Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
236 AM EDT Tue Aug 26 2025

Valid 12Z Tue Aug 26 2025 - 12Z Thu Aug 28 2025

...Scattered areas of flash flooding remain possible across
pockets of the Intermountain West through Wednesday...

...Rounds of heavy rainfall are anticipated across portions of
Colorado, New Mexico, Kansas, Oklahoma, into the Mid-South through
Thursday...

...The Pacific Northwest will be hot again today; cool conditions
for late August expected mainly east of the Rockies....


Out West, through Thursday, monsoonal moisture, diurnal heating,
and upper-level impulses will produce showers and thunderstorms
over portions of the West. Slight Risks of excessive
rainfall/flash flooding exist across portions of the Southwest on
Tuesday and Idaho/northern Utah today and Wednesday.   The main
concern is flooding of dry washes/arroyos, urban areas, burn
scars, and box canyons due to scattered showers and locally heavy
thunderstorms that are most active late afternoon into the early
evening hours.  From late Tuesday into Wednesday, showers and
thunderstorms are expected to develop and become more numerous
across the northern Great Basin to the northern/central Rockies
due to the arrival of a slow-moving upper trough.  Meanwhile, warm
core ridging across the Northwest will aid and abet a heat wave
across Northwest continuing today before losing its grip on
Wednesday.  Daily record highs will once again be challenged this
afternoon as temperatures soar to near 100F at the hottest
locations.  This heat will be dangerous, posing a threat to anyone
without effective cooling and adequate hydration.  In addition,
there will be little nighttime relief from the extreme heat, with
overnight lows remaining well above normal.  Stay informed and
take steps to protect yourself from heat-related illnesses.  For
information on staying cool and safe, visit
www.weather.gov/safety/heat.

From portions of the High Plains through the Plains into the
Mid-South, elevated convection with heavy rainfall north of a
front will develop at times over parts of Colorado, New Mexico,
Oklahoma, Kansas, and the Mid-South through Thursday with a Slight
Risk of excessive rainfall depicted over portions of these areas. 
Hourly amounts to 2.5" would be problematic in urban areas. 
Swaths of heavy rain each day are expected to increase soil
saturation over time, making areas increasingly sensitive to
further heavy rainfall.  Across portions of Kansas/Oklahoma, the
ArkLaTex and Red River Valley of the South on Tuesday, and into
Kansas on Wednesday, and in and near northern Arkansas Thursday,
highs may only reach into the 60s and 70s threatening record cold
high temperatures for the dates as rainfall holds down daytime
temperatures.


East of the Rockies and north of the Gulf Coast, large swaths of
below average temperatures are expected to prevail, with
temperatures more reminiscent of early fall than late summer under
the aegis of strong high pressure (by August standards).  Cool to
cold conditions are expected overnight from the Gulf Coast
northward, with resplendent sunshine during the day over portions
of the Midwest, Appalachians, and much of the East today and
Wednesday, and across much of the Ohio Valley and portions of the
Mid-Atlantic States Thursday.  This morning, temperatures should
start off in the 40s and 50s across portions of the Midwest,
Kentucky, and the southern Appalachians, threatening record lows. 
Temperatures dip into the 40s and 50s across the east-central U.S.
threaten low temperature records from across the Midwest to the
Ohio and Tennessee Valleys, as well as the Mid-South Wednesday
morning.  On Thursday morning, record lows would be possible at
several sites from the Mid-Atlantic States into the Ohio Valley,
Southern Appalachians, and Gulf Coast as temperatures fall into
the 50s and 60s.  Near and east of the Great Lakes, cool air at
the surface and aloft triggers lake-effect and lake-enhanced
showers and a few thunderstorms through Thursday downstream of
mild to warm lakes; activity becomes more numerous as a
reinforcing front moves through late Wednesday into Thursday.

Roth/Kong


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