Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
331 PM EDT Mon Sep 12 2022

Valid 00Z Tue Sep 13 2022 - 00Z Thu Sep 15 2022

...There is a Slight Risk of excessive rainfall over Southwest and a
second area over the Northeast/northern Mid-Atlantic through Tuesday
morning...

...There is a Slight Risk of excessive rainfall from parts of the Great
Basin/Southwest from Tuesday into Wednesday morning...

Upper-level energy and ample moisture will aid in producing showers and
thunderstorms over the southwestern portion of the country through
Wednesday. The convection will create areas of heavy rain over parts of
the region. Therefore, the WPC has issued a Slight Risk of excessive
rainfall over parts of the Southwest through Tuesday morning. The
associated heavy rain will create mainly localized areas of flash
flooding, with urban areas, roads, and small streams the most vulnerable.

On Tuesday, the upper-level energy moves farther inland over the West, as
does the heavy rain. Therefore, the WPC has issued a Slight Risk of
excessive rainfall over parts of the Great Basin and a smaller second area
over the Southwest from Tuesday into Wednesday morning. The associated
heavy rain will create mainly localized areas of flash flooding, with
urban areas, roads, and small streams the most vulnerable.

Furthermore, as the energy continues to move inland on Wednesday, heavy
rain extends over parts of the Great Basin and Central Rockies. Therefore,
the WPC has issued a Slight Risk of excessive rainfall over parts of the
Great Basin into Central Rockies on Wednesday. The associated heavy rain
will create mainly localized areas of flash flooding, with urban areas,
roads, and small streams the most vulnerable.

Meanwhile, an upper-level low over the Great Lakes/Ohio Valley will move
slowly northeastward to Southeastern Canada by Wednesday. Moisture
streaming over parts of the eastern part of the country will produce rain
and showers/thunderstorms with heavy rain over the eastern third of the
country through Wednesday. Therefore, the WPC has issued a Slight Risk of
excessive rainfall over parts of the Northeast/northern Mid-Atlantic
through Tuesday morning. The associated heavy rain will create mainly
localized areas of flash flooding, with urban areas, roads, and small
streams the most vulnerable.

On Tuesday, the threat of excessive rainfall decreases over parts of the
Northeast. Therefore, the WPC has issued a Marginal Risk of excessive
rainfall over parts of the Northeast 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. On
Wednesday, the threat of excessive rainfall ends over the Northeast.

Moreover, tropical moisture and a lingering weak front over the Southeast
will aid in producing showers and thunderstorms over Florida through
Wednesday. As a result, the WPC has targeted parts of the Florida
Peninsula with a Marginal Risk of excessive rainfall from Monday into
Wednesday. In addition, the associated heavy rain will create localized
areas of flash flooding, affecting areas that experience rapid runoff with
heavy rain. 

Ziegenfelder


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