Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
208 PM EST Thu Feb 10 2022

Valid 00Z Fri Feb 11 2022 - 00Z Mon Feb 14 2022

...Great Lakes...
Days 1-2...

Area of low pressure will exit Manitoba and track through northern
MN/WI and the U.P. of Michigan tonight into tomorrow morning (day
1) near the left/poleward exit region of a 130kt jet streak before
weakening at the start of day 2. Warm advection ahead of the
system will bring widespread snow of a few inches followed by lake
effect snows in its wake across the western Great Lakes into day
2. Amounts will be light with the cold front (generally 1-3") with
higher amounts with the relatively short-lived lake effect bands
tomorrow afternoon into the overnight hours where more than 6
inches is likely in some areas of the U.P. Farther east, cold
front will being light snow to much of western/northern NY and
northwest PA, followed by more focused lake effect into the Tug
Hill region where several inches are likely.


...Northern Rockies/High Plains...
Day 1...
Southwest side of the upper trough over the Great Lakes will
support some light snow along/east of the Divide near the tail-end
of a couple cold fronts tonight into Friday. SD Black Hills have
the highest chance for more appreciable snow (perhaps 4-6 inches
or more) with a few inches expected over higher elevations of
MT/WY/CO.


...Mid-Atlantic/Northeast...
Day 3...
Digging 500 mb shortwave trough over the Mid-South Saturday
evening will move through the Southeast by early Sunday near the
entrance regions of the northern (130kt) and southern (110kt) jet.
Frontal boundary astride the coastal plain may carry a weak area
of low pressure just off the coast about which the models continue
to waver on intensity/phasing/track. Trend has been toward a
somewhat suppressed system but confidence is on the lower side
given the inconsistency. Regardless, broad forcing will support
rain/snow over the area Sunday as colder air pushes eastward,
enhanced over the central Appalachians/Blue Ridge in VA. Breadth
of ensemble solutions maintains a low chance (10-20% from MD
northeastward and 10-40% across eastern WV and western VA) of 4
inches or more of snow.


For Days 1-3, the probability of significant icing is less than 10
percent.

Fracasso