Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
414 PM EDT Tue Aug 25 2026

Valid 00Z Wed Aug 26 2026 - 00Z Fri Aug 28 2026

...Dangerous record-breaking heat continues across the South-Central U.S.
into the Southwest this week...

...Scattered instances of flash flooding (level 2/5) will be possible
Wednesday and Thursday across the Lower Mississippi Valley...

Strong to severe storms will be possible ahead of a cold front in the
Mid-South to the Ohio Valley tomorrow and into the Northeast on Thursday...

A strong upper-level ridge will remain anchored across the Southwest into
the South-Central U.S. into late week. This will maintain an abnormal
hazardous heat across the region. Daytime highs of 100-110 degrees F are
forecast across the Southern Plains for Wednesday and Thursday, while
portions of the Southwest will reach upwards to the upper 90s and low 100s
F in the valleys and 110s in the deserts. The urban areas of San Diego and
Los Angeles are under Heat Advisories and Extreme Heat Warnings through
the end of the week. With overnight temperatures providing limited relief,
heat-related illness may increase, especially for those without proper
hydration and adequate cooling. Accordingly, widespread Major to Extreme
HeatRisk is forecast for much of the Southwest into Texas through late
week. See the latest Key Messages linked at the bottom of the discussion
for more information.

An upper-level trough and surface cold front will begin to sweep eastward
across the Mid-Mississippi Valley to the Great Lakes tomorrow, sparking
chances for strong to severe thunderstorms capable of damaging winds and
hail. A tornado or two may also be possible on Wednesday in the Great
Lakes region, according to the Storm Prediction Center. On Thursday, the
severe weather threat (level 2/5) will shift to the Northeast for threats
of damaging winds, hail, and a tornado or two possible. Additionally, the
High / Central Plains into the eastern Rockies will see a chance for
strong to severe storms Wednesday and Thursday for mainly hazards of large
hail.

Across the Southwest and portions of the Rockies, monsoonal moisture will
continue to move northward along the western periphery of the ridge and
interact with embedded shortwave energy. This will lead to daily scattered
showers and thunderstorms Wednesday and Thursday. 1-2 inch an hour
rainfall rates with storms  will continue to pose isolated flash-flooding
concerns, particularly over sensitive terrain such as burn scars, slot
canyons, etc... Father east, increasing instability and persistent Gulf
moisture along a slow-moving frontal boundary will support repeated
showers and thunderstorms across the Southeast into Lower Mississippi
Valley. The Excessive Rainfall Outlook was bumped up to a Slight Risk on
Wednesday for portions of Arkansas, Mississippi, and Tennessee due to a
frontal wave enhancing the organization and coverage of storms. A Slight
Risk is also forecast on Thursday from Louisiana to South Carolina as a
stalled frontal boundary and shortwave energy interacts with summer
instability to produce the likelihood of locally heavy rainfall.

Lastly, the northern Rockies into the mountain ranges of the Pacific
Northwest will continue to see elevated fire weather concerns with above
average temperatures overlapping with low relative humidities and gusty
winds (10-30 mph). Follow local officials on fire weather orders.

Wilder/Oudit


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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