Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
354 AM EDT Sun Apr 16 2023

Valid 12Z Sun Apr 16 2023 - 12Z Tue Apr 18 2023

...Heavy snow over the Upper Mississippi Valley/Upper Great on Sunday...

...Temperatures will be 10 to 20 degrees below average over parts of the
Upper Middle Mississippi Valley and the Upper Great Lakes...

...There is a Marginal Risk of excessive rainfall over parts of the Upper
Great Lakes to the Central Appalachians...

On Sunday, an area of low pressure over the Upper Great Lakes/Upper
Mississippi Valley will slowly move northeastward into Canada by Monday
evening. The associated front will move eastward into the
Mid-Atlantic/Southeast by Sunday evening. The system will produce showers
and strong to severe thunderstorms from the Great Lakes to the Central
Appalachians to the southern Mid-Atlantic through Sunday evening. Showers
and thunderstorms will also develop over parts of the Southeast.

Moderate to heavy rain will accompany the rain over the Great Lakes into
the Central Appalachians. Therefore, through Monday morning, the WPC has
issued a Marginal Risk of excessive rainfall over parts of the Great Lakes
into the Central Appalachians. The associated heavy rain will create
localized areas of flash flooding, affecting areas that experience rapid
runoff with heavy rain.

On the northwest side of the storm, heavy snow will develop over parts of
the Upper Mississippi Valley/Upper Great, producing a storm total near 12
inches over parts of the Upper Mississippi Valley and up to 18 inches near
Lake Superior. In addition, along the rain/snowline, pockets of
rain/freezing rain will develop on Sunday. By Monday, the snow will taper
off over parts of the Upper Mississippi Valley while lingering over parts
of the Upper Great Lakes.

Additionally, light to moderate snow will develop over the western
sections of Michigan s Lower Peninsula on Monday. Ironically, these areas
of the Upper Great Lakes and Upper Mississippi Valley just lost their snow
cover.

Furthermore, temperatures will be 10 to 20 degrees below average over
parts of the Upper Middle Mississippi Valley and the Upper Great Lakes
from Sunday into Monday.
Moreover, overnight Sunday rain will develop over parts of the Lower Great
Lakes/Northeast. The rain will linger over parts of the Northeast through
Tuesday morning.

Meanwhile, a front will move onshore over the Pacific Northwest on Sunday
and inland to the Northern Rockies to the Great Basin by Tuesday. The
system will produce coastal rain and highest elevation snow over the
Cascades on Sunday. After the front passes, snow levels will lower over
the Northwest as snow develops over parts of the Northern Intermountain
Region overnight Sunday into Monday. On Monday, coastal rain and higher
elevation snow move into Northern California and snow over parts of the
Sierra Nevada Mountains overnight Monday.


Ziegenfelder


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