Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
353 AM EDT Sun Jul 20 2025

Valid 12Z Sun Jul 20 2025 - 12Z Tue Jul 22 2025

...Widespread thunderstorms across the Northern Plains, Midwest,
Ohio Valley, and Southeast continue to pose a flash flooding and
severe weather threat...

...Severe storms likely across the Northeast today; scattered
thunderstorms in the Southwest may cause localized flash
flooding...

...Dangerously hot conditions to be found in the Central Plains,
Lower and Middle Mississippi Valley, and Southeast...

The weather pattern across the Continental U.S. is driven by a
ridge of high pressure over the Southeast and an active jet stream
across the northern U.S.. The position of high pressure over the
Gulf of Mexico and a longwave trough over the western U.S. will
sustain a steadfast low-level jet over the Southern Plains that
directs copious amounts of moisture northward into the Northern
Plains, Midwest, and Ohio Valley. This moisture will intersect a
frontal boundary over the Midwest and Ohio Valley that allows for
widespread thunderstorms today. The Weather Prediction Center
(WPC) has issued a Moderate Risk (threat level 3/4) for portions
of northeast Missouri and central Illinois where there is a
greater opportunity for locally significant flash flooding today.
Meanwhile, WPC has an expansive Slight Risk area (threat level
2/4) that stretches from northern Missouri and eastern Iowa to as
far east as the central and southern Appalachians, as well as
another Slight Risk in the eastern Dakotas. As a cold front pushes
southward through the Mid-Atlantic on Monday, the focus for
Excessive Rainfall will become more pronounced over the Ohio and
Tennessee Valleys where a Slight Risk has been issued. The
aforementioned cold front will also direct the plume of anomalous
moisture as far east as the Southeast on Monday where widespread
showers and storms pose a Marginal Risk (threat level 1/4) for
flash flooding. Lastly, as an upper-level trough over the Pacific
Northwest approaches, storms will pose a flash flood risk in the
Northern Plains on Monday, followed by the Upper Midwest on
Tuesday where there is a Slight Risk for flash flooding in
northern Minnesota, northern Wisconsin, and the western-most
communities of the Michigan Upper Peninsula.

This stormy pattern also contains several areas for organized
severe weather today. The Storm Prediction Center (SPC) has Slight
Risks (threat level 2/5) in place for portions of the Dakotas, the
Ohio Valley, and the Northeast. The Northeast Slight Risk area
contains urbanized metro areas such as NYC, Hartford, Providence,
and Boston. The severe storms could also lead to localized areas
of flash flooding in the urbanized Northeast corridor as well.
Severe storms today will be capable of producing damaging winds,
large hail, and tornadoes. SPC has a pair of Marginal Risks
(threat level 1/5) in the Northern Plains and the Southeast for
isolated instances of severe storms on Monday. Elsewhere, the
Southwest will contend with daily rounds of thunderstorms
containing torrential downpours. Localized flash flooding is
possible in parts of Arizona, New Mexico, West Texas, and Colorado
each afternoon and evening, especially along rugged terrain and
burn scars.

The aforementioned ridge of high pressure over the Southeast will
anchor in place the kind of searing heat and oppressive humidity
that occurs during the "Dog Days of Summer" from the Southern
Plains and Lower-to-Middle Mississippi Valley to the Southeast.
HeatRisk shows a large footprint of Major Impacts (level of heat
that affects anyone without adequate cooling and/or hydration) in
many of these regions through Monday. Heat indices throughout the
southeastern U.S. will range between 105-110F with some instances
where heat indices hover around 115F. Extreme Heat Warnings and
Watches are in place for parts of the Central Plains and Middle
Mississippi Valley that linger into the first half of the
work-week. There are also Heat Advisories for portions of the
Southern Plains, Lower Mississippi Valley, and along the Southeast
coast. The Southeast U.S. ridge will expand father north into the
Mississippi Valley by Tuesday, causing sizzling temperatures to
become stretch farther north into the Midwest by mid-week.


Mullinax


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