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FOUS11 KWBC 100814
QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
314 AM EST Sat Jan 10 2026

Valid 12Z Sat Jan 10 2026 - 12Z Tue Jan 13 2026


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

An upper-level low over northern MN this morning will project
healthy PVA over the Great Lakes, as well as strong 700mb Q-vector
convergence over northern MI and MI's Upper Peninsula (U.P.). A
plume of 700-300mb moisture wrapping around the northern flank of
the 700mb low will coincide within a TROWAL that focuses a band of
moderate-to-heavy snow over the northern Great Lakes. The storm
system will progress east into southern Ontario by Sunday morning
and snow will begin to taper off by late Sunday morning. Most
guidance shows anywhere from 4-8" of snowfall as far west as the
Porcupine Mountains of MI's western U.P. to the Hurons in the heart
of the U.P. and much of the eastern U.P.. Farther south, the
northern-most locations of Michigan's Mitten are forecast to
receive 4-8" of snowfall as well, with localized totals topping 10"
possible where lake-enhanced snow bands stick around longest. Snow
fall totals of 1-4" are also anticipated along the coast of WI and
the western most counties of MI. The WSSI shows Minor Impacts
across all these regions, suggesting residents are likely to
contend with hazardous travel conditions Saturday night and into
Sunday morning.

In wake of this storm system, two more Canadian clipper systems
will race towards the Great Lakes. The first brings light snowfall
to northern MN Sunday afternoon and then into the northern Great
Lakes Sunday night. It is moisture starved and progressive, so
totals will generally range between a coating-3". As that upper-
level shortwave trough heads for the Northeast on Monday, another
clipper over the Canadian Prairies will track into the Upper
Midwest Monday night. This system has a little more moisture to
work with, but boundary layer temperatures are milder and may
result in more of a snow/rain mix on Tuesday. Both wintry setups
will be closely monitored, but snowfall totals are likely to
produce minor snowfall totals rather than highly impactful amounts
at this time.


...Northeast, Ohio Valley, & Central Appalachians...
Days 1-3...

On the eastern flank of the approaching Great Lakes storm system, a
strong IVT topping 750 kg/m/s and an advancing 925-700mb WAA will
provide rich moisture and strong low-level forcing to produce
periods of snow and a wintry mix over the interior Northeast.
Freezing rain will be most common today in northern PA, the
Poconos, Catskills, Adirondacks, Berkshires, and Green Mountains.
Latest WPC probabilities show moderate chancres (40-60%) for ice
accumulations over one-tenth of an inch in the Adirondacks, Greens,
and Berkshires, whereas the rest of the listed areas are generally
expected to witness ice accumulations less than one-tenth. Farther
north, snow will be the more common precipitation type from the
northern Adirondacks and White Mountains through northern Maine.
This is due to their locations farther north of the storm track of
the primary low in Ontario, and their placement north of a
secondary coastal low in the Gulf of Maine. The coastal low will
deepen southwest of Nova Scotia on Sunday and support a
deformation zone of heavy snow over northern Maine through Sunday
night. Snow should finally taper off by Monday morning, although
some blowing snow may still be ongoing across Maine. WPC
probabilities show high chances (>70%) for snowfall totals >6" in
northern Maine with low chances (10-30%) for some localized areas
near Caribou that could receive as much as a foot of snow.

This storm system over the Great Lakes will also be responsible for
other winter related hazards over the Ohio Valley and central
Appalachians. Ahead of an approaching 500mb vort max, a sharp low-
level cold front and healthy PVA aloft will support the development
of snow squalls Saturday afternoon as far west as Iowa that race
east towards northern IL and IN Saturday evening. Snow squalls will
race east through the OH Valley Saturday night and reach the Upper
OH Valley and central Appalachians by early Sunday morning. Light
accumulations of a coating to 1" are possible, but the concern is
rapid reductions in visibilities due to a combination of heavy snow
rates and gusty winds. Surface temperatures will also plummet below
freezing and could support quickly accumulating snowfall on roads.
Motorists should ensure they have a way to receive alerts for snow
squall warnings should they be issued.

Meanwhile, as the aforementioned cold front and snow squalls reach
the central Appalachians Sunday morning, upslope NWrly flow will
foster heavy mountains snow in the Potomac and Laurel Highlands
Sunday and into Sunday night. WPC probabilities show moderate-to-
high chances for snowfall totals >2", but there is a lower chance
scenario (10-30%) where the peaks of the Appalachians in eastern WV
and western MD receive as much as 4-6" of snow. Lastly, westerly
flow off Lakes Erie and Ontario will trigger lake effect snow bands
over the Chautauqua Ridge and over the Tug Hill Plateau Sunday and
into Sunday night. WPC probabilities depict moderate-to-high
chances for snowfall >4" through Sunday night. There will be
another chance for additional light snow over the Adirondacks and
Whites on Monday, but aside from the Tug Hill, snowfall will
generally be between a coating to 2" through early Tuesday morning.


Mullinax



$$

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