868
FXUS01 KWBC 190749
PMDSPD

Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
348 AM EDT Thu Sep 19 2024

Valid 12Z Thu Sep 19 2024 - 12Z Sat Sep 21 2024

...Severe thunderstorms possible in the eastern Plains and Upper
Midwest today...

...Late-summer heat forecast from the southern/central Plains to
the Upper Midwest...

The main weather story for the next couple of days will be a
strong occluded low and frontal system bringing impactful weather
to the Plains and Midwest. The central low will gradually lift
north into southern Canada today while it pushes a strong cold
front across the eastern Plains and Upper Midwest. Precipitation
will taper off in Montana and the northern Plains by this
afternoon as the low moves farther away, and the focus for
precipitation will shift to areas ahead of the cold front. A line
of showers and thunderstorms is forecast to develop ahead of the
cold front today, and a wave of upper level energy moving over the
Upper Midwest will provide support for scattered severe
thunderstorm development this afternoon into tonight. The Storm
Prediction Center has highlighted portions of the Upper Midwest
and eastern portions of the central and southern Plains with a
Slight Risk of Severe Thunderstorms (level 2/4). Potential storm
hazards will include a couple of tornadoes, large hail, and
damaging wind gusts. Additionally, locally heavy rain in stronger
storms may result in isolated instances of flash flooding in the
Upper Midwest.

Showers and storms ahead of the cold front will push east into the
Great Lakes region on Friday, but the front will weaken as it
becomes separated from its parent low in Canada. Shower and storm
chances will also linger along the eastern seaboard as a low
pressure system strengthens offshore in the western Atlantic. The
main low will remain parked southeast of Cape Cod over the next
few days while a slow-moving cold front extends southwest to the
Florida Peninsula. Strong gusty winds will be possible over the
coastal waters in the vicinity of the central low, which has
prompted the issuance of Small Craft and Coastal Flood Advisories
along portions of the Mid-Atlantic and Northeast Coasts and Gale
Warnings for the offshore waters south of Cape Cod and Long
Island. This system will finally pull away from the East Coast by
Sunday, which will result in decreasing winds and precipitation
chances.

Calmer weather is expected for the West today, with some lingering
showers and storms under an upper low in the Great Basin and
California, then the next round of unsettled weather will arrive
with a southward moving frontal system Friday and Saturday.
Precipitation will spread from the Northwest and northern Rockies
south to the Four Corners Region by Saturday, and some wintry
precipitation will be possible in the higher elevations of the
Intermountain West. Precipitation chances will also expand again
across the Plains and portions of the Midwest late Friday into
Saturday as the frontal system pushes east of the Rockies.

Temperature-wise, late-summer heat will stick around in the
Central U.S. through the end of this week. Warm southerly flow
will keep high temperatures in the 80s and 90s from the
southern/central Plains to the Upper Midwest. Some areas in the
southern Plains could see near record highs today and Friday as
highs approach 100 degrees. Above average temperatures are also
forecast for the Great Lakes and interior Northeast underneath an
upper level ridge. Temperatures in the West will remain below
normal over the next few days in the wake of the Plains system and
the upcoming late week frontal system. Temperatures in the East
and Southeast will be near normal with highs generally in the 70s
and 80s.


Dolan


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




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