584
FXUS01 KWBC 201947
PMDSPD

Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
346 PM EDT Thu Aug 20 2026

Valid 00Z Fri Aug 21 2026 - 00Z Sun Aug 23 2026

...Severe weather and flash flood threats across parts of the East
into tomorrow, with severe threats over the Central Plains on
Friday...

...Dangerous heat persists in the South while building into the
Southwest...

A couple of wavy cold front in the East will support and help
focus heavy rain, flash flooding, and severe weather across much
of the Mid-Atlantic this evening and into tonight. As daytime
heating and instability are maximized this afternoon, strong to
severe weather with embedded heavy rain will focus along a slow
moving boundary draped across the Mid-Atlantic. WPC highlights
this region with a slight risk of excessive rainfall. There an
embedded moderate risk for excessive rain/flash flooding for the
New York City metro region and central to northern New Jersey
where an area of low pressure exiting the coast could help to
enhance rainfall in this more flood prone region. The northern
part of this boundary should shift off the Coast later tonight,
but the southern portion should help to maintain the severe
weather and flash flood threat across the southern Mid-Atlantic
and parts of the Carolinas tomorrow. Both WPC and SPC highlight
this region in the respective excessive rainfall and convective
outlooks for Friday.

Over the midsection of the country, another round of severe
weather is possible for eastern Nebraska into Minnesota and
Wisconsin this afternoon into the evening ahead of a front
trailing from a low pressure wave moving across Minnesota into the
U.P. Michigan. SPC has outlined a slight risk of severe weather
for the area where the main threat will be large hail, and
isolated wind damage. On Friday, much of central and eastern
Nebraska will experience another round of severe weather as the
trailing front pushes southward. SPC highlights this region in a
slight risk. As this boundary is expected to be rather
progressive, flash flooding is not a threat, but heavier rainfall
is possible in stronger thunderstorms.

Meanwhile, monsoonal showers and thunderstorms will be most active
during the late-day hours across the Four Corners states, where
the WPC has highlighted a marginal risk of Excessive Rainfall
through the next couple of days.

The southern tier of the Lower 48 remains mired in a steamy
air-mass even by mid-to-late August standards. Record highs and
record warm minimum temperatures will be common from the Southern
Plains into the Southeast, with a few records into the Southwest
as well. Extreme Heat Warnings are in effect for much of the
Desert Southwest, with Extreme Heat Warnings and Heat Advisories
extending from the Southern Plains to Florida and the Southeast
Coast. Expect little to no overnight relief across these regions
as temperatures struggle to get below 80F in some locations. This
equates to widespread Major to Extreme HeatRisk. The heat should
finally moderate across the Southeast as a cold front moves into
the region on Friday, but this potentially dangerous heat wave
will continue even beyond the short range period for the Southern
Plains and expand over the Southwest as well. Please refer to Key
Messages issued by WPC for additional information on this event.


Santorelli/Kong


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




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