Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
242 AM EST Mon Nov 22 2021

Valid 12Z Mon Nov 22 2021 - 12Z Wed Nov 24 2021

...Holiday travelers thankful as Thanksgiving week kicks off on a tranquil
note across much of the Lower 48...

...Wet Monday morning along the East Coast; Wettest and snowiest
conditions in the Northwest; Lake effect snow showers in the Upper Great
Lakes...

...Chilly temperatures in the East, warmer trend in the Heartland;
Critical fire weather areas in the central High Plains and Southern
California...

As the holiday week gets off and running, much of the continental U.S.
will be devoid of hazards the first half of the week. This is due to an
expansive dome of high pressure in the Nation's Heartland making its way
east towards the East Coast by Tuesday. Before high pressure builds in,
however, an advancing cold front is responsible for passing up and down
the Eastern Seaboard this morning. A few thunderstorms are also possible
as the front traverses the Southeast today. Passing shower and
thunderstorm activity will race into the northwest Atlantic by Monday
evening. The region forecast to witness the most unsettled weather through
Tuesday night is the Pacific Northwest thanks to a frontal system ushering
in Pacific moisture as far inland as the Northern Rockies Monday night
into Tuesday. Coastal and valley locations will see occasional rounds with
showers while mountain ranges pick up measurable snowfall. By Wednesday
morning, the heaviest snowfall totals likely occur in the Cascades where
over a foot of snow in the highest of elevations is expected. Parts of the
Bitterroots and Lewis Range can also expect 6 to 12 inches of snowfall.
The interior Northwest will not be the only region observing accumulating
snow. The Upper Great Lakes will receive several inches of snow today as
cold air rushing over the warm Great Lakes activates the lake effect snow
machine downwind of Lakes Superior, Michigan, Erie, and Ontario.
Additional snowfall accumulations up to 6 inches is likely in Michigan's
Upper Peninsula with several inches possible just east of Lakes Erie and
Ontario. Lastly, scattered showers and minor mountain snowfall
accumulations are possible in the Four Corners region as a frontal
boundary approaches from the north and west Tuesday night.

It certainly feels like the Holiday Season is upon us in the East where
below normal temperatures look to set up shop through Wednesday morning.
The cold front responsible for this morning's scattered shower activity is
also injecting cold Canadian air into the eastern third of the country.
High temps today will struggle to get out of the 30s in parts of the Great
Lakes and Ohio Valley (high temp anomalies of 10 to 20 degrees below
normal) with the same scenario playing out in the Northeast on Tuesday.
Even in the Southeast, daily temperature anomalies of 10 to 15 degrees
below normal are anticipated into Wednesday. Farther west, a warm front
lifting across the Plains and Midwest results in considerably warmer
temps. Highs will soar into the 60s throughout the Great Plains today with
some areas getting into the 70s by Tuesday. Regarding other potential
hazards, the combination of dry conditions and gusty winds is a favorable
recipe for fire weather conditions in the central and northern High
Plains. In fact, a Critical Risk for fire weather is in place over
southeast Wyoming. Meanwhile, Southern California can expect one more day
of Santa Ana winds where Red Flag Warnings remain in effect through the
first half of Monday.

Mullinax

Graphics are available at
https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php