Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
220 PM EST Thu Dec 11 2025

Valid 00Z Fri Dec 12 2025 - 00Z Sun Dec 14 2025

...Drier weather for the Pacific Northwest but flooding effects to
continue...

...Record warmth across portions of the west, while arctic air surges
south into the Northern Plains and Upper Mississippi Valley Friday and
Saturday...

...A narrow band of moderate to heavy snows likely from the Mid-West,
Upper Ohio Valley into the Central Appalachians tonight, followed by a
second stripe of accumulating snows Friday from the Northern Plains
southeastward into the Middle Mississippi Valley...

...Ongoing Lake Effect snows diminish Thursday night but are
re-invigorated late Saturday into Sunday...


Precipitation continues to diminish Thursday across the Pacific Northwest
as the atmospheric river that has produced 5 to 10+ inches of rain has
come to an end.  While drier weather looks to be in store for this area of
the country through the upcoming weekend, the major to catastrophic
flooding effects are likely to continue for several days across portions
of  western Washington State and northwestern Oregon.

The cessation of the Pacific Northwest heavy rains are in response to the
continued amplification of the large scale flow across North America,
characterized by a building mid top 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. Both record high afternoon temperatures and
record high morning low temperatures are possible in locations from the
Southwest, portions of southern and northern California and the Great
Basin Friday and Saturday.

In contrast much colder temperatures are in store across the north central
to northeastern tier of the nation over the next few days.  The coldest
temperatures will be across the Northern Plains, Upper Mississippi Valley,
Mid-West region where arctic air will be pushing southeast for the end of
the week into this weekend.  Afternoon high temperatures will be 20 to 30
degrees below average on Friday and Saturday over the Northern Plains,
spreading into the Upper Mississippi Valley on Saturday. A few record low
afternoon highs possible Saturday over the Northern Plains/Upper
Mississippi Valley region, with more widespread record low afternoon
temperatures possible Sunday across the Ohio and Tennessee Valley regions.

Preceding the southeast push of the arctic air, a narrow band of moderate
to heavy snow is possible from the Mid-West into the Upper Ohio Valley and
Central Appalachians Thursday afternoon into Thursday night in association
with a fast moving area of low pressure moving west to east from the
Central Plains into the Ohio Valley and Central to Southern Appalachians. 
This will be followed by a larger area of moderate to heavy snows Friday
from the Northern Plains, southeastward into the Middle Mississippi Valley
associated with the aforementioned arctic air outbreak.

In the lee of the Great Lakes, the ongoing active lake effect snows
showers, associated with the initial area of cold air to sweep over the
Lakes yesterday and today, will begin to diminish this evening.  However,
lake effect snows will likely be re-invigorated late Saturday into Sunday
as the upstream arctic airmass pushes back across the Great Lakes.

Oravec

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