…A western U.S. storm system bringing heavy rain into California and
widespread winter weather impacts across the Intermountain West…
…An impactful heavy rain and flooding event emerges over the Ohio
Valley, Tennessee Valley, and parts of the Appalachians this weekend with
severe thunderstorms across the Deep South…
…Widespread 6 to 10 inches snowfall expected from the upper Midwest
tonight, then through the Great Lakes into New England this weekend with a
swath of sleet/ice just to the south…
…Temperatures will be down to around 5-10 degrees below average across
much of the eastern U.S. followed by a more intense shot of arctic air
into the northern High Plains later this weekend…
A hyperactive weather pattern will bring an expansive low pressure system
across mainland U.S., resulting in widespread impactful weather to
progress from west to east across the country through the next few days.
The widespread heavy rain currently in progress across the lower
elevations of California, and mountain snows that have already overspread
much of the Intermountain West, are the harbingers of things to come for
the rest of the country. The expansive Pacific cyclone responsible for
the widespread inclement weather moving into the western U.S. will
continue to march eastward through the next few days. The heavy rain and
mountain snow impacting California this morning are expected to gradually
taper off later today into this evening when the center of the low
pressure system departs and redevelops over the High Plains.
Meanwhile, the latest surge of arctic air will bring a day of cold and
blustery conditions into the Northeast. But as the arctic high pressure
system quickly slides eastward into the East Coast this evening, moisture
well ahead of the low pressure system from the West will quickly reach the
upper Midwest where an outbreak of snow is anticipated tonight. A colder
surge of arctic air will also enter the northern U.S. this weekend, which
will provide energy for the low pressure system to develop and intensify
over the central Plains. This reinvigorated cyclone will become rather
expansive as it moves across the Ohio Valley Saturday night into Sunday
morning. Widespread 6 to 10 inches of new snow is expected to fall from
the upper Midwest tonight, followed by the Great Lakes into New England
this weekend, along with a swath of sleet/ice just to the south possibly
as far south as the central Appalachians. As the cyclone intensifies
further, the cold front trailing south of the cyclone center will become
quite potent, possibly bringing an outbreak of severe thunderstorms across
the Deep South Saturday night into Sunday morning ahead of the front. The
Storm Prediction Center has a Enhanced Risk from extreme eastern Texas to
western Alabama for the threats of large hail, severe wind gusts, and a
few tornadoes.
In between the wintry weather in the North and the severe weather in the
South, an impactful heavy rain and flooding event is forecast to emerge
over the Ohio Valley, Tennessee Valley, and parts of the Appalachians
during the weekend when the intensifying cyclone interacts with a warm
front coupled with an upper-level jet stream. A Moderate Risk for
Excessive Rainfall is in effect across these regions where rainfall totals
of 3-6 inches are forecast with locally heavier amounts likely in training
convection. Listen to your local officials and local weather forecast
office for more information regarding weather safety.
Much of the West and northern Plains will see below average temperatures,
while the South remains warm with many locations seeing high temperatures
over 80 degrees. The East Coast will be seasonably chilly with highs in
the 30s and 40s. As the next arctic outbreak reaches into the northern
High Plains, below zero temperatures are expected to appear near the
Canadian border this morning before plunging further down into the -20s by
Sunday morning.
Kong
Graphics available at
https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php
