Prognostic Meteorological Discussion
Issued by NWS

Home |  Current Version |  Previous Version |  Text Only |  Print | Product List |  Glossary On
Versions: 1 2 3 4
630
FXUS01 KWBC 082028
PMDSPD

Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
328 PM EST Mon Dec 08 2025

Valid 00Z Tue Dec 09 2025 - 00Z Thu Dec 11 2025

...Atmospheric river to usher in several days of heavy rain into
the Pacific Northwest and snow into the northern Rockies...

...Snow across North Carolina and Virginia is expected to taper
off this evening...

...A clipper will bring a period of snow across the upper Midwest
and the Great Lakes through Tuesday...

...A stronger clipper is expected to bring the threat of heavy
snow and high winds across the upper Midwest on Tuesday then
across the Great Lakes on Wednesday...

A weather pattern that supports heavy rain across coastal Pacific
Northwest will transition to cold and snowy weather for the
northern tier states. This will be in stark contrast with dry and
milder than normal conditions across the Southwest. In the
short-term, snow associated with an upper-level trough and a
developing low pressure system is in progress across North
Carolina and Virginia this afternoon. The low pressure system is
forecast to rapidly intensify and rapidly move off the
Mid-Atlantic coast tonight, which will bring the snow to an end
while dragging arctic air farther south into the East Coast
tonight with temperatures down into the teens Tuesday morning as
far south as North Carolina. The arctic chill will challenge some
low temperature records across the interior Mid-Atlantic to
southern New England Tuesday morning.

Meanwhile, a prolonged atmospheric river event is beginning to
take shape over the Pacific Northwest. The arrival of widespread
to heavy rain today signals the beginning of several days of heavy
rainfall expected to impact western Washington and northwestern
Oregon. The potent trans-Pacific jet stream will continue to
transport sub-tropical moisture from the Pacific and dump the
moisture as heavy rain closer to the coast, and more than a foot
of new snow for the northern Rockies in northwestern Wyoming.
Isolated to scattered instances of flash flooding are possible
near the coast and into the Cascades through midweek, where a slew
of Flood Watches are in effect.  Rainfall aside, parts of the
Pacific Northwest, northern Rockies, and northern Plains can also
expect very gusty winds through the next couple of days as the
same Pacific jet develops a strong clipper system in the Canadian
Rockies. As this clipper system ejects eastward into the northern
Plains and upper Midwest late Tuesday, a swath of moderate to
locally heavy snow is expected develop along the northern flank of
the low center.  Snowfall amounts of 4 to 8 inches can be expected
from northeastern corner of North Dakota through the central Great
Lakes.  This clipper system is forecast to quickly intensify,
producing an expanding area of very strong and gusty winds to
accompany the snow.  The snow will be tapering off across the
northern Plains on Wednesday behind the storm but snow will be
expanding through the lower Great Lakes and into interior
Northwest as the storm center approaches.  Rain will be falling
farther south across the Ohio Valley on Wednesday, moving into the
northern Mid-Atlantic later that day.

Prior to the aforementioned clipper, a weaker clipper will bring a
period of snow across the upper Midwest and the Great Lakes into
tonight and through Tuesday.  Meanwhile, the central and southern
Plains as well as the Deep South will enjoy fine and dry weather
with a warming trend especially for the Plains.  The Southwest
will remain dry and milder than normal while much milder than
normal conditions are forecast for the Northwest into the northern
High Plains along with the inclement weather.  A gradual drying
trend is forecast for the Sunshine State as a cold front pulls out
to sea.

Kong/Asherman


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

$$