• Major Winter Storm Expect

    From Dumas Walker@21:1/175 to All on Fri Jan 30 08:50:39 2026
    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 (21:1/175)