Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
258 AM EST Wed Nov 30 2022

Valid 12Z Wed Nov 30 2022 - 12Z Fri Dec 02 2022

...Heavy snow for parts of the Cascades/Northern Rockies and the Sierra
Nevada Mountains...

...Lake-effect snow downwind from the Great Lakes...

...There is a Slight Risk of severe thunderstorms and a Marginal Risk of
excessive rainfall for parts of the Eastern Gulf Coast/Southeast...

On Wednesday, a front extending from the Lower Great Lakes to the Central
Gulf Coast will move eastward off the East Coast overnight. As a result,
showers and severe thunderstorms will develop over the Eastern Gulf
Coast/Southeast. Therefore, the SPC has issued a Slight Risk of severe
thunderstorms over parts of the Eastern Gulf Coast/Southeast through
Thursday morning. The hazards associated with these thunderstorms are
frequent lightning, severe thunderstorm wind gusts, a few tornadoes, and a
minimal threat of hail.

Moreover, there will be heavy rain associated with these thunderstorms.
Therefore, the WPC has issued a Slight Risk of excessive rainfall over
parts of the Eastern Gulf Coast/Southeast through Thursday morning. The
associated heavy rain will create mainly localized areas of flash
flooding, with urban areas, roads, and small streams the most vulnerable.
On Thursday, the threat of severe thunderstorms and excessive rainfall
ends over the Southeast.

In addition, rain will develop over parts of the Ohio Valley, Lower Great
Lakes, Central Appalachians, and the Mid-Atlantic that will move eastward
into the Northeast by Wednesday afternoon and end overnight Wednesday.
Furthermore, the rain will change over to snow along the western edge of
the precipitation shield as the rain moves eastward. In the wake of the
system, lake-effect snow will develop downwind from Lakes Superior, Erie,
and Ontario. However, the heaviest snow for Lake Michigan will be over the
northern half of the Lower Peninsula of Michigan and much lighter over the
southern part of western Michigan. On Thursday, the lake-effect snow will
continue for areas downwind from Lake Ontario. The snow will result in
reduced visibility and hazardous driving conditions.

Meanwhile, on Wednesday, a front will move onshore over the Pacific
Northwest and move eastward to the Northern/Central Rockies by Friday.
Moisture will also move onshore, producing coastal rain and
higher-elevation snow over the Pacific Northwest into the Northern
Intermountain Region. Heavy snow will develop over parts of the Southern
Cascades, Northern California, and parts of the Northern Intermountain
Region on Wednesday. The snow has prompted Winter Storm Warnings for the
Cascades, Northern Intermountain Region, and Northern/Central California.
The snow levels will lower to near the coast over the Olympic Peninsula.

Furthermore, the snow levels will lower over Northern California overnight
Wednesday into Thursday. On Thursday, heavy snow will develop over the
Sierra Nevada Mountains and parts of the Northern Rockies. By Friday
morning, the snow and rain will start to weaken over the West Coast. The
snow will result in reduced visibility and hazardous driving conditions.


Ziegenfelder


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