273
FXUS01 KWBC 210803
PMDSPD

Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
300 AM EST Fri Nov 21 2025

Valid 12Z Fri Nov 21 2025 - 12Z Sun Nov 23 2025

...Additional heavy rain and flash flooding threat for southern
California, western Arizona and southern Nevada today and
Saturday...

...Record warmth to continue along the Gulf Coast, across the
lower Mississippi Valley and into the Southeast...

...Arctic air to remain absent from the Lower 48 over the next few
days...

An active southern stream of the upper jet will continue over the
next few days, supporting a wet weather pattern from Southern
California, portions of the Desert Southwest, into the central and
southern Plains, mid-Mississippi Valley, Ohio Valley and
Mid-Atlantic.  A low pressure system developing over the central
Plains early this morning continues to support heavy rain and
thunderstorms with threat of flash flooding mainly across the
Arklatex region.  This system will then track steadily eastward
through the eastern U.S. and off the Mid-Atlantic coast Saturday
morning, producing a swath of light to moderate rain stretching
from the central Plains through the Ohio Valley, central
Appalachians and into the Mid-Atlantic today through Saturday
morning.  Portions of the Deep South should also see a round of
thunderstorms into the afternoon today but with a minimal threat
of flash flooding expected.  By Saturday, some widely scattered
showers and storms can be expected across the Southeast into
portions of the Mid-Atlantic.  The entire system including the
trailing cold front will clear the Southeast (except Florida) by
Saturday night.

Meanwhile, across southern California into the Desert Southwest,
two more back-to-back low pressure systems will bring additional
threat of heavy rain and flash flooding  today and Saturday.  The
first low has already spread moderate to locally heavy rain into
much of southern California early this morning.  This lead system
is forecast to quickly weaken as the center reaches the coast near
Los Angeles.  This heavy precipitation will be falling across
areas of southern California and the Southwest that received heavy
rains early in the week and this past weekend, posing further risk
of flash flooding, especially across burn scar and urbanized
regions.  A second system is forecast to develop quickly right on
its heels over the Pacific.  This system could even acquire some
subtropical characteristics under a cold upper low as it heads
toward Baja California Saturday morning.  The farther southward
track of this second system should keep the heaviest rainfall over
Mexico on Saturday.  However by later on Saturday, some bands of
showers and embedded thunderstorms are expected to sweep into
Arizona, reaching into New Mexico by Sunday morning.  Some wet
snow can also be expected over the highest elevations.  Meanwhile,
the Pacific Northwest should see rain arriving early on Sunday
ahead of the next frontal system.

While the southern stream remains active over the next few days,
the northern stream will be characterized by mostly west to east
flow at the mid to upper levels.  This will keep arctic air absent
from the Lower 48 over the next few days.  Most of the Lower 48
will subsequently have above average temperatures late this week
into this weekend.  The exceptions to this will be across central
to southern California into the Southwest where cloud cover and
the likelihood of rains will keep temperatures below average.
Slightly below average temperatures also possible for the
Northeast and New England.  Record warmth will continue for areas
along the Gulf Coast, lower Mississippi Valley and Southeast over
the next two days.  Across these areas both much above average
morning lows and afternoon highs are expected.

Kong/Oravec


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

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