Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
329 AM EDT Mon Sep 04 2023

Valid 12Z Mon Sep 04 2023 - 12Z Wed Sep 06 2023

...There is a Slight Risk of excessive rainfall over the parts of the
Northern Rockies/Northern High Plains on Monday...

...There is a Slight Risk of severe thunderstorms over parts of the
Northern/Central High Plains...

...There are Heat Advisories over parts of the Upper Mississippi Valley
and Northeast on Monday...

A front over the Northern Rockies/Northern High Plains will move to the
Mississippi Valley by Wednesday. The system will create showers and
thunderstorms with heavy rain over parts of southern Montana, northern
Wyoming, southwestern North Dakota, and northwestern North Dakota.
Therefore, the WPC has issued a Slight Risk of excessive rainfall with
these thunderstorms over parts of the Northern Rockies/Northern High
Plains through Tuesday morning. The associated heavy rain will create
mainly localized areas of flash flooding, with urban areas, roads, small
streams, narrow crayons/gullies, and burn scars the most vulnerable.

Furthermore, the front will produce showers and severe thunderstorms over
parts of northeastern Wyoming, southern North Dakota, and northwestern
North Dakota. Therefore, the SPC has issued a Slight Risk of severe
thunderstorms over parts of the Northern Plains through Tuesday morning. 
The hazards associated with these thunderstorms are frequent lightning,
severe thunderstorm wind gusts, hail, and a minimal threat of tornadoes.

On Tuesday, the threat of excessive rainfall decreases slightly over the
Upper Midwest. As the front moves eastward, showers and thunderstorms with
moderate to heavy rain will develop over parts of northern South Dakota, a
large portion of North Dakota, northern Minnesota, and northwestern
Wisconsin. Therefore, the WPC has issued a Marginal Risk of excessive
rainfall over parts of the Northern Plains and Upper Mississippi Valley
from Tuesday into Wednesday morning.  The associated heavy rain will
create localized areas of flash flooding, affecting areas that experience
rapid runoff with heavy rain.

However, the threat of severe thunderstorms continues as the front
produces showers and severe thunderstorms over north-central Iowa,
southeastern Minnesota, and northwestern Wisconsin. Therefore, the SPC has
issued a Slight Risk of severe thunderstorms over the Upper Mississippi
Valley Tuesday into Wednesday morning.

The hazards associated with these thunderstorms are frequent lightning,
severe thunderstorm wind gusts, hail, and a few tornadoes. In addition, by
Wednesday morning, showers and thunderstorms will extend from the Upper
Mississippi Valley, Great Lakes, and Ohio Valley to the Middle Mississippi
Valley and the Southern Plains.

Meanwhile, upper-level energy over the Southern Plains will aid in
creating showers and thunderstorms over parts of the Lower Mississippi
Valley and Western Gulf Coast on Monday into Tuesday evening.

Furthermore, upper-level ridging over the Upper Mississippi Valley, Great
Lakes, and Ohio Valley will promote hot temperatures, prompting Heat
Advisories over the Upper Mississippi Valley on Monday. Heat Advisories
also creep into the Northeast as part of the upper-level ridge creeps into
the Northeast. Hot temperatures will also be over the Mid-Atlantic on
Monday. On Tuesday, the upper-level ridging will move over the
Northeast/Mid-Atlantic, allowing hot temperatures to continue over the
area.


Ziegenfelder


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