Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
400 AM EDT Fri Jul 19 2024

Valid 12Z Fri Jul 19 2024 - 12Z Sun Jul 21 2024

...A break in the heat is expected for much of the eastern two-thirds of
the country but triple-digit heat will continue in the West through this
weekend...

...Scattered thunderstorms will be confined across the South and Southeast
as monsoonal thunderstorms  linger across the Four Corners region...

...Strong to severe thunderstorms possible today over the north-central
Plains...

A cool air mass arriving from central Canada is bringing a welcome relief
to the heat and humidity into the northeastern quadrant of the country
today.  Temperatures as high as the 100s a couple of days ago in the
Mid-Atlantic will only recover to around 90 degrees this afternoon with
lower humidity.  On the other hand, the heat across the western U.S. is
expected to persist through this weekend, with high temperatures once
again exceeding 100 degrees across much of the region.  In fact, the heat
is forecast to intensify over the interior Pacific Northwest, will
readings possibly reaching 110 degrees at the hottest locations by Sunday
afternoon with little overnight relief expected.  Meanwhile, high
temperatures well into the 110s will be common across the Desert
Southwest.  Please continue to practice heat safety in this persistent and
prolonged heat wave in the western U.S. throughout this coming weekend.

The upper-level pattern that supports the heat the West and the cooler
weather across the central to eastern U.S. will be slow to evolve through
the next few days.  A front that separates the cool air from the warm and
moist air along the Gulf Coast will remain stationary across the South. 
Scattered thunderstorms will be confined in the warm sector across the
South and Southeast where they will linger through the weekend. 
Meanwhile, monsoonal moisture will support thunderstorms across the Four
Corners region, lingering on-and-off through the weekend.  Isolated to
scattered flash flooding and severe weather may result from the strongest
storms.  Farther north, a weak low pressure wave will likely trigger
thunderstorms which could become strong to severe over the north-central
Plains today into tonight.  Additional thunderstorms are expected to track
farther east toward Iowa and Missouri during the weekend.

Kong


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