


Prognostic Meteorological Discussion
Issued by NWS
Issued by NWS
086 FXUS01 KWBC 170714 PMDSPD Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 313 AM EDT Fri Oct 17 2025 Valid 12Z Fri Oct 17 2025 - 12Z Sun Oct 19 2025 ...Showers and storms increasing in coverage from the Great Lakes to the Mid-South... ...Rain returns to Washington state by late Saturday... A developing low pressure system currently over the Dakotas will continue lifting northeast across western Ontario through Friday evening, with a lingering frontal boundary situated across the Upper Midwest and western Great Lakes region. A new wave of low pressure develops along this front over Wisconsin and into Michigan on Saturday into early Sunday, which becomes the next main weather maker from the Mid-South to the Great Lakes over the weekend. Showers and thunderstorms increase in coverage from Arkansas to eastern Michigan along and ahead of a strong cold front, with the heaviest rainfall expected from central Illinois to northern Indiana where 1-3 inches could fall, which may lead to some instances of flooding where convection is most persistent. Farther south from the ArkLaTex to western Kentucky, the Storm Prediction Center has a Slight Risk of severe thunderstorms in their outlook for Saturday, with a more favorable dynamical environment in tandem with higher instability. This could lead to some instances of damaging winds, large hail, and a few tornadoes with the strongest storms that develop. A Marginal Risk for severe weather extends farther north across the Ohio Valley. Elsewhere across the nation, it will be a crisp and cool end to the work week for much of the Eastern U.S. with a pristine airmass in place. Frost and freeze advisories/warnings are in effect for interior portions of the Mid-Atlantic and Northeast states. Across Montana, high winds will be possible starting Saturday night across northern portions of the state as a strong Pacific storm system approaches from the west, and rain and mountain snow reaches Washington state by Saturday afternoon and beyond. Dry conditions will continue for all of the southwestern U.S. and the East Coast states as high pressure continues to govern the overall weather pattern through Saturday. Hamrick Graphics available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php $$