Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
300 AM EST Wed Jan 11 2023

Valid 12Z Wed Jan 11 2023 - 12Z Fri Jan 13 2023

...Next Atmospheric River event to impact northern California today,
spreading up the Pacific Northwest coast on Thursday...

...Mountain snows over the central Rockies today as strong/high winds
develop over southern High Plains today...

...Severe thunderstorms possible in the Southeast on Thursday; rain and
some thunderstorms expand up the East Coast Thursday night; heavy snow
possible over northern New England by early Friday...

Following another day of heavy precipitation and gusty winds across
California, the storm system associated with the recent unrelenting series
of atmospheric river events has moved well inland and is currently
bringing mountain snows across the Intermountain West and into much of the
central Rockies.  Meanwhile, an enormous cyclone rotating well off the
West Coast will bring the next round of heavy precipitation and gusty
winds today, this time targeting northern California.  Unlike the recent
atmospheric river events, this upcoming event is forecast to impact areas
farther north from northern California and up the coast of the Pacific
Northwest through the next few days.  The heaviest rains are expected to
impact northwestern California through the next couple of days with a few
inches of rain possible.  By later on Thursday, the threat of heavy rain
will reach the Olympic Peninsula where a few inches of rain is possible as
well.

Meanwhile, the potent weather system associated with yesterday's stormy
weather in California is forecast to emerge into the central Plains today,
and will develop into a strong low pressure system as it pulls in colder
air from the north and warm air from the south.  The system will be
moisture-starved to begin with but moist air from the Gulf of Mexico will
eventually work its way northward into the system.  This will fuel the
development of thunderstorms over the Mid-South by tonight ahead of a
strong cold front as the low pressure system intensifies further and
tracks northeast toward the Mid-Mississippi Valley.  Some of these
thunderstorms could become severe, with high winds and isolated tornadoes
on Thursday across the interior sections of the Southeast.  Showers and 
thunderstorms will then expand in coverage and spread up the Eastern 
Seaboard ahead of a dynamic cold front Thursday night into early on
Friday with locally heavy rain possible.  The low pressure system will be
quite strong by the time it reaches New England early on Friday.  Colder
air to the north of the system will support snow across interior/northern
New England from Thursday night to Friday morning.  The snow could become
heavy as the low pressure center approaches.  Meanwhile, blustery winds
will develop behind the system across the Great Lakes and down into the
Ohio Valley with mixed rain and snow wrapping southward across these areas
toward the spine of the Appalachians.

Across the northern tier, some light snow and wintry mixed precipitation
are expected to accompany a low pressure wave moving slowly across the
upper Midwest into the upper Great Lakes today and into tonight before
merging with the strong low pressure system tracking up across the Ohio
Valley to the lower Great Lakes on Thursday.

Kong


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