Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
216 AM EST Tue Dec 05 2023
Valid 12Z Tue Dec 05 2023 - 12Z Thu Dec 07 2023
...Excessive rainfall and flooding potential continues across the Pacific
Northwest over the next few days...
...Moderate upslope snow forecast across the central Appalachians into
Wednesday...
...Warming trend increases across the Great Plains through midweek...
A strong atmospheric river impacting the Pacific Northwest is expected to
continue soaking the region with heavy rain through Wednesday until
precipitation becomes scattered. Warm air associated with the stream of
moisture extending from the subtropical Pacific will continue to allow for
very high snow levels through early Wednesday, which will exacerbate the
flooding potential due to snowmelt and increased runoff. Several
additional inches of rain are forecast across western Oregon and
Washington, as well as northern Idaho by midweek. Flood Watches, Warnings,
and Advisories have been issued for this part of the country. Residents
are advised to never drive through flooded roadways and have a plan if
within an area that typically floods. By Wednesday night into Thursday,
much of the precipitation should finally begin to weaken and shift
eastward throughout the northern Great Basin and northern Rockies, which
will allow for heavy mountain snow for many of the elevated ranges.
An Alberta Clipper system continuing its trek across the Nation will also
produce areas of snow from the Ohio Valley and Lower Great Lakes to the
central Appalachians into Wednesday. Snow will be mostly scattered and
light, except for the Allegheny Front of West Virginia and western
Maryland. Here, subfreezing temperatures and upslope flow from the
northwest will allow for moderate to locally heavy snow across the high
terrain. Winter Weather Advisories have been issued for the region
forecast to receive at least 3 inches of snowfall. Elsewhere, light snow
showers are possible across New England and light lake effect snow is
possible downwind of the Great Lakes through midweek.
The rest of the CONUS can anticipate dry conditions as high pressure
anchors overhead. Temperatures are forecast to remain slightly below
average along the East Coast and Southeast, while a warming trend kicks
off across the central United States. Highs on Wednesday and Thursday
should reach the 60s in the central Plains and 70s in the southern Plains,
with temperatures anomalies of 20 to 30 degrees above average extending
into the Middle Missouri Valley. Daily high temperature records will be at
risk of being tied/broken from Nebraska to Wisconsin on Thursday.
Snell
Graphics available at
https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php