Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
421 AM EDT Wed Aug 21 2019

Valid Wed Aug 21 2019 - Fri Aug 23 2019

...A front will focus thunderstorms in the Central Plains, Middle
Mississippi Valley, and Ohio Valley through Thursday...

...Severe weather and flash flooding are possible in the Northeast today...

...Another day of dangerous, potentially record-breaking heat across the
Southwest while heat and humidity persist across much of the country...

A frontal system is forecast to move slowly southward through the Central
Plains and Middle Mississippi Valley regions over the next couple of days,
and press eastward a little more progressively across the Ohio Valley,
Great Lakes region, and eventually through the Northeast. This front will
provide a focus for potentially multiple rounds of rain and thunderstorms
in the Central Plains to Middle Mississippi Valley today, southward into
Oklahoma on Thursday. Flash flooding is a threat with these storms, with
high rainfall rates and the potential for storms to repeat over the same
areas. Slight Risks of excessive rainfall/flash flooding are in place for
these areas, and some isolated severe weather cannot be ruled out.
Scattered showers and thunderstorms are possible farther south of the
front into the Lower Mississippi and Tennessee Valleys and Southeast as

Ahead of the main cold front, thunderstorms are likely in the Northeast
today as upper-level energy moves through. Severe weather and flash
flooding are both possible with these storms, and Slight Risks for both
threats are in place for today.

Dangerous heat is forecast once again in the Southwest, where high
temperatures in the mid-110s could set records. Temperatures in the 90s
are expected northward in the Intermountain West today. Farther east, Heat
Advisories are in place for portions of the Southern Plains to Lower
Mississippi and Tennessee Valleys, where heat and humidity could combine
to create high heat indices. The Eastern Seaboard will also remain warm.
Meanwhile, behind the cold front into the Northern/Central Plains and
Upper Midwest, below average temperatures are expected today. On Thursday,
the Ohio Valley and Lower Great Lakes region will cool down by several
degrees compared to Wednesday as the cold front passes.

Another cold front is forecast to move through the Pacific Northwest
today, bringing cooler temperatures and rain. Below average temperatures
will expand into the Northern Great Basin and Northern Rockies on Thursday.


Graphics available at:
NWS Weather Prediction Center Storm Prediction Center
United States 2 Day Forecast