Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
300 PM EST Wed Dec 08 2021

Valid 00Z Thu Dec 09 2021 - 00Z Sat Dec 11 2021

...Developing winter storm will produce the first widespread and
significant snow of the season across parts of the Sierra Nevada,
Intermountain West, Central Rockies, and Central Plains through Friday...

...Slight Risk of Severe Weather for parts of the
Mississippi/Tennessee/Ohio Valleys on Friday into Friday night...

...Light snow possible across the Northeast tonight and Upper Great Lakes
on Thursday...

...Potentially record-breaking warm temperatures to build across the
south-central and eastern United States...

The main weather story for the latter part of the week will be a
developing winter storm that is expected to impact much of the western
mountain ranges and central U.S.. Short-wave energy, currently way out in
the Pacific, will amplify and phase with a southern stream system as it
enters the CONUS Thursday morning. The strengthening of the upper-trough
will lead to the development of a surface wave over the Intermountain
West. This developing system will produce a swath of 8-12 inches of snow
extending from the Sierra Nevada, through the Intermountain West and into
the Central Rockies. Locally higher amounts are likely over the highest
elevations of Utah and the northern Colorado Rockies. Meanwhile light snow
will fall over parts of the Northeast and Great Lakes tomorrow behind one
system departing into the Canadian Maritime and another moving across
central Canada. Additional snow will fall over the Central Rockies and
Utah highlands on Friday as the surface low begins to deepen and ramp up
over Central Plains. Between 2-3 feet of snow is likely over much of the
Central Rockies by Saturday morning. A swath of snow, on the magnitude of
4-8 inches, will develop in the cold sector of this system from the Front
Range across the Central Plains and into the Upper Mississippi Valley on
Friday. Light snow continues for the Cascades on Friday as well. Scattered
thunderstorms are expected to overspread much of the Deep South on Friday
as the deepening system develops into a dynamic mid-latitude cyclone and
begins to tap into rich moisture from the Gulf of Mexico. Severe
Thunderstorms are possible Friday into Friday night across parts of the
Lower/Middle Mississippi Valley and the Tennessee/Ohio Valleys due to
increased instability caused by this storm. Heavy snowfall is forecast to
spread into the Upper Midwest/Great Lakes by Friday evening.

The approaching winter storm will generate a strong plume of warm moist
air into the

Kebede

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