262
FXUS01 KWBC 210806
PMDSPD

Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
400 AM EDT Sun Jul 21 2024

Valid 12Z Sun Jul 21 2024 - 12Z Tue Jul 23 2024

...A break in the heat continues from the Plains to the East Coast
but more triple-digit high temperatures expected for the western
U.S....

...Scattered thunderstorms continue across the South and Southeast
will gradually lift northeast into the Mid-Atlantic and southern
New England during the next couple of days...

...Monsoonal thunderstorms linger across the Four Corners region
into the Great Basin...

...A cold front will bring new rounds of thunderstorms across the
northern tier states through the next couple of days...

A cool air mass settling in across the eastern two-thirds of the
country will offer an extended reprieve from the intense heat
through the next few days.  Afternoon high temperatures will only
reach into the 70s and 80s today from central U.S. eastward
through the Atlantic coast with the exception of the Sunshine
State and the coastal plain of Georgia and South Carolina, and
near the nation`s capital where highs will be in the 90s.  In
contrast, the heat across the western U.S. is expected to persist,
with high temperatures once again exceeding 100 degrees across
much of the region.  The interior Pacific Northwest will feel the
heat exceeding 110 degrees at the hottest locations by this
afternoon along with little overnight relief.  Daily highs across
the Southwest will remain in the 110s.  Please continue to
practice heat safety in this persistent and prolonged heat wave in
the western U.S. as we head into the new week.  A Pacific cold
front will approach the West Coast on Monday, lowering the heat
only slightly for inland sections.  By Tuesday, the front is
forecast to push farther inland into the Pacific Northwest.  In
response, the heat ahead of the front will begin to shift eastward
toward the northern High Plains while a cooling trend will begin
near the coast.

The slow-to-evolve upper-level pattern that is sustaining the heat
in the western U.S. and the relatively cool conditions farther
east will also keep a front nearly stationary across the South and
into the Mid-Atlantic region.  This front will help focusing and
triggering more scattered thunderstorms from the Gulf Coast to the
Southeast through the next few days.  The expansive cloud cover
throughout the South into the East Coast will keep daytime highs
capped generally in the mid-upper 80s, which is several degrees
below normal.  Under this paatern, the weak upper trough will
slowly lift northeastward, bringing an increasing chance of
showers and thunderstorms into the Mid-Atlantic and southern New
England during the next couple of days.

For the Four Corners region into the Great Basin, monsoonal
moisture will continue to support on-and-off thunderstorms through
the weekend.  These storms will keep an elevated threat for
isolated to scattered flash flooding and severe weather, which may
result from the strongest of the storms.  Across the northern tier
states, a cold front arriving from central Canada will bring new
rounds of thunderstorms from the northern Plains to northern New
England during the next couple of days with temperatures averaging
near or slightly above normal through the next couple of days.

Kong


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