Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
259 AM EST Thu Jan 19 2023

Valid 12Z Thu Jan 19 2023 - 12Z Sat Jan 21 2023

...Winter storm continues for the Upper Midwest/Great Lakes Thursday with
heavy, blowing snow leading to dangerous travel conditions...

...Snow and a wintry mix expected for portions of the Interior
Northeast/New England late Thursday into Friday...

...Unseasonably warm temperatures for the Ohio Valley into the Southeast
Thursday...

...Light to moderate snow showers forecast for the Interior West as
temperatures remain well below average in the region...

An amplified pattern will continue with one upper-level trough moving from
the central to northeastern U.S. as another trough digs in the West. At
the surface, a low pressure system will move from the Middle Mississippi
Valley northeast through the Great Lakes during the day Thursday and into
the Interior Northeast by Friday morning, with a trailing cold front
pushing eastward towards the East Coast. Areas of heavy snow and a wintry
mix will continue to the north of the surface low track for portions of
the Upper Midwest/Great Lakes Thursday. Additional snowfall totals of
around 6-12 inches are forecast for portions of the Upper Great Lakes,
with locally higher totals over a foot possible. Much of the snowfall is
expected to occur over a period of a few hours, with intense snowfall
rates of 1-2" per hour and gusty winds, making travel difficult to
impossible. Some sleet and a glaze of freezing rain may mix in for
locations on the southern end of heavy snow axis, generally from central
Wisconsin and into the northern Lower Peninsula of Michigan. The snow will
begin to taper off from west to east through early Friday morning. 

Showers and thunderstorms will continue along the cold front from the Ohio
Valley/Appalachians southwestward through the central Gulf Coast into
Thursday afternoon. The rain is expected to taper off from the Carolinas
southward through Florida as the front approaches the East Coast. While
the rainfall should be on the lighter side, the Storm Prediction Center
has issued a Slight Risk of severe weather (level 2/5) for portions of
Ohio Thursday. Cooler air and higher wind speeds moving over the area as
the upper-level trough approaches will lead to strong shear and sufficient
CAPE for some supercells and organized line segments, with the threat of
damaging winds and a tornado. A coastal low is forecast to rapidly deepen
later Thursday helping to enhance precipitation chances for portions of
the Northeast/New Enlgand. Heavier rainfall is expected from coastal New
Jersey/New York east through southern New England. Further north, heavy
snow upwards of 4-8 inches is forecast from Upstate New York east through
Vermont, New Hampshire, and coastal Maine late Thursday and into the day
Friday. Locally higher totals over a foot are possible for higher
elevations of the Green and White Mountains. In addition, some
accumulating freezing rain is possible, especially for the Catskills,
Poconos, and Berkshires. 

High temperatures will remain above average for another day east of the
cold front, with 60s forecast for the Ohio/Tennessee Valleys as well as
the Central/Southern Appalachians and 70s to low 80s for the Southeast,
Carolinas, and Florida. A few record-tying/record-breaking highs are
possible from the Southern Appalachians into the coastal Southeast and
Carolinas. Highs in the 60s will remain pleasantly warm for the coastal
Carolinas south into Florida Friday as temperatures drop back to average
for the Ohio and Tennessee Valleys, with upper 30s to low 50s forecast.
Cooler than average temperatures and breezy conditions are forecast to the
northwest over portions of the Central Plains as another surge of cold air
has pushed southward overnight Wednesday. Highs will be in the mid-20s to
mid-30s both Thursday and Friday.

In the West, a frontal system will continue to push southward through the
region as the upper-level trough digs aloft. Snow showers will move
southward through the Northern/Central Rockies and Great Basin Thursday
and into higher elevations of the Southwest and the Southern Rockies early
Friday. Snow totals will generally range between 2-4 inches, with locally
higher amounts for area mountain ranges. Some light rain will also move
through Southern California and into the Desert Southwest. Of more
significance for these areas will be the much below average temperatures
as the cold front pushes through and the upper-level trough expands over
the region. Highs Thursday and Friday will be in the 20s and 30s for the
Great Basin and the low to mid-50s for most of California and the Desert
Southwest. In addition, Freeze Warnings are in effect Friday morning for
many of the interior valleys and hills surrounding the Bay Area in central
California. Another low pressure system will begin to organize in the lee
of the Rockies late Friday as the upper-level trough begins to push
eastward over the Plains. While there remains some uncertainty on exact
amounts, accumulating snow is anticipated Friday night into the day
Saturday for portions of the Central/Southern High Plains.

Putnam

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