Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
253 AM EST Thu Dec 01 2022

Valid 12Z Thu Dec 01 2022 - 12Z Sat Dec 03 2022

...Heavy snow for parts of the Northern/Central Rockies and the Sierra
Nevada Mountains on Thursday...

...Lake-effect snow downwind from Lakes Erie and Ontario on Thursday...

...There is a Marginal Risk of excessive rainfall for parts of the
California Coast and Pacific Northwest on Friday into Saturday morning...

On Thursday, a front over the Pacific Northwest and Northern California
will move eastward to the Great Lakes to Southern High Plains by Saturday.
The system will produce snow over parts of the Pacific Northwest/Great
Basin and heavy snow over parts of the Northern/Central Rockies and the
Sierra Nevada Mountains. The snow will result in reduced visibility and
hazardous driving conditions.

In addition, moisture will stream onshore over parts of Central/Southern
California, producing moderate to heavy rain over the region. Therefore,
the WPC has issued a Marginal Risk of excessive rainfall over parts of the
Central/Southern California Coast through Friday morning.

The associated heavy rain will create localized areas of flash flooding,
affecting areas that experience rapid runoff and burn scars.

On Friday, the snow will end over most of the Northwest, California, and
the Great Basin. However, more moisture moves into the Pacific Northwest
and parts of Northern California as snow returns to the Olympic Peninsula
and parts of the Northern Cascades into Saturday morning. The snow will
result in reduced visibility and hazardous driving conditions.

Moreover, the plume of moisture will produce moderate to heavy rain over
parts of the Pacific Northwest Coast into Northern California. Therefore,
the WPC has issued a Marginal Risk of excessive rainfall over parts of the
Pacific Northwest Coast into Northern California Coast from Friday through
Saturday morning. The associated heavy rain will create localized areas of
flash flooding, affecting areas that experience rapid runoff and burn
scars.

Furthermore, a plume of moisture continues over parts of Southern
California, producing moderate to heavy rain. Therefore, the WPC has
issued a Marginal Risk of excessive rainfall over parts of the Southern
California Coast from Friday through Saturday morning. The associated
heavy rain will create localized areas of flash flooding, affecting areas
that experience rapid runoff and burn scars.

Also, on Thursday, upper-level energy moving over the Lower Great Lakes
into the Northeast will aid in triggering lake-effect snow downwind from
Lakes Erie and Ontario. The snow has prompted Lake-Effect Snow Warnings
and Winter Weather Advisories over the impacted areas. The snow will
result in reduced visibility and hazardous driving conditions.

Meanwhile, as the storm moves out of the Rockies, snow develops over parts
of the Northern Plains on Friday. Overnight Friday, the snow moves into
the Upper Mississippi Valley and the Upper Great Lakes. The snow will
result in reduced visibility and hazardous driving conditions.

Overnight Thursday, moisture starts to move northward over the Southern
Plains into the Upper Midwest. On Thursday night, rain with embedded
thunderstorms develops over parts of the Western Gulf Coast, moving into
parts of the Lower Mississippi Valley on Friday. Overnight Friday, rain
also develops over parts of the Lower/Middle Mississippi Valley and the
Ohio Valley/Great Lakes, which expands into parts of the
Northeast/Mid-Atlantic by Saturday morning. In addition, the rain changes
over to snow over parts of the Western Ohio Valley and Great Lakes. 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