Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
400 AM EDT Sat Sep 05 2026

Valid 12Z Sat Sep 05 2026 - 12Z Mon Sep 07 2026

...Rounds of strong to severe thunderstorms and locally heavy rain will
slowly shift southward across the Midwest, Mid-Atlantic and into the
Southeast during the Labor Day weekend...

...A front moving through the western U.S. could trigger heavy rain across
Utah on Sunday...

...Heat persists across the midsection of the country while cooler air
expands further into the West Coast and the Northeast...

A deepening upper-level low in the vicinity of the Canadian Maritimes is
bringing a cool air mass deeper into the northeastern U.S. As the leading
edge of the cool air mass pushes against the heat dome across the
midsection of the country, a corridor of strong to severe thunderstorms
with scattered heavy rainfall will be triggered from the Midwest to the
Ohio Valley, central/southern Appalachians, and into the Mid-Atlantic
through the first half of Labor Day weekend. The most active thunderstorms
are expected to be moving through the Midwest to the Ohio Valley this
morning, followed by the central/southern Appalachians and into the
Mid-Atlantic later today and into the evening. A slight risk of flash
flooding is forecast closer to the Mid-Atlantic coast later today. By
Sunday, the front will settle farther southward into the eastern U.S. This
will confine the best chance for the stronger thunderstorms and heavy rain
across the Southeast U.S. Behind the front, the cool air mass will break
the recent spell of heat in the Northeast and Mid-Atlantic, where high
temperatures in the mid-70s and low 80s can be expected by Sunday. Morning
lows dropping into the 40s and 50s will bring a first taste of fall across
New England for the latter half of the Labor Day weekend.

Meanwhile, a deep upper-level low continues to move further inland across
the northwestern U.S. where scattered showers and embedded thunderstorms
can be expected through the Labor Day weekend. Farther south, monsoonal
moisture will be lifted ahead of a slow-moving front. It appears that the
best chance of showers and thunderstorms will be later on Sunday across
the Great Basin, with locally heavy rain possible from southern Nevada
through Utah, where WPC highlights a Slight Risk (level 2/4) of excessive
rainfall. Urban areas, as well as dry washes and burn scars will be most
vulnerable to flooding. Temperatures beneath the upper-low will be cool
across the West this weekend as daytime highs dip 10 to 20 degrees below
normal. In fact, below freezing morning temperatures are expected across
the higher elevations as far south as northern California.

Across the northern Plains, a low pressure system is consolidating ahead
of the upper trough moving into the Pacific Northwest. Rounds of strong
thunderstorms are expected to develop across the northern Plains around
the north side of the system. The coverage and intensity of these
thunderstorms and associated heavy rain are forecast to increase during
the latter half of the Labor Day weekend especially across the northern
High Plains as the low pressure system intensifies.

In contrast, oppressive heat will continue through Labor Day in the
Nation's Heartland as an upper-level ridge remains anchored over the
midsection of the country. Heat indices of 105 to 110 degrees and record
warm overnight temperatures will be widespread across the Central/Southern
Plains States and Mississippi Valley this weekend. See WPC's Key Messages
for more information on the heat, limit afternoon outdoor activity if
possible, and stay hydrated regardless of your Labor Day plans.


Kong/Asherman


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

Extreme Heat Key Messages available at:
https://www.wpc.ncep.noaa.gov/basicwx/basicwx...

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