Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
352 PM EDT Sun Sep 15 2024

Valid 00Z Mon Sep 16 2024 - 00Z Wed Sep 18 2024

...There is a Slight Risk of excessive rainfall over parts of the Lower
Mississippi Valley and Southeast on Sunday and the southern Mid-Atlantic
on Monday...

...Upper-level low will bring unsettled weather and well below average
temperatures to the West with high-elevation wet snow in the Sierra Nevada
Mountains...

Upper-level energy over the Lower Mississippi Valley will produce rain and
thunderstorms over parts of the Lower Mississippi Valley and Southeast,
with heavy rain over parts of the region. Therefore, the WPC has issued a
Slight Risk (level 2/4) of excessive rainfall over parts of the Lower
Mississippi Valley and Southeast through Monday morning. The associated
heavy rain will create mainly localized areas of flash flooding, with
urban areas, roads, small streams, and low-lying areas the most vulnerable.

On Monday, low pressure along the Southeast Coast will pull moisture off
the Atlantic, producing showers and thunderstorms over the Mid-Atlantic.
The moisture will aid in creating heavy rain over parts of the southern
Mid-Atlantic. Therefore, the WPC has issued a Slight Risk (level 2/4) of
excessive rainfall over parts of the southern Mid-Atlantic from Monday
into Tuesday morning. The associated heavy rain will create mainly
localized areas of flash flooding, with urban areas, roads, small streams,
and low-lying areas the most vulnerable.

On Tuesday, the moisture will continue to move inland off the Atlantic.
Showers and thunderstorms will develop over the Mid-Atlantic, producing
moderate to heavy rain. Therefore, the WPC has issued a Marginal Risk
(level 1/4) of excessive rainfall over parts of the Mid-Atlantic on
Tuesday.  The associated heavy rain will create localized areas of flash
flooding, affecting areas that experience rapid runoff with heavy rain.

Meanwhile, a developing upper-level low over California will slowly move
to the Northern Intermountain region by Tuesday evening. The system will
produce rain with embedded thunderstorms over parts of California, the
Pacific Northwest, and the Great Basin. On Monday, over the highest
elevations of the Sierra Nevada Mountains, wet snow will develop, while
rain with embedded thunderstorms will continue over parts of California,
the Pacific Northwest, and the Great Basin through Tuesday.

On Monday, as the upper-level low moves farther inland, showers and strong
to severe thunderstorms will develop over parts of the Eastern Great
Basin, Central Rockies, and Southern Rockies. Therefore, the SPC has
issued a Marginal Risk (level 1/5)of severe thunderstorms over parts of
the Eastern Great Basin, Central Rockies, and Southern Rockies from Monday
into Tuesday morning. The hazards associated with these thunderstorms are
frequent lightning, severe thunderstorm wind gusts, hail, and a minimal
threat of tornadoes.

On Tuesday, as the upper-level low moves into the Northern Intermountain
Region, the threat of severe thunderstorms moves to the High Plains.
Therefore, the SPC has issued a Marginal Risk (level 1/5) of severe
thunderstorms over parts of the Northern High Plains, Central High Plains,
and Southern High Plains. The hazards associated with these thunderstorms
are frequent lightning, severe thunderstorm wind gusts, hail, and a
minimal threat of tornadoes.


Ziegenfelder


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