Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
224 PM EST Fri Jan 20 2023

Valid 00Z Sat Jan 21 2023 - 00Z Mon Jan 23 2023

...New storm system to bring heavy snow to portions of the central High
Plains through Saturday...

...Unsettled weather with heavy showers and thunderstorms expected across
the Gulf Coast states and Southeast this weekend...

...Developing East Coast coastal low to bring a new winter storm to the
Northeast by Sunday night and Monday...

Some lingering light snow and snow showers can be expected this evening
across the Great Lakes and New England in the wake of low pressure exiting
well offshore of the Northeast. High pressure will be building across much
of the Midwest and stretching east across the Ohio Valley and toward the
East Coast by Saturday which will yield drying conditions and temperatures
that will actually be a bit above normal given a lack of cold air
advancing south from Canada.

While the Northeast gradually begins to dry out, the next storm system
will be dropping southeast across the Four Corners states tonight through
Saturday, and this will bring an axis of accumulating snowfall initially
across the central Rockies. A swath of heavy snow is then expected to
develop and spread east across portions of the central High Plains, and
areas of southeast Colorado and western Kansas are expected to see as much
as 6 to 10 inches of snow by Saturday evening. The northern portion of
this storm system will advance east and weaken somewhat as it crosses the
Midwest, Ohio Valley and Great Lakes through Sunday, but will still be
capable of producing a fairly large swath of at least light snow with
locally an inch or two possible by Sunday evening given at least
marginally cold enough temperatures.

However, farther south, the energy with this system will be focusing a
developing area of low pressure across the western Gulf of Mexico which
will advance northeast and cross the central and eastern Gulf Coast by
Sunday morning before then lifting up across the Southeast and the coastal
plain of the Mid-Atlantic states by Sunday night. This will yield a
sufficient return flow of warm air and moisture for areas of locally heavy
showers and thunderstorms to impact the Gulf Coast states and the
Southeast going through the weekend. As much as 1 to 2 inches of rain can
be expected with isolated heavier amounts. A very localized threat of
flash flooding and severe weather be possible on Sunday as a few stronger
thunderstorms cross the Southeast, and the Weather Prediction Center and
Storm Prediction Center respectively have issued a Marginal Risk of these
specific hazards. As this area of low pressure deepens along the East
Coast Sunday night and approaches the Northeast by Monday, there will be
an expanding area of moderate to locally heavy snow across the interior
sections of New York and New England just in time to start the new week.

Across the West, as the initial system dropping through Four Corners
region pulls away, strong high pressure will follow and temperatures
across much of the Great Basin and the Southwest will be below normal.
High temperatures will locally be as much as 10 to 20 degrees below normal
this weekend and the overnight lows are expected to drop low enough that
some of the interior valleys of California, including the San Joaquin
Valley, may see subfreezing temperatures. Precautions should be taken
accordingly to protect any sensitive outdoor agricultural interests. A new
cold front will dive southeast across the Intermountain West by the end of
the weekend, and this will help to reinforce below normal temperatures
heading into early next week.

Orrison

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