Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
359 AM EDT Wed Aug 13 2025

Valid 12Z Wed Aug 13 2025 - 12Z Fri Aug 15 2025

...Scattered showers and thunderstorms to persist across the eastern U.S.
into the Deep South with heavy rain possible today into tonight across the
southern Appalachians...

...Strong to severe thunderstorms are forecast for portions of the
northern Plains late Wednesday and into the upper Midwest Thursday to
early Friday...

...Heat is building across the central High Plains as HeatRisk is forecast
to locally reach extreme level in portion of central Florida...

Over the next couple of days, a series of cold fronts is forecast to
advance from the Midwest and across the Great Lakes toward the eastern
U.S.  Ahead of the cold fronts, a large area of warm and moist air already
present across the eastern U.S and into Deep South will be an ingredient
for scattered showers and thunderstorms that are expected to be most
active from late afternoon into the evening hours.  Heavy rain can be
expected to accompany the stronger storms through the next couple of days
in these areas.  The most favorable region for heavy rain to occur will be
across the southern Appalachians today into tonight as a plume of tropical
moisture is forecast to lift northeast from the central Gulf Coast toward
the higher terrain in the southern Appalachians ahead of an upper-level
trough.  In fact, the Weather Prediction Center has maintained a Slight
Risk (level 2/4) of excessive rainfall for today and tonight for this area.

Meanwhile, a low pressure system is taking shape cross southwestern Canada
and into the northern Rockies with a warm front lifting northward across
the northern Plains.  The dynamics of this system will raise the threat of
heavy showers and thunderstorms across the northern Plains, especially
from South Dakota into northern Nebraska where there the Storm Prediction
Center has highlighted a Slight Risk (level 2/5) of severe thunderstorms
with a concern for damaging wind gusts and isolated areas of large hail. 
As the warm front advances eastward and then collides with a cold front
pushing in from the Canadian prairies, the severe weather threat will then
head further east across the upper Mississippi Valley on Thursday and into
Friday morning.

Cooler temperatures behind this cold front will allow for temperatures to
gradually trend below normal across the northern High Plains and
especially the Northwest U.S. for the latter part of the week.  This will
bring a break from the heatwave that portions of the Intermountain West
have been experiencing as well.  However, the same hot weather that has
been over the West will shift east out into the central Plains and the
Midwest late this week.  This will bring a couple of days with high
temperatures reaching well into the 90s to locally over 100 degrees into
the High Plains.  Across the Northeast where it has been hot lately,
temperatures are forecast to gradually cool down as a threat of showers
and thunderstorms arrives just ahead of the cold front.  Across northern
Florida, a slight increase of heat and humidity is enough to raise
HeatRisk to extreme levels on Thursday and Friday as the Bermuda High
builds westward into the Sunshine State.

Kong/Orrison


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