Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
240 AM EDT Thu May 15 2025

Valid 12Z Thu May 15 2025 - 12Z Sat May 17 2025

...Severe thunderstorms possible for the Middle and Upper Mississippi and
Ohio Valleys today and Friday...

...Heavy rain and flash flooding possible for portions of the Ohio and
Tennessee Valleys on Friday...

...Dangerous heat forecast for portions of Texas...

A strong low pressure system will track into the Upper Midwest today,
supporting active weather for the Mississippi and Ohio Valleys and Great
Lakes region today and Friday. Widespread showers and thunderstorms are
forecast ahead of a strong cold front that will push east across these
regions, and conditions will be favorable for severe thunderstorm
development. Today, the highest severe thunderstorm threat will extend
from the Upper Mississippi Valley to the Great Lakes, then the highest
threat will shift to the Ohio and Middle Mississippi Valleys on Friday.
Scattered to numerous severe thunderstorms are expected, and hazards may
include large hail, damaging wind gusts, and tornadoes. 

Storm motion is forecast to be relatively progressive today, which will
help limit any flash flood threat from heavy rain, but slower storms on
Friday could result in scattered instances of flash flooding for portions
of the Middle Mississippi and Ohio Valleys. Isolated instances of flash
flooding will also be possible in portions of the Northern Plains today
where persistent showers on the backside of the strong low will result in
1-3 inches of rainfall. Additional flash flooding concerns will exist
today in portions of the Mid-Atlantic where scattered showers and storms
will linger as a weak frontal boundary lifts north across the region.
Recent heavy rains have saturated soils and resulted in impactful flash
flooding in portions of the Mid-Atlantic, and any additional rainfall
today could be problematic.

By Saturday, the strong low pressure system will pick up some eastward
momentum, pushing a cold front into the Eastern U.S. while a warm front
lifts into the Northeast. Chances for showers and thunderstorms will exist
across much of the East and extend back into the Southern Plains where the
tail of the cold front will briefly become stationary before lifting back
north as a warm front. Precipitation chances will also increase across the
Northwest on Saturday as an energetic Pacific frontal system pushes
onshore. Widespread showers are forecast with high elevation mixed
precipitation and snow possible in the Cascades and Northern Rockies.

Temperatures are forecast to cool across the North-Central U.S. as colder
air moves into the region behind the strong low pressure system. High
temperatures will likely be 10-20 degrees below normal, only reaching the
50s with some areas only reaching the upper 40s. Meanwhile, the
South-Central U.S. will be battling dangerous heat as high temperatures
soar into the 90s and 100s across Texas. Above average temperatures are
also forecast across the Midwest, Mid-Atlantic, and Northeast where highs
may reach the 80s and lower 90s today and Friday. Temperatures should
moderate in the Midwest and East on Saturday while below average
temperatures develop in the West as a frontal system moves onshore.


Dolan


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