Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
325 PM EST Thu Jan 21 2021

Valid 00Z Fri Jan 22 2021 - 00Z Sun Jan 24 2021

...Heavy snow for the Sierra Nevada Mountains, mountains of the
Great Basin, and the Central Rockies Friday through Saturday...

...Heavy lake effect snow downwind from Lakes Erie and Ontario
through Friday...

...Snow to develop over parts of the Upper Midwest Saturday...

A front extending across the interior Gulf Coast States will have
moisture pooling along the boundary and will produce rain from
parts of the Southern Plains eastward across the Southeast through
Friday.

Meanwhile, a reinforcing cold front will sweep across the Great
Lakes tonight, producing favorable cold westerly to northwesterly
flow across the unfrozen Great Lakes. Lake-effect snow showers
will increase in coverage and intensity this evening and continue
through Friday. Locally-heavy snow accumulations are likely with
the heaviest totals expected over western and northwestern
portions of New York State, downwind from Lakes Erie and Ontario;
northern portions of the Lower Peninsula of Michigan, downwind of
Lake Michigan; and along the north coast of the Upper Peninsula of
Michigan, downwind of Lake Superior through Saturday.

A front over the Pacific Northwest will advance southeastward to
the Southwest through Friday and into the Southern Rockies
Saturday. The system will produce coastal rain and higher
elevation snow over parts of southern Oregon through California
and snow across the Intermountain Region into parts of the
Northern Rockies through Friday. Later Friday, higher elevation
snow will develop over parts of Northern/Central California. The
higher elevation snow will expand across the terrain of the Great
Basin, Southwest, and Central/Southern Rockies along with lower
elevation rain. The rain will also shift into Southern California
on Friday evening. By Saturday morning, the rain and snow will end
over the Pacific Northwest and most of Northern California, yet
continue over Southern California, the Sierra Nevada Mountains,
and the Great Basin into the Central/Southern Rockies.

Overnight Friday through Saturday, a front over South-Central
Canada will move southward into the Upper Midwest. In conjunction
with upper-level dynamics over the Central/Southern Rockies, snow
will develop over parts of the Northern/Central Plains into parts
of the Upper/Middle Mississippi Valley.

Ziegenfelder

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