Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
329 AM EST Wed Dec 22 2021

Valid 12Z Wed Dec 22 2021 - 12Z Fri Dec 24 2021

...Active weather with heavy mountain snow and lower elevation rain will
engulf much of the western U.S. during the next couple of days...

...Periods of snow over the Great Lakes as wintry weather over central and
northern New England today gives way to cold and blustery conditions
tonight...

...Persistent warm and dry conditions over the central U.S. with fire
danger over the Front Range...

The western U.S. is entering a period of increasingly unsettled weather as
moisture from a large decaying cyclone off the West Coast is forecast to
push onshore.  The precipitation currently moving into northern California
is only a preview of what is to come as another low pressure system near
the west coast of Canada is forecast to track toward the Pacific Northwest
during the next couple of days.  Active weather in the form of heavy
mountain snow and lower elevation rain will gradually engulf much of the
western U.S. through Friday morning under this weather pattern.  Major
mountain ranges such as the Cascades and especially the Sierra Nevada will
likely see snowfall to be measured in feet.  Farther inland, much of the
northern Rockies will eventually get 1-2 feet of new snow during the next
few days.  For the lower elevations along the West Coast, a couple more
inches of rainfall can be expected where the rain will be quite persistent
and heavy at times.

A low pressure system is currently edging gradually out into the Atlantic,
bringing an end to the rain across the Mid-Atlantic coast.  Meanwhile, a
coastal front is helping to focus a narrow zone of wintry precipitation
across central New England.  Another system, currently exiting the Great
Lakes, will help guide the wintry weather northeastward through northern
New England today resulting in 6 to locally more than 8 inches of snow
across northern Maine.  The snow should taper off to flurries tonight with
cold and blustery winds rushing in behind the departing storm.

Periods of snow can be expected over the Great Lakes where a stationary
front lingers.  Meanwhile, persistent warm and dry conditions are forecast
for the central U.S.  These conditions will promote fire danger especially
over the Front Range of the High Plains where downslope winds will prevail
for the next couple of days.  Temperatures will steadily rise above
average across the Great Plains toward the Great Lakes ahead of a warm
front as the large dome of warm air expands across the mid-section of the
country.

Kong


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