Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
216 AM EST Mon Jan 20 2025

Valid 12Z Mon Jan 20 2025 - 12Z Wed Jan 22 2025

...Dangerously cold temperatures in place from the Rockies to the East
Coast...

...Rare, significant winter storm to bring a swath of heavy snow as well
as areas of sleet and freezing rain to the Gulf Coast and Southeast...

...Extremely Critical Risk of Fire Weather for southern California
Monday...

A bitterly cold arctic airmass has overspread the interior western,
central, and eastern U.S. following a strong cold front passage over the
weekend. Forecast high temperatures Monday from the Great Basin/Rockies
east to the East Coast will be upwards of 20-30 degrees below January
averages, ranging from the negative teens and single digits in the
northern Plains/Upper Midwest; the single digits and teens in the Rockies,
central Plains, and Midwest; the teens and 20s for New England and the
Mid-Atlantic; and the 20s and 30s for the Great Basin, southern Plains,
and Southeast. Life-threatening wind chills of 30 to 55 degrees below zero
at times are expected across the Rockies, northern Plains, and Upper
Midwest through Tuesday morning. Wind chills of this nature pose an
extreme risk of hypothermia and frost bite to exposed skin. Sub-zero wind
chills will reach as far south as the south-central Plains and east into
the Ohio Valley through Wednesday. Numerous Freeze Warnings are in place
along the Gulf Coast and northern Florida as sub-freezing morning lows
will pose a risk to sensitive vegetation and exposed plumbing for
locations not as accustomed to harsh Winter temperatures. Unfortunately,
these conditions look to remain in place across the eastern and southern
U.S. through the next few days. Upper-level ridging expanding across the
northwestern tier of the country will bring relatively warmer, more
seasonable Winter temperatures to portions of the Great Basin/Rockies as
well as the northern/central Plains on Tuesday, with highs back into the
20s, 30s, and 40s.

In addition to the frigid temperatures, the combination of such cold air
reaching the Gulf Coast and a developing low pressure system will lead to
a rare, significant winter storm for the Gulf Coast States and Southeast.
Impacts will begin Monday evening across eastern and southern Texas,
spreading eastward along the Gulf Coast and through the Southeast through
Tuesday and Wednesday. Heavy snow is expected along and north of the
Interstate 10 corridor with swaths of sleet and freezing rain over
portions of southern Texas and southeast Georgia/northern Florida. Major
travel disruptions are likely and flight delays/cancellations are expected
given that these areas are not accustomed to impactful Winter weather.
Power outages in areas of significant snow and ice are possible, and will
exacerbate impacts from the frigidly cold temperatures that will also be
in place.

Conditions will remain closer to average temperaure-wise for the West
Coast, particularly in California where forecast highs are in the 50s and
60s. Unfortunately, the mild temperatures as well as low humidity and the
return of very strong winds will lead to dangerous fire weather conditions
for southern California Monday into Tuesday. The Storm Prediction Center
has issued a Critical Risk of Fire weather (level 2/3) for southern
California as gusts to 60 mph for lower elevations and 75 mph and higher
in the foothills are expected. An Extremely Critical Risk (level 3/3) is
in place for the sensitive, ongoing fire areas of the San Gabriel and
Santa Monica Mountains. 

Elsewhere, bands of heavy lake effect snow will continue the next couple
of days for favorable downwind locations of the Great Lakes with
persistent northwesterly flow in place. An upper-level wave will encourage
snow showers with some accumulations possible for portions of the
central/southern Rockies and Plains on Monday, while a clipper system
dropping south from Canada will bring snow showers to the northern
Rockies/Plains and Upper Midwest Tuesday into Tuesday night.

Putnam


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