Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
400 PM EDT Wed Sep 08 2021

Valid 00Z Thu Sep 09 2021 - 00Z Sat Sep 11 2021

...There is a Slight Risk of severe thunderstorms and excessive rainfall
over parts of the Northeast/Mid-Atlantic through Thursday morning...

...There is a Slight Risk of excessive rainfall over parts of the Florida
Panhandle through Thursday morning...

...A heatwave will encompass much of the West with record high
temperatures possible...

A front extending from the Lower Great Lakes/Mid-Atlantic to the Southern
High Plains will slowly move eastward off the Northeast and Mid-Atlantic
Coast by Friday morning.  Showers and thunderstorms will develop along and
ahead of the front over the Lower Great Lakes/Ohio Valley into the
Mid-Atlantic and Southeast. Upper-level dynamics have led the SPC to issue
a Slight Risk of severe thunderstorms over parts of the
Northeast/Mid-Atlantic through Thursday morning. The hazards associated
with these thunderstorms are frequent lightning, severe thunderstorm wind
gusts, hail, and a few tornadoes.  Furthermore, heavy rain is associated
with these thunderstorms that will fall over areas where IDA produced
heavy rain. Therefore, the WPC has issued a Slight Risk of excessive
rainfall with these thunderstorms through Thursday.  The associated heavy
rain will create mainly localized areas of flash flooding, with urban
areas, roads, and small streams the most vulnerable. The severe
thunderstorm threat decreases to scattered thunderstorms on Thursday over
parts of the Northeast and the Atlantic Coast.  The excessive rainfall
will also decrease slightly over the Northeast.

Meanwhile, numerous showers and thunderstorms over the Central and Eastern
Gulf Coast will produce heavy rain over portions of the area.  Therefore,
the WPC has issued a Slight Risk of excessive rainfall over parts of the
Florida Panhandle with these thunderstorms.  The associated heavy rain
will create mainly localized areas of flash flooding, with urban areas,
roads, and small streams the most vulnerable through Thursday morning.

Elsewhere, an upper-level high over the Great Basin will aid in producing
record high temperatures over the Western States through Thursday, then
over parts of the Central Rockies and the Central/Southern High Plains on
Friday.  Furthermore, the dry weather associated with the upper-level high
will and gusty winds has led to an increase in the fire weather threat
over parts of the Northern Intermountain Region/Northern Rockies as a
Critical Risk of fire weather is posted. Red Flag Warnings over parts of
the Northwest into the Northern Rockies and Northern High Plains. In
addition, Excessive Heat Warnings are posted over Southeastern California,
southern Nevada, and parts of northwestern Arizona.  Heat Advisories are
also issued over most of California. However, Air Quality Alerts have also
been published over parts of the Pacific Northwest, Idaho, Wyoming, and
Colorado due to wildfire smoke. 

Ziegenfelder

Graphics are available at www.wpc.ncep.noaa.gov/basicwx/basicwx ndfd.php