284
FXUS01 KWBC 121653
PMDSPD

Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
1251 PM EDT Sat Sep 12 2026

Valid 00Z Sun Sep 13 2026 - 00Z Tue Sep 15 2026

...Showers and thunderstorms continues across the Central and
Eastern U.S. ahead of a well-defined front...

...Pacific low pressure system will lead to wet and cool weather
across the Northwest and Northern Rockies...



The upper trough over Upper Midwest/Great Lakes will continue to
push the leading frontal boundary into Great Lakes/Ohio Valley and
extend across central U.S., while a warm front lifts into the
Northeast. The frontal boundary will interact with moist unstable
airmass, leading to showers and thunderstorm development along the
boundaries. The combination of instability, deep moisture, and
forcing, may lead to an elevated threat for excessive rainfall and
severe thunderstorms across portions of the Ohio Valley into the
Mid-Atlantic and central/southern Plains through the remainder of
today. On Sunday, the frontal system continues to slowly push into
the Northeast, while the trailing portion of the frontal boundary
over central U.S. lifts northward. This will promote a continued
threat of severe thunderstorms over portions of the Ohio Valley
into the Northeast and excessive rainfall over portions of the
Northeast and Midwest.

Across the Northwest, a upper trough will move into the region,
ejecting another frontal system leading to beneficial soaking
rains. Farther south, daily monsoon thunderstorms will continue
across the Southern Rockies and Four Corners, which may lead to
isolated flash flooding. As the Pacific system evolves, it is
expected to spin up a lee-side cyclone over the Northern and
Central Rockies. By tomorrow morning, a strong low-level jet
interacting with a northward-moving front will cause the Plains to
light up with showers and thunderstorms, introducing a risk of
isolated to scattered flash flooding. Rainfall aside, the frontal
passage(s) should usher in pleasant daytime temperatures over
portions of the Northern Tier, Great Basin, and High Plains with
highs in the low-mid 60s and 70s. Unfortunately, the upper ridge
will continue to persist for portions of the southern Plains into
the Mid-Mississippi Valley, as potential record-breaking heat will
continue to persist through the weekend.



Oudit/Asherman


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






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