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103
FXUS01 KWBC 221818
PMDSPD

Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
118 PM EST Fri Nov 22 2024

Valid 00Z Sat Nov 23 2024 - 00Z Mon Nov 25 2024

...Very strong Atmospheric River is starting to press south
producing one last round of heavy rain/mountain snows and strong
wind gusts across portions of central California into tonight...

...Moderate to heavy snow for portions of the Central Appalachians
today; while lighter snows linger across Northeast Interior New
England through Saturday night...

...Elevated Fire Weather conditions exist across northern
Peninsular Florida today...

...Some possible Frost/Freeze conditions across the South
tonight...

...Above average temperatures expand across the Central U.S. this
weekend...


Regional RADAR mosaic and GOES Satellite suite show the second
strong surface cyclone lifting north off the Pacific Northwest
coast.  Stronger flow aloft has allowed the cold front to finally
make an onshore push and direct the anomalously strong Atmospheric
River to direct away from saturated/flooded areas of Northern
California providing beneficial rainfall across Central California
into the Central Sierra Nevada range where it will continue to
produce heavy mountain snows tonight into very early morning
Saturday.  Multiple feet of snow is likely to accumulate generally
at or above 7000`.   Very strong/gusty winds will slowly diminish
through the rest of the day today, behind the front into the
Pacific Northwest.  Given saturated grounds, tree-falls remain
possible and may result in additional power outages.   Onshore
flow will continue through the weekend with scattered lighter
showers, mountain snows (reducing in elevation with cold air
filtering in) and reducing winds.

A very strong core of an upper-level closed low over the Northeast
has supported a strong surface low with enhanced winds as it is
swinging back around from Upstate New York through Northeast PA
before transferring to a developing surface near Georges Bank
toward Nova Scotia.  The strength of the winds and wrapped around
moisture is also enhancing upslope flow out of the Ohio Valley
providing another opportunity for moderate to heavy snows across
the Central Appalachians for a few more hours as the storm moves
away.  Additional 5-9" snow is accompanied by high winds that a
Blizzard Warning is in effect until 6pm this evening for portions
of eastern WV.  Winter storm warnings and advisories extend into
portions of central and northeast PA and southern and southeast
Upstate NY through the evening as well.  By the weekend, the
secondary low near Nova Scotia will take full control and
generally stall, throwing moisture and change for light lingering
snow and rain showers through Interior northeast New England
through the weekend.

Along the periphery of this storm, strong winds and dry conditions
have resulted in an area of Elevated Fire Weather (level 1 of 3)
to be issued across the northern neck of Peninsular Florida for
the remainder of the day.  Also, behind the front, the higher
winds are bringing sufficiently cold air south that weather
service offices in Mississippi and Alabama to issue Frost and
Freeze Warnings.

With the Atmospheric River and stronger westerly flow aloft across
the Rockies, will bring downsloping winds and broad return flow
around the High Pressure across the Southeast/Northeast Gulf of
Mexico by the weekend.  This will bring solid warming across the
Southern and Central Plains through the weekend with High
temperatures in the 70s and 80s in the south and 50s and 60s
across the the Lower Missouri River and Western Midwest
states...generally 5-15 degrees above normal. A record or two may
be broken.  Though another surge of colder Arctic air is starting
to nose into the High Plains of N MT by Sunday (20-30 degrees
below normal).


Gallina


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