Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
250 AM EST Mon Dec 06 2021

Valid 12Z Mon Dec 06 2021 - 12Z Wed Dec 08 2021

...Gusty winds and lake effect snow to impact the Great Lakes and Interior
Northeast through early Tuesday...

...Strong to severe thunderstorms and heavy rain possible today across
portions of the Southeast and Lower Mississippi Valley...

A vigorous low pressure system currently located over the Upper Great
Lakes will exit the U.S. and enter southeast Canada by this afternoon.
Light-to-moderate snow on the backside of the system will turn into mostly
lake effect showers by this evening as bitterly cold air rushes over the
ice-free Great Lakes. Several additional inches of snow are likely for
localized areas that typically see impacts from lake effect snow. The
arctic airmass over the Northern Plains and Upper Midwest will definitely
make extra layers necessary if venturing outdoors. Low temperatures below
zero and highs only into the single digits are forecast throughout
northern Montana, North Dakota, and northern Minnesota until Wednesday.
Gusty winds will make it feel even colder. In fact, Wind Chill Advisories
are in effect here to highlight the potential for wind chills to dip as
low as 30 below zero. Speaking of wind gusts, portions of the Interior
Northeast will also be dealing with potentially damaging winds as a potent
cold front pushes through this evening along with scattered showers. High
Wind Warnings and Wind Advisories have been issued from far northern
Pennsylvania to northern Vermont, where winds could gust over 50 mph.
Outside of the aforementioned lake effect snow, Tuesday should be a much
quieter day throughout these regions.

Farther south, the aforementioned cold front extends to the Southern
Plains and is expected to continue racing southeastward until stalling
along the Gulf Coast on Tuesday. A line of showers and thunderstorms
riding this cold front could spawn a few damaging wind gusts and isolated
tornadoes between Alabama and eastern Texas today. The Storm Prediction
Center has issued a Slight Risk (level 2/5) of severe weather that
includes central Mississippi, northern Louisiana, and far eastern Texas.
Additionally, heavy rain and a few isolated instances of flooding cannot
be ruled out as well.

By Tuesday night, an approaching upper-level trough is forecast to enter
the Ohio Valley while an area of low pressure begins to develop along the
Carolina coast. As a result, an area of light snow is expected to stretch
from the Ohio Valley to the Mid-Atlantic into Wednesday morning. There
remains large uncertainty regarding where exactly light snow will fall,
but morning commutes may be impacted nonetheless as this would be the
first accumulating snowfall for many.

For the western U.S., periods of light coastal/lower elevation rain and
mountain snow are forecast to overspread much of the Northwest and
Northern Rockies today before moisture reaches the Central Rockies and
parts of central California on Tuesday. The next cold front is set to
sweep into the Northwest on Tuesday night and produce more rounds of
mostly light precipitation, with heavier snowfall confined to the far
northern Washington Cascades.

Snell

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