Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
300 PM EST Fri Dec 12 2025

Valid 00Z Sat Dec 13 2025 - 00Z Mon Dec 15 2025

...Record warmth across portions of the west, while arctic air surges into
the eastern two-thirds of the country through the weekend...

...Another clipper will bring accumulating snow across the Northern Plains
to the Midwest and Ohio Valley through Saturday, then from central
Appalachians to possibly the northern Mid-Atlantic on Sunday...

...Lake effect snow re-invigorates this weekend...

...A break from the wet weather this weekend for the Pacific Northwest
before the arrival of the next round of rain on Sunday...

The weather pattern across the country this weekend will allow a break in
the atmospheric river across the Pacific Northwest as arctic air from
Canada will be unleashed into the eastern two-thirds of the country.  As
this weather pattern unfolds, another clipper low pressure wave will bring
a stripe of accumulating snow through tonight across the northern High
Plains to the northern Plains.  This snow will then spread swiftly from
the northern Plains to the Midwest on Saturday before moving into the Ohio
Valley toward the central Appalachians Saturday night behind an arctic
cold front.  By early on Sunday, the northern Mid-Atlantic can expect some
snow to develop before sunrise behind this arctic cold front with support
from the upper-level dynamics of a potent jet stream.  Blustery conditions
will also accompany the snow as the arctic rushes in behind the cold
front.  This surge of arctic air will challenge or break some record low
maximum temperatures especially where the snow is expected to accumulate. 
The arctic air will also bring a re-resurgence of lake-effect snows across
the Snowbelt downwind from the Great Lakes through the weekend.  The snow
should be last to taper off across the Mid-Atlantic during the day on
Sunday.  An arctic high pressure system diving into the Plains will make
for a frigid Sunday for much of the eastern two-thirds of the country. 
The exception will be near the Gulf Coast and much of the Sunshine States
where it will take some more time for the cold air to push out the showers
and embedded thunderstorms.

Meanwhile, the Pacific Northwest will experience a break from the recent
extreme wet weather this weekend.  Nevertheless, the major to catastrophic
flooding effects are likely to continue into the weekend across portions
of western Washington State and northwestern Oregon.  By Sunday, rain from
the next system is forecast to reach the Pacific Northwest.  Rainfall
amounts are expected to be light to locally moderate by later on Sunday
across western Washington, but mainly light across northwestern Oregon. 
The lull in the Pacific Northwest heavy rains is in response to the
continued amplification of the large scale flow across North America,
characterized by a building mid-to-upper level ridge across the West and a
broad deep upper low over the middle to eastern portions of the U.S.  This
amplified pattern will produce big temperature contrasts from west to east
across the Lower 48 going into this weekend.  Much above average
temperatures are forecast from the West coast, through the Southwest,
Great Basin, Rockies and into the Southern Plains.  The exception
continues to be in the central California Valley where low clouds and fog
are expected to remain stuck, keeping temperatures much cooler than
surrounding cloud free areas. Some record high afternoon temperatures and
record high morning low temperatures are possible in scattered locations
across the western states.


Kong/Oravec/Kebede

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