FXUS01 KWBC 230725
PMDSPD

Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
324 AM EDT Wed Jun 23 2021

Valid 12Z Wed Jun 23 2021 - 12Z Fri Jun 25 2021

...There is a Slight Risk of severe thunderstorms over parts of
the Central Plains through Thursday morning...

...There is a Slight Risk of excessive rainfall over parts of the
Central Plains and the Middle Mississippi Valley Thursday through
Friday morning...

...Fire weather conditions forecast across the Great Basin...

A front that extends from the Southeast westward to the
Southern/Central Plains will be quasi-stationary through Friday.
Ample moisture pooling along the boundary will help produce
showers and thunderstorms along and near the front through Friday
over the Southeast and the Gulf Coast States. A second front
moving southward out of South-Central Canada will move toward the
Great lakes and stall overnight Thursday.  The boundary will aid
in producing showers and thunderstorms over the Upper Midwest
through Friday.  The SPC has issued a Slight Risk of severe
thunderstorms over parts of the Central Plains through Thursday
morning.  The hazards associated with these thunderstorms are
frequent lightning, severe thunderstorm wind gusts, and hail.

The severe thunderstorm threat increases from Thursday into
Friday. The SPC has issued a Slight Risk of severe thunderstorms
over parts of the Central Plains and the Middle Mississippi Valley
through Friday morning.  The hazards associated with these
thunderstorms are frequent lightning, severe thunderstorm wind
gusts, hail, and a few tornadoes.  The excessive rainfall threat
increases on Thursday, too.  With the forecast of heavy rain, the
WPC has issued a Slight Risk of excessive rainfall with these
thunderstorms over parts of the Middle Mississippi Valley from
Thursday into Friday morning.  The associated heavy rain will
create mainly localized areas of flash flooding, with urban areas,
roads, and small streams the most vulnerable through Wednesday
morning.

Meanwhile, a plume of moisture surges into the Southwest and
Southern California on Wednesday and waning by Thursday evening. 
Impulses of upper-level energy moving around an upper-level high
over the U. S. and Mexican border will trigger showers and
thunderstorms over parts of Southern California and the Southwest
on Wednesday morning.  The showers and thunderstorms will expand
into parts of the Great Basin and the Central/Southern Rockies
through Thursday morning. Additional upper-level energy will come
over the top of the upper-level ridge producing showers and
thunderstorms over parts of the Northern High Plains into the
Great Basin and Central Rockies.  The showers and thunderstorms
will expand into the Northern/Central Plains on Friday.

Elsewhere, warm, dry, and windy surface conditions in the Central
Great Basin and Southwest will create favorable conditions for
fire weather, with a Critical Risk area encompassing much of
southern Wyoming. Additionally, dry thunderstorms with isolated
lightning strikes will be possible over the Northern Great Basin,
where dry fuels are present, creating another risk area for fire
weather. Red Flag Warnings are currently in effect for portions of
the Southwest, Great Basin, and Pacific Northwest with these
conditions in place.

Ziegenfelder

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