Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
250 PM EST Fri Feb 21 2020
Valid 00Z Sat Feb 22 2020 - 00Z Mon Feb 24 2020
...Cold temperatures across the eastern two-thirds of the country will
gradually moderate this weekend...
...A Pacific storm system to impact the Southwest on Saturday, Central
Rockies/Plains on Sunday...
...Rain and mountain snow return to the Northwest on Sunday ...
The Lower 48 will continue to observe tranquil weather conditions through
this evening as a large dome of high pressure remains in control. Chilly
temperatures will be felt across the eastern half of the country tonight
and Saturday morning with the coldest anomalies located in the Southeast.
A few Freeze Warnings have been issued for parts of the Lower Mississippi
Valley and the Southeast early Saturday morning. As high pressure slides
eastward throughout the weekend, winds will shift out of the south and
southwest over the Nation's Heartland, Great Lakes, and Northeast leading
to the return of milder temperatures.
The first in a pair of Pacific storm systems to impact the U.S. arrives
late tonight in the Southwest as a low pressure system approaches the
region. This storm system will tap into a source of deep moisture
originating from the subtropical Pacific and send said moisture into the
Southwest on Saturday. In response, rain will develop across the Southwest
with thunderstorms also possible in portions of southern Arizona and New
Mexico. The heaviest rainfall looks to be concentrated in the higher
elevations of western New Mexico and south-central Arizona where rainfall
totals ranging between 1 and 2 inches is possible. A Slight Risk for
Excessive Rainfall has been issued for these areas due to heavy rainfall
rates potentially causing areas of flash flooding on Saturday. By Sunday,
this storm system will intensify in the Central Plains generating areas of
showers and a few thunderstorms. Look for mountain snow to fall from the
southern Sierra Nevada and the Wasatch to the Colorado Rockies this
weekend as well.
Further north, a separate Pacific storm system will cause an increase in
showers and and mountain snow over the Pacific Northwest on Sunday. The
Olympics and Cascades will receive more mountain snow while the valleys
and coastal areas see rain. The storm system will then track into the
northern Rockies Sunday night leading to more areas of mountain snow
through Monday morning.
Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php