Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
245 PM EDT Mon Sep 15 2025

Valid 00Z Tue Sep 16 2025 - 00Z Thu Sep 18 2025

...Slow moving coastal low to bring heavy rain potential along the
Mid-Atlantic coast...

...Heavy rains possible across the Central to Northern Plains Tuesday and
Wednesday...

...Tropical moisture from Mario to begin to push into Southern
California...

...Below average temperatures likely where wet weather occurs next two
days, otherwise above average temperatures expected across much of the
CONUS...

The large scale mid to upper level flow across the Lower 48 is becoming
increasingly amplified, resulting in slow moving systems affecting the
CONUS.  Along the Mid-Atlantic coast, surface low pressure currently
approximately 120 miles southeast of Cape Hatteras, will be moving slowly
westward across the Outer Banks tonight/early Tuesday and then slowly
north northeastward into southeast Virginia by Wednesday morning.  The
slow movement of the system will support potential for heavy rainfall
amounts across northeast North Carolina into southeast Virginia and the
southern Delmarva Peninsula with two day totals of 2-5" possible.  These
areas have been dry over the past month or two with much of the area in DO
(abnormally dry) drought conditions.

Heavy rains also possible Tuesday into Wednesday across large sections of
the Central to Northern Plains.  A mid to upper level system pushing out
of the Northern Rockies will slow as it emerges into the Northern to
Central Plains Tuesday.  Showers and thunderstorms will increase in
coverage Tuesday across the Central to Northern Plains, with these
showers/thunderstorms continuing into Wednesday and Thursday.  These rains
will bring relief to areas of western Nebraska and southern South Dakota
that are experiencing abnormally dry (D0)to moderate drought (D1)
conditions.  The remainder of the Central to Northern Plains that may
receive heavy rains are not in drought conditions due to greater rains
over the past few months.

Tropical moisture associated with Mario, currently moving northwestward
well off the west coast of the Baja, may being to impact Southern
California Tuesday and Wednesday, before pushing farther north into
Central California mid to late week.  While Mario is forecast to weaken as
it moves northwestward, this tropical moisture may bring showers into far
southern coastal California and the offshore islands Wednesday, with these
showers pushing farther north into much of Southern California on
Thursday. 

Temperature wise across the lower 48, much of the CONUS will see above
average temperatures over the next few days in the last full week of
summer.  Exceptions to this will be in the above mentioned regions where
heavy precipitation is possible, across the Mid-Atlantic Tuesday and
Wednesday, and across the Central to Northern Plains Wednesday into
Thursday where below average temperatures are likely due to this heavy
rain potential.

Oravec

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