturated DGZ. 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
2"/hr snowfall rates are achievable, but so is the likelihood for
thundersnow. Note that the intense vertical velocities in eastern
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
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
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. ECMWF shows low
pressure south of Hatteras around 1008mb 12Z Saturday dropping to
around 970mb by 12Z Sunday 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.
Latest trends nudged the QPF footprint a bit southward but still
focused on NC into SC and grazing southeastern VA. By Sunday, the
trend of the system as it makes its closest pass to New England is
to be a bit farther southeast (away from the coast), and have
trended down the snow there in response. Locations that remain
susceptible are Cape Cod, Martha's Vineyard, and especially
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
half of SC and along the VA/NC border. Eastern NC has the highest
chances (30-50%) of at least a foot of snow, depending on and band
placement. For context, some locations may see snowfall amounts not
seen since the 1970s/1980s (e.g., Feb. 1973, March 1980, or Dec.
1989) and could be a top ten event snowfall.
The snowfall could also be 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). Along the
coast, WSSI shows Major to locally Extreme conditions from the
VA/NC border southward into the OBX and along the north and east-
facing shores of 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 shows Minor impacts with a
chance for an inch or so of snow on Saturday. Measurable snow may
cause hazardous travel as far west as the TN Valley and as far
south as Savannah where snowfall accumulations up to 1" are
possible. Moderate impacts (hazardous travel and some
infrastructure impacts) are also forecast in Charleston (SC), 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 any snowfall will likely be accompanied by gusty
winds, causing blowing snow and reduced visibilities.
...Great Lakes... Day 1...
Cyclonic flow will continue to favor lake effect snow across the
Great Lakes for another 36 hours or so. Frigid 850mb temperatures
will persist (around -18 to -24C, which are below the 10th
climatological percentile) over the rapidly freezing lakes. The N-S
band over Lake Michigan this morning will likely graze the WI/IL
shore before aiming into NW Indiana this evening/overnight as the
elongated vorticity lobe swings through. WPC probabilities for at
least 4 inches of snow are highest (40-60%) around Gary, IN.
Leftover lake snow on northerly flow will relax on Saturday as high
pressure briefly builds in from the west.
...Northern Great Plains, Upper Midwest, and western Great Lakes...
Days 1-3...
Tonight, a Pacific shortwave trough escorts Pacific moisture
eastward into the Northern Plains by 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 southward to the
Missouri Valley, then east to the Mississippi River and MN
Arrowhead/U.P/WI. Snow totals are forecast to range between 1-3" in
these areas late Saturday through Sunday into early Monday. Some
hazardous travel is possible, especially where roads temperatures
are likely below freezing in the wake of the recent extreme cold.
Fracasso/Mullinax
...Winter Storm Key Messages are in effect. Please see current
Key Messages below...
https://www.wpc.ncep.noaa.gov/key_messages/LatestKeyMessage_1.png
https://www.wpc.ncep.noaa.gov/key_messages/LatestKeyMessage_2.png
$$
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* Origin: Capitol City Online (1337:3/103)
