Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
257 PM EST Fri Dec 08 2023

Valid 00Z Sat Dec 09 2023 - 00Z Mon Dec 11 2023

...Heavy snow for the Upper Midwest...

...There is a Slight Risk of excessive rainfall over parts of the Pacific
Northwest on Saturday and over parts of New England on Sunday...

...There is a Slight Risk of severe thunderstorms over parts of the Lower
Mississippi Valley to the Southern Ohio and Tennessee Valleys on
Saturday...

A front extending from the Upper Great Lakes to the Southern High Plains
will slowly move to the Eastern Seaboard by Sunday evening. Showers and
thunderstorms will develop along and ahead of the front over parts of the
Middle/Lower Mississippi Valley and the Tennessee Valley and rain over
parts of the Great Lakes/Ohio Valley on Friday evening into Saturday
morning.

Additionally, heavy snow will develop over the northwest portion of the
storms over parts of the Northern Plains/Upper Mississippi Valley from
Friday evening into Saturday evening. Heavy snow will develop over parts
of the Upper Great Lakes from Saturday evening into Sunday evening.

Moreover, as the boundary moves eastward on Saturday, showers and severe
thunderstorms will develop along parts of the front. Therefore, the SPC
has issued a Slight Risk of severe thunderstorms over parts of the Lower
Mississippi Valley to the Southern Ohio and Tennessee Valleys from
Saturday through Sunday morning. The hazards associated with these
thunderstorms are frequent lightning, severe thunderstorm wind gusts,
hail, and a few tornadoes.

On Sunday, moisture from the Gulf of Mexico will pool along the boundary,
producing heavy rain over parts of the Northeast. Therefore, the WPC
issued a Slight Risk of excessive rainfall over New England on Sunday. The
associated heavy rain will create mainly localized areas of flash
flooding, with urban areas, roads, and small streams the most vulnerable.
In addition, showers and thunderstorms will develop along and ahead of the
front over parts of the Mid-Atlantic to the Southeast and Central Gulf
Coast.

Meanwhile, upper-level energy over the Northern/Central Rockies will
produce snow over parts of the region through Saturday evening. A front
will move onshore over the Pacific Northwest Saturday evening into Sunday.
Ahead of the front, a plume of moisture will stream into the Northwest on
Saturday into Sunday. The moisture streaming inland will produce rain and
high-elevation snow over parts of the Pacific Northwest through Sunday and
snow over the Northern Intermountain Region from Saturday evening into
Sunday. The moisture will also produce heavy rain over parts of the
Northwest on Saturday. Therefore, the WPC has issued a Slight Risk of
excessive rainfall over parts of the Pacific Northwest from Saturday into
Sunday morning. The associated heavy rain will create mainly localized
areas of flash flooding, with urban areas, roads, and small streams the
most vulnerable.


Ziegenfelder


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