Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
412 PM EDT Thu Jul 18 2024

Valid 00Z Fri Jul 19 2024 - 00Z Sun Jul 21 2024

...Dangerous heat to expand across the Western U.S this weekend...

...Multiple areas of unsettled weather from the Four Corners to Upper
Midwest; Southeast to Mid-Atlantic...

The main headline for the Nation's weather story this afternoon remains
dangerous heat expected to build across the Western U.S this weekend,
where 38 million people are under heat alerts from the interior Pacific
Northwest to the Desert Southwest and California. As an upper-level ridge
amplifies tomorrow, daily high temperatures will begin the climb in the
90s and triple-digits, with little overnight relief expected. These brutal
temperatures could challenge numerous records across the region beginning
this weekend, ultimately leading to dangerous conditions as the heat looks
to stick around beyond this weekend.

Meanwhile, monsoonal showers and thunderstorms will continue through this
weekend east of the Four Corners region, which will bleed into the High
Plains and Upper-Midwest as some monsoonal moisture and disturbances drive
additional thunderstorms along and ahead of a lee-side trough. Not to be
outdone, a lingering frontal boundary forecast to meander northward will
also force daily thunderstorms across the Southeast and Mid-Atlantic. As
is usually the case this time of year, isolated to scattered flash
flooding and severe weather may result from the strongest storms owing to
the copious moisture and instability available.

Asherman

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