Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
1125 PM EST Wed Feb 22 2023

Valid 12Z Thu Feb 23 2023 - 12Z Sat Feb 25 2023

...Significant coast-to-coast winter storm will continue to produce
widespread heavy snow across portions of California...

...A swath of heavy snow and locally significant ice will stretch from the
Great Lakes to the Northeast...

...Record-breaking warmth expected over the East going through Thursday as
extreme cold hits the Northern Plains and the Intermountain West...

A prolonged major winter storm will continue to bring widespread heavy
snow and blizzard conditions to portions of the West as well as the
northern Plains/Great Lakes into Thursday as a series of low pressure
waves traverse a front to the south.  Heavy snowfall rates of as much as 1
to 2 inches/hour are expected to combine with winds locally as high as 40
to 50 mph to drive significant impacts that will include major disruptions
to travel, infrastructure, livestock and recreation. This series of low
pressure waves that will make up this coast-to-coast winter storm will
bring heavy snow and locally significant ice from the Great Lakes into the
Northeast, and many of these areas are expected to see an additional 6 to
12 inches of snow, with some amounts perhaps as high as 18 inches. Power
outages and areas of tree damage will be possible across these areas, and
especially for the locations seeing a combination of stronger winds and
accumulating ice.

On Thursday and Friday, the heavy snowfall threat across the West should
become more centered over California as a new storm system developing just
off the West Coast drops south and begins to edge into the Southwest for
the end of the week.  Multiple rounds of new snowfall should accumulate to
as much as 3 to 5 feet for the Sierra Nevada, with locally heavier totals
for the highest peaks. Lesser amounts of 1 to 2 feet are forecast
elsewhere across portions of the Great Basin and into the Four Corners
region. Given the depth of cold air that has infiltrated the West,
accumulating snow will also be expected over some of the lower foothills
and interior valley areas near the Pacific Coast adjacent to the terrain
where snowfall is less common.

Extremely cold air will continue across many areas of the West and
stretching out across the northern High Plains and the upper Midwest
through Thursday with the proximity of deep Arctic air. Temperatures will
locally be as much as 30 to 40 degrees below average, with many locations
especially over the northern High Plains seeing temperatures well below
zero.  On the warm side of the aforementioned Arctic front and  evolving
winter storm, record-setting warmth is expected with temperatures on
Thursday forecast to be as much as 30 to 40 degrees above normal. In fact,
many areas of the Ohio Valley, the Mid-South, Gulf Coast, Southeast, and
southern Mid-Atlantic will see temperatures pushing 80 degrees for
afternoon highs which would approach, and potentially exceed, monthly
records for February.

Roth

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