Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
410 PM EDT Tue Nov 02 2021

Valid 00Z Wed Nov 03 2021 - 00Z Fri Nov 05 2021

...Lake Effect snow accumulations to persist across portions of Michigan
and New York through today; high elevation snow expected in the Central
Rockies through tomorrow..

...Quasi-stationary boundary to bring heavy rain to portions of the
Southern Plains on Wednesday and Thursday before spreading to Florida
Friday...

...First Freeze potential from the Ozarks into the Northeast this week...

Cyclonic flow around a deep low pressure system over eastern Canada is
serving to force cool Canadian air southward over the Great Lakes. When
combined with a shortwave disturbance aloft and completely unfrozen lake
surfaces, this surge of cold air out of the northwest continues to support
favorable conditions for lake effect rain and snow over portions of
Michigan and Upstate New York through Thursday. Scattered Winter Weather
Advisories cover Upper Michigan and Wisconsin through tonight with 2-6" of
snow possible, while the lake effect snow threat will linger over Western
Pennsylvania and New York through tomorrow morning with localized
accumulations up to 3-5". Further West, shortwave trough activity coupled
with a stationary front banked up along the Central Rockies elevations
will focus both rain and snow chances in North Central-Colorado. Unlike
its eastern counterpart, moderate to heavy snow accumulations in this part
of the country will be relegated to higher elevations above 8500 ft, where
total snow accumulations of 5-10 inches (with locally higher
accumulations) remain possible through tomorrow morning.

In the neighboring Southern Plains, the southern edge of the
aforementioned stationary front is forecast to bring showers and
thunderstorms to much of the region through Thursday morning. The front is
expected to slowly meander south through South-Central Texas this week,
delivering moderate to heavy rainfall to the eastern portion of the state.
With rainfall totals of 1-3" in 24 hours possible in some areas, the
Weather Prediction Center has issued a Marginal Risk of Excessive Rainfall
for portions of Southeast Texas effective Wednesday morning through
Thursday morning, where isolated flash flooding may occur. Meanwhile, a
series of low pressure systems approaching the Pacific Northwest will
bring light rain and high elevation snow to the region throughout the
period, but no hazardous weather is currently anticipated.

Temperature-wise, unseasonably cool weather is expected to persist
throughout the Central and Eastern US as surface high pressure dominates
and draws cold air south. The greatest hit to daily maximum temperatures
will be felt in the Central and Southern Plains where highs are forecast
to sit 20 to 25 degrees below normal as they struggle to escape the 40s
and 50s. Moreover, the anomalously cool airmass in place will support
sub-freezing night-time low temperatures from the Ozarks eastward to the
Northeast through midweek, which may damage sensitive crops and other
outdoor vegetation. Accordingly, a swath of Freeze Warning, Watches, and
Frost Advisories extend from Northwest Arkansas into New England. In stark
contrast to the cold spell to the east, temperatures from the Rockies to
the West Coast are forecast to remain around average on Tuesday before
warming up on Wednesday. Thanks to a building upper-level ridge, high
temperatures across these regions are expected to rise to 5 to 10 degrees
above average. 

Asherman/Zavadoff

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