749
FXUS01 KWBC 200717
PMDSPD

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
$$