Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
359 PM EDT Sat Apr 22 2023

Valid 00Z Sun Apr 23 2023 - 00Z Tue Apr 25 2023

...Showers and storms with locally heavy rain linger in New England
Sunday-Monday...

...Areas of heavy rain and severe thunderstorms continue Sunday across
southern Texas...

...Frost/Freeze expected across portions of the Central Plains into the
Midwest Sunday morning...

...Mountain snow and coastal/valley showers will spread from the Pacific
Northwest Sunday into the Rockies Monday...

A frontal system will slowly push off the northeastern coast over the next
couple of days, with onshore flow over New England leading to continued
showers and thunderstorms Sunday that should taper off by Monday. Some
locally heavy rainfall is possible. Highs will be much cooler for the East
Coast behind the front after a couple weeks of much above average
temperatures. Highs will range from the 40s and 50s in New England, 50s
and 60s in the Mid-Atlantic, 70s in the Southeast, and 70s and 80s in
Florida. Further west, snow showers over the Upper Midwest/Great Lakes
should taper off overnight Saturday into early Sunday morning with little
to no additional accumulations expected. Temperatures will remain chilly
to the north of a surface front and under the influence of Canadian high
pressure with highs generally in the 30s and 40s Sunday. Some low 50s will
be possible Monday. Lows across the Northern Plains will dip into the
teens for some locations which, when combined with blustery winds, will
lead to some frigid wind chills.

Further south, showers and thunderstorms are forecast across portions of
Texas Sunday, with some more intense thunderstorms forecast to continue
along and ahead of a frontal boundary lingering around far south Texas. A
very moist, buoyant Gulf airmass will sit to the south of the front,
promoting locally intense rain rates. The tendency for storms to continue
to develop and back build along the boundary will also lead to longer
duration rainfall over the same areas. A Slight Risk of Excessive Rainfall
(level 2/4) has been introduced for the risk of some scattered instances
of flash flooding. In addition, strong enough winds aloft will support
sufficient shear for a few severe thunderstorms, and the Storm Prediction
Center has also issued a Slight Risk of severe weather (level 2/5) over
the same area as these storms may produce a few instances of large hail
and damaging winds.

To the north, much below average temperatures are forecast across the
Central U.S. Sunday. Highs will mainly be in the 50s and low 60s from the
Plains into the Mississippi Valley and Midwest, with only areas near the
Gulf Coast seeing highs reach the low 70s. In fact, many of the forecast
highs in the mid-50s across Texas are near or below record low maximum
temperatures for the date. Morning lows near freezing are forecast
Sunday/Monday morning for portions of the Middle Mississippi Valley into
the Lower Ohio Valley, with temperatures expected to drop below freezing
west into the Central Plains Sunday morning. Widespread frost/freeze
related advisories are in effect as these low temperatures may damage new
spring vegetation, and a few record lows may be broken.

A frontal system will approach the Pacific Northwest by Sunday morning
bringing lower elevation coastal/valley rain and some snow showers to
higher elevations of the Cascades. The system will push eastward through
the Great Basin and into the Rockies by Sunday evening. Upslope flow east
of the Rockies along with a fast-moving shortwave aloft moving
southeastward over the region will all lead to steadily increasing
precipitation chances through the forecast period. As we transition
further into Spring, snow chances will be isolated to higher elevations in
the mountains with some moderate accumulations possible. Lower elevations
will see rain along with the chance for some thunderstorms. Highs Sunday
and Monday along the track of the storm system through the Pacific
Northwest into the northern Great Basin and the Rockies will generally be
the 50s to low 60s. A ridge building in off the Pacific Coast will keep
temperatures warmer to the south, with highs in the 70s and 80s for most
of California and the southern Great Basin and 90s for the Desert
Southwest.

Putnam


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