670
FXUS01 KWBC 081910
PMDSPD

Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
309 PM EDT Fri Aug 08 2025

Valid 00Z Sat Aug 09 2025 - 00Z Mon Aug 11 2025

...Numerous flash floods -- some with significant impacts --
expected across portions of the Midwest Saturday into Sunday...

A robust upper-level trough moving slowly from the northern
Rockies through the northern Plains will trigger a dynamic low
pressure system from the central U.S./Canadian border into
south-central Canada through the next couple of days.  Its front
will essentially stall from Kansas northeast into Wisconsin from
tonight into Sunday night, becoming the focus for thunderstorms
with heavy rainfall and severe weather.  Hourly rain amounts to
2.5" along with multi-day rain totals to 9" are expected across
portions of the Midwest which have seen heavy rainfall during
recent weeks, leading to a new Moderate Risk area being depicted
across portions of southern Wisconsin, northwest Illinois, and
portions of Iowa this weekend.  Numerous flash floods, some with
significant impacts, are expected in this area.  Heat and humidity
will remain ahead of the stalling front, with cooler air from
Canada (with some Canadian wildfire smoke) lying in its wake.

The amplifying upper trough across Rockies will lead to dry,
breezy conditions for portions of Utah and Colorado, prompting Red
Flag Warnings for fire weather concerns there through Saturday.
For the Southeast U.S., a lingering frontal boundary near or just
off the coast combined with a moist air mass behind a
retrograding/westward-moving upper level low will keep enough low
level moisture and instability in place to fuel the development of
scattered showers and storms, with the greatest concentration
moving from northern Florida/southern Georgia westward along and
near the northeast and north-central Gulf coast Saturday into
Monday bringing a limited, localized risk of excessive rainfall.

Heat remains across the Desert Southwest, but with lesser
intensity this weekend into Monday, compared to recent days. Highs
across Arizona and eastern California deserts should still
approach, if not slightly exceed, 110F.  Across much of the East,
there will also be a gradual return towards August averages this
weekend into early next week, outside of the Southeast which
should remain somewhat milder than average due to the expected
rainfall/cloudiness.

Roth


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