Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
359 AM EDT Mon Sep 07 2026

Valid 12Z Mon Sep 07 2026 - 12Z Wed Sep 09 2026

...Strong to severe thunderstorms expected across the northern Rockies and
the northern Plains, with heavy rain threat across northwestern Montana
today, followed by strong thunderstorms across the north-central Plains
Tuesday...

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

...Scattered thunderstorms linger across the Southeast...

As a large high-pressure system brings fine and cool weather across the
Great Lakes and the Northeast this Labor Day, a low-pressure system is
spreading unsettled weather into the northern Rockies and the northern
Plains. This is in response to a deep upper-level low getting ready to
eject out of the northern Rockies toward southern Canada. Strong dynamics
associated with this weather system will bring scattered to widespread
strong to severe thunderstorms across the northern Rockies to the northern
Plains as today progresses.  The low-pressure system is forecast to
intensify and move into the southern prairies of Canada by tonight, but
the potent cold front trailing from the low center will bring a round of
strong to severe thunderstorms as the front sweeps through the northern
Plains today, reaching into the upper Midwest tonight. By Tuesday, the
southern portion of the front will lose some momentum, allowing showers
and thunderstorms to develop over the north-central Plains and advance
gradually into the upper Midwest by Wednesday morning. WPC is now
highlighting a slight risk of excessive rainfall across Iowa Tuesday to
early Wednesday. In addition, a slight risk of excessive rainfall is
maintained across northwestern Montana for today.

As the cool high pressure system continues to expand southward into the
eastern U.S. and encounters the heat dome anchoring over the country's
midsection, the frontal boundary will eventually stall before reaching the
Gulf Coast. This pattern will allow scattered thunderstorms to linger
across the Southeast, including the Sunshine State, through the next few
days. Meanwhile, much of the Northeast and Mid-Atlantic will enjoy a break
from the heat as high temperatures only reach into the mid-70s and low-80s
for the next couple of afternoons. Morning lows dropping into the 40s and
50s will bring a first taste of Fall across New England, with a
reinforcing surge of cool air reaching northern Maine Wednesday morning. 

Below normal temperatures beneath the upper low will expand across the
West for the remainder of this weekend into the new week as daytime highs
dip 10 to 25 degrees below normal, except for much of the Four Corners
region. In fact, below-freezing morning temperatures are expected across
the higher elevations as far south as northern California and the Sierra
Nevada peaks. Meanwhile, oppressive heat will continue through Labor Day
in the Nation's Heartland with the unrelenting upper-level ridge over the
nation's midsection. 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 today and into the work 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.


Kong/Asherman


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

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