Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
330 PM EDT Sun Aug 23 2026

Valid 00Z Mon Aug 24 2026 - 00Z Wed Aug 26 2026

...Dangerous and record-breaking heat continues across the south-central
U.S. into the Southwest...

...Isolated to scattered flash flooding and severe weather threat across
portions of the Southwest and into the Rockies/Plains, Upper Midwest, and
Southeast through Tuesday...


A strong and persistent upper ridge centered over south-central U.S. and
the Southwest will maintain very hot conditions across the southern tier.
Above normal temperatures will continue to have daily afternoon highs
within the upper 90s to 100s, with the highest values specifically over
much of Texas, Oklahoma, eastern New Mexico, and the Desert Southwest. The
combination of little to no overnight recovery and high humidity (for the
Southern Plains) will allow for heat indices to reach up to 105-115
degrees, which is where widespread Major to Extreme HeatRisk is forecast.
Furthermore, these abnormal temperatures are expected to break dozens of
high/low daily temperatures through the week. Extreme Heat Warning and
Heat Advisories have been issued across portions of the Four Corners,
Southern Plains, and Lower Mississippi Valley. The anomalous summer heat
wave is expected to persist through early this week and beyond. See the
latest Key Messages linked at the bottom of the discussion for more
information.

North of the ridge, a corridor of enhanced moisture and instability will
extend from the northern Rockies/Plains into the Midwest and Lower
Mississippi Valley. Shortwave energy embedded within the northwesterly
flow will interact with this moisture and a frontal boundary, resulting in
scattered thunderstorms through Monday. By Tuesday, a system will eject
eastward across south-central Canada and spread rain/thunderstorm chances
into the Upper Midwest. Repeated convection and high rainfall rates may
lead to excessive rainfall and isolated flash flooding, especially across
the Plains into the Lower Mississippi Valley. Additionally, Storm
Prediction Center highlights the potential for severe thunderstorms,
damaging wind gusts, and hail across portions of the Great Basin and
Rockies/Plains through Monday. Further southwest, monsoonal moisture will
continue to bring daily thunderstorms across the Southwest, Rockies, and
Intermountain West, leading to excessive rainfall/flash flooding concerns
the beginning of this week.

Meanwhile, a surface low and associated frontal boundary affecting the
Northeast will gradually shift eastward, but additional upper-level energy
will support lingering showers and thunderstorms into Monday across the
Lower Great Lakes and northern New England. Some storms may become locally
strong where sufficient instability develops, which may lead to severe
weather and excessive rainfall concerns. Additionally, the trailing
frontal boundary stretching across the Southeast will bring chances for
severe thunderstorms, damaging winds, and excessive rainfall on a isolated
to scattered basis through Tuesday.


Oudit/Snell


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

Extreme Heat Key Messages available at:
https://www.wpc.ncep.noaa.gov/basicwx/basicwx...

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