FOUS11 KWBC 160911
QPFHSD

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

Valid 12Z Fri Jan 16 2026 - 12Z Mon Jan 19 2026

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

Longwave trough re-establishes over the Great Lakes today where it
persists into next week as multiple shortwave troughs swing through.

An arctic cold front currently pushing across ND will push
south-southeast into the Midwest today. Strong frontal CAA will
continue to provide sufficient ascent for widespread snow showers
and likely additional snow squalls both along the front as it
moves across the rest of the north-central Plains through the
Missouri River Valley today and potentially IL/IN this evening.
Potent snow streamers in cloud streets/horizontal convective rolls
in the NW flow behind the front should also trigger snow squall
warnings particularly over SD/Neb this morning through midday.
Some particulars on the linear bands include alignment
parallel to the flow within a region of elevated 0-2km fgen,
increasing low- level moisture, and steepening lapse rates where
winds at the top of the PBL exceed 50 kt. Snowfall in these
potentially lingering/repeating banding could become locally heavy
and when combined with the strong winds will create near zero
visibility and dangerous driving.

Key Messages are being updated for these snow squalls with the link
at the bottom of this discussion.

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

The potent wave with the Arctic front has a leading cold front
currently over IA/KS which will swing east to the Appalachians
tonight and off the Eastern Seaboard Saturday with the Arctic
front quickly on its heels. The next reinforcing shortwave trough
then crosses the Great Lakes Sunday/Sunday night.
Renewed CAA across the Great Lakes today will reinstate LES with
more widespread coverage in snow belts as cold N/NW flow envelops
the entire region. Day 1 PWPF for >6" is 30-50% over the western
U.P., and the western L.P. This shifts to the Tug Hill and across
southern VT/NH for Day 1.5. Then Days 2 and 3 are highlighting
again over the western U.P. and western L.P.

...Ohio Valley, Appalachians, and Northeastern Seaboard... Days 1-3...

Progressive flow within a reloading and persistent mid-level
longwave trough will create active winter weather across the area
through the weekend.

The arctic cold front reaches the Ohio Valley late tonight and the
Mid- Atlantic states Saturday. Snowfall is likely through lift
along the front, followed by impressive upslope snow for the
Central and Southern Appalachians. Steepening lapse rates will
keep the DGZ relatively shallow, but sufficient ascent into the
moistened column will result in periods of moderate to heavy
snowfall with Day 1.5 PWPF for >4" spotty for 20-40% probs from
western PA through WV and the higher Apps along the TN/NC border.

Sunday and Sunday night an elongated lobe of vorticity will swing
into New England, while a secondary and sharpening shortwave dives
into the primary longwave trough across the Mississippi Valley.
While the lead impulse should bring snow to northern Maine (WPC Day
2 probabilities for 4+ inches 10-30%), the more challenging and
bigger concern will be what happens with moisture spreading
northward from the Southeast and along the Mid-Atlantic Coast
starting late Saturday night. Confidence is growing for light to
moderate snow from eastern VA through coastal NJ, Long Island, and
southern New England where Day 2.5 probs for >2" are 20-80%
(highest in on the central Jersey Shore. The low track is offshore,
so this is the backside precip.

...Southeast... Days 2/3...

A baroclinic leaf develops downstream of the digging, positively
tilted trough axis over the Mid-South Saturday night with strong
cold air advection and snow potential for the Southeast
Piedmont through the shortwave trough passage Sunday evening. This
is the southern extent of the more notable snow mentioned above for
the Mid-Atlantic. Day 2.5 snow probs for >1" are around 40% in
Southeast VA with some 20% reaching into central NC. While most
guidance has low to no snow, there are notable outliers like the
06Z NAM with decent snow from central GA through central NC. This
will continue to be monitored as the system gets into the CAMs today.

Jackson

...Winter Storm Key Messages are in effect and linked below...

https://www.wpc.ncep.noaa.gov/key_messages/LatestKeyMessage_1.png

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