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

Valid 00Z Sun Sep 06 2026 - 00Z Tue Sep 08 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...

...Cool and unsettled Labor Day weekend expected across the western U.S...

...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 over the Canadian Maritimes is bringing a cool
air mass deeper into the northeastern U.S. As the leading edge of this
cool air mass pushes against the heat dome centered over the country's
midsection, rounds of strong to severe thunderstorms with scattered heavy
rainfall will be triggered from the Ohio Valley, central/southern
Appalachians, and Mid-Atlantic this afternoon. By tomorrow, the front will
settle farther southward, confining thunderstorm and heavy rain chances to
portions of the Southeast and Gulf Coast. 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 tomorrow. 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 slowly move further inland
across the northwestern U.S. where scattered showers and embedded
thunderstorms can be expected through the Labor Day weekend. As southerly
flow strengthens ahead of this system, monsoonal moisture is forecast to
lift northward into the Great Basin in the vicinity of a slow-moving
front. This pattern will lead to increasing coverage of showers and
thunderstorms over the Great Basin, with scattered flash flooding possible
possible from southern Nevada to central Utah tomorrow. 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.

Over the Northern High Plains, a low pressure system is forecast to
consolidate and deepen on Labor Day ahead of the aforementioned
upper-trough. This developing storm will interact with anomalous moisture
to yield an expansive shield of moderate to locally heavy rain on the
northern flank of the low over portions of the Northern Rockies. East of
the wrap-around rainfall, an approaching Pacific cold front could drive
strong thunderstorms across the Northern Plains, which spread eastward
into the Upper Midwest on Tuesday as the maturing cyclone drifts across
the Canadian Prairie.

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 through the rest of Labor Day weekend and next
week. 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.


Asherman/Kong


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...

--- MBSE BBS v1.1.7.2 (Linux-x86_64)
 * Origin: Outpost BBS * Johnson City, TN (618:618/1)