Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
300 AM EST Sun Dec 04 2022

Valid 12Z Sun Dec 04 2022 - 12Z Tue Dec 06 2022

...Heavy snow in the Sierras; snow spreading from northern and central
Rockies into the northern High Plains; isolated flash flooding possible in
parts of California and Southwest...

...Heavy rain threat increasing over Tennessee Valleys/interior Deep South
from Monday through Tuesday morning...

...Cold air being ushered into the eastern U.S. behind a front...

A fresh dose of cold air from Canada is being ushered into the eastern
U.S. early this morning behind a cold front.  A large high pressure system
centered over the mid-section of the country will build eastward to
provide fine and dry weather from the Midwest to the East Coast through
Monday.  Meanwhile, a low pressure system off the West Coast continues to
pump Pacific moisture onshore into California this morning.  This system
will be rather slow-moving as it dumps heavy snow into the Sierra Nevada
while periods of moderate rain, heavy at times, will impact the lower
elevations especially the northern coast of California for the next couple
of days.  The moisture will then be carried farther inland and
precipitated as snow across the Intermountain West and into the northern
and central Rockies through Monday.  By Monday night into early Tuesday, a
cold front dipping southward from western Canada will interact with the
Pacific moisture to bring a period of snow over the northern High Plains
as a low pressure wave forms along the front.

Farther south, another plume of moisture associated with the subtropical
jet stream is spreading an axis of enhanced rainfall this morning from
southern Arizona across New Mexico and into the southern High Plains where
temperatures are cold enough to support frozen precipitation.  This jet
stream will be instrumental in setting up a potential heavy rain event
across the interior Deep South into the Tennessee Valley during Monday and
especially Monday night into early Tuesday as the Gulf moisture is lifted
ahead of a warm front.  Rain is forecast to expand northeastward toward
the Ohio Valley and eventually reach the Northeast with mixed
precipitation possible Monday night and early Tuesday ahead of a cold
front advancing into the Midwest and across the Great Lakes.

Kong


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