912
FXUS01 KWBC 180758
PMDSPD

Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
357 AM EDT Mon Aug 18 2025

Valid 12Z Mon Aug 18 2025 - 12Z Wed Aug 20 2025

...Rounds of thunderstorms with a flash flood threat for portions
of the Midwest and a severe weather threat for the
central/northern Plains Monday...

...Scattered thunderstorms expected across portions of the
Southeast and Four Corners/Southwest the next couple of days will
bring an isolated threat of flash flooding...

...Life-threatening surf and rip currents expected along the
beaches of the East Coast this week as Hurricane Erin passes by to
the east...

...Hazardous heat builds across parts of the Plains, Midwest, and
Mid/Lower Mississippi Valley through early this week...

Ongoing overnight thunderstorms are expected to continue across
portions of the Midwest today with another round of storms
expected later in the afternoon/evening hours as an upper-level
shortwave and accompanying slow-moving surface frontal system pass
through the region. Plentiful moisture/instability will contribute
to very heavy downpours (rain rates upwards of 2" per hour) with
widespread/potentially organized storms leading to long-duration
rainfall and the potential for several inches of rain. A Slight
Risk of Excessive rainfall (level 2/4) is in effect from the Upper
Mississippi Valley vicinity east to the Lower Great Lakes/greater
Chicago region for the threat of scattered instances of flash
flooding. Further west, additional storms are expected in moist
post-frontal upslope flow across portions of the central/northern
Plains. Stronger upper-level winds with an approaching trough will
provide enough shear for organized, potentially severe
thunderstorms, with the Storm Prediction Center highlighting the
region in a Slight Risk (level 2/5) for the threat of large hail
and damaging winds. A threat for isolated instances of flash
flooding exists here as well. The associated surface cold front
will progress southward on Tuesday, bringing a renewed round of
scattered to widespread thunderstorms across portions of the
Midwest/Ohio Valley west through the Middle Mississippi Valley and
into the central/southern Plains. Some isolated instances of flash
flooding will remain possible.

Scattered to widespread thunderstorms are also expected across
portions of the Southeast the next couple of days. One area of
focus will be from the coastal Mid-Atlantic south through the
Carolinas and into the southern Appalachians along a
quasi-stationary frontal boundary draped through the region.
Additional storms are likely across Florida and westward along the
central Gulf Coast. Locally heavy downpours may lead to some
isolated instances of flash flooding. Farther west, surges of
monsoonal moisture into the Southwest/Four Corners region will
continue to spark daily isolated to scattered showers and
thunderstorms, some of which will be capable of producing
downpours and spotty instances of flash flooding. This will
especially be the case near burn scars and steep terrain.
Elsewhere, the Northeast and the Interior West/West Coast should
remain mostly dry.

Life-threatening surf and rip currents are expected for many of
the beaches along the East Coast this week as Hurricane Erin
begins to track northward and pass by to the east. In addition,
interests along the Outer Banks of the Carolinas should keep
monitoring Erin`s forecast track as there is a risk of strong
winds associated with the outer rainbands mid-week, as well as a
threat for significant coastal flooding and beach erosion.

Conditions will remain very hot and muggy over portions of the
southern Plains, Midwest, and Mid/Lower Mississippi Valley through
the early part of this week. Heat Advisories cover much of the
region as heat indices top out in the 105-110 degree range. In
addition, lows in the mid-to-upper 70s will bring little relief
from the heat overnight. Across the Northeast and Mid-Atlantic, a
cold front will bring relief on Monday after a hot weekend as
highs fall into the 70s for most locations. This relief from the
stifling heat and humidity should last through most of the week.
Elsewhere, forecast highs will also remain seasonably hot and into
the 90s across the Southeast, Gulf Coast, and northward through
the Plains through mid-week. A growing upper-level ridge will
bring hotter temperatures to the Rockies/Intermountain West as
well with highs rising into the 90s to near the triple digits
Monday into Tuesday. Meanwhile, portions of the Great Lakes north
of a frontal boundary will remain unseasonably cool, with highs in
the 60s and 70s. Temperatures across the West Coast will also
remain below average through midweek, with 60s and 70s expected.

Putnam


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