Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
253 PM EST Sat Dec 17 2022

Valid 00Z Sun Dec 18 2022 - 00Z Tue Dec 20 2022

...Heavy snow over northern Maine...

...Lake-effect snow downwind from Great Lakes with the highest snowfall
totals downwind from Lakes Erie and Ontario...

...Temperatures will be 20 to 35 degrees below average over the Northern
High Plains...

Upper-level energy over the Great Lakes slowly moves eastward to the
Northeast by Monday. The energy and cold air passing over the ice-free
Lakes will produce lake-effect snow downwind from the Great Lakes through
Monday. The lake-effect snow will be the heaviest downwind from Lakes
Ontario and Erie. Winter Weather Advisories are over parts of Minnesota,
Wisconsin, and Michigan, with Lake-Effect Snow Warnings downwind from
Lakes Ontario and Erie. In addition, low pressure offshore of Maine will
produce heavy snow at times over northern Maine through Monday. Moreover,
light snow will develop over parts of the Ohio Valley and the Central
Appalachians on Saturday evening into Sunday.

Meanwhile, weak onshore flow will aid in producing coastal rain and higher
elevation snow over parts of the Pacific Northwest through Monday, with
light rain/freezing rain impacting the foothills of the Cascades on
Saturday night into Sunday. Farther inland, snow will develop over parts
of the Northern Intermountain Region, likewise through Monday.

Furthermore, very cold high pressure over Alaska and Northwestern Canada
will stream very cold air out of West-Central Canada into the Northern
High Plains/Northern Plains that will be 20 to 35 degrees below average.

On Sunday, moisture from the Western Gulf of Mexico will start to stream
northward over the Southern Plains. As a result, the atmosphere will
slowly moisten, producing scatted showers and thunderstorms over the
Western and Central Gulf Coast on Monday. Additionally, the moisture will
interact with the cold air moving southward over the Plains producing a
wave of low pressure over the Central Plains Sunday night into Monday. The
system will produce light snow over parts of the Northern/Central Plains
and the Upper/Middle Mississippi Valley Sunday night into Monday.
Elsewhere, a lingering front over the southern parts of Florida will
produce scattered showers and thunderstorms over the Florida Peninsula
through Monday morning.


Ziegenfelder


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