Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
321 AM EST Fri Jan 21 2022

Valid 12Z Fri Jan 21 2022 - 12Z Sun Jan 23 2022

...Significant icing across the coastal plains of the Carolinas today and
tonight; wintry weather this morning from southern Texas to the western
Gulf Coast...

...Arctic chill continues across much of the central and eastern U.S....

...Light snow across the northern Plains will move toward the upper Great
Lakes as snow showers across central Rockies move toward the southern
Rockies...

An arctic air mass has settled into much of the central and eastern U.S.
where much below normal temperatures are expected to prevail through the
next couple of days.  Bitterly cold conditions with subzero wind chills
are expected across much of the Upper Midwest and interior New England
where Wind Chill Advisories are in effect until early this morning. 
Meanwhile, below freezing daytime temperatures are forecast to be as far
south as upstate South Carolina today.  As the next upper level trough
from the central U.S. approaches the arctic front located just off the
southeast U.S., freezing rain and sleet are expected to develop across the
coastal plains of the Carolinas today and continue into tonight, resulting
in significant accumulations of up to a quarter of an inch possible. 
These locations are most at risk of downed trees and power lines.  Farther
north across eastern North Carolina into southeastern Virginia, snow and
some ice are expected to result in a few inches of wintry precipitation
accumulation before the system moves out to sea Saturday morning.

Meanwhile, southwesterly flow aloft overrunning the arctic air mass in the
South will support icy precipitation across southern Texas this morning. 
Ice accumulations of a tenth of an inch and/or a coating of snow are
possible in South Texas to the Texas Gulf Coast this morning before the
system shifts farther out into the Gulf of Mexico later today.

Elsewhere, an upper level disturbance tracking south through the
Intermountain West into the Great Basin will be relatively moisture
starved, limiting snowfall to the higher elevations of the Rockies with
totals surpassing 6" most likely in the highest peaks.  The upper
disturbance is forecast to evolve into a cut-off low by the time it dives
into the Desert Southwest on Saturday, keeping any rain and snow shower
activity confined to primarily Arizona and New Mexico.  Lastly, farther
north, a fast moving frontal system will trigger snow showers throughout
the upper Great Lakes on Saturday with light snow accumulations expected. 
Another wave of low pressure follows on its heels across the Dakotas
Saturday evening will bring more snow showers across the northern Plains
reaching the lower Great Lakes by Sunday morning.

Kong/Mullinax


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