Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
429 PM EDT Sat Jun 17 2023

Valid 00Z Sun Jun 18 2023 - 00Z Tue Jun 20 2023

...There is a Slight Risk of excessive rainfall over parts of Northern New
England and the Southeast on Saturday and generally over the southeastern
parts of the country from Sunday into Monday evening...

...There is an Enhanced Risk of severe thunderstorms over parts of
Central/Southern Plains on Saturday and Lower Mississippi and Tennessee
Valleys/Southeast on Sunday...

...Excessive Heat Warnings and Heat Advisories over the Central and
Western Gulf Coast...

An upper-level low over the Northeast slowly drifts into Southeastern
Canada by Monday. The system will produce rain with embedded
thunderstorms, creating heavy rain over parts of the Northeast. Therefore,
the WPC has issued a Slight Risk of excessive rainfall over parts of
Northern New England through Sunday morning. The associated heavy rain
will create mainly localized areas of flash flooding, with urban areas,
roads, and small streams the most vulnerable. The excessive rain threat
ends on Sunday.

A weak front along the Gulf Coast and tropical moisture will also produce
showers and thunderstorms with heavy rain over parts of the Central
Florida Peninsula. Therefore, the WPC has issued a Slight Risk of
excessive rainfall over parts of the Central Florida Peninsula through
Sunday morning. The associated heavy rain will create mainly localized
areas of flash flooding, with urban areas, roads, and small streams the
most vulnerable. The excessive rain moves westward on Sunday.

Moreover, fronts and a dryline across Texas and Oklahoma will create
showers and severe thunderstorms over the area. Therefore, the SPC has
issued an Enhanced Risk of severe thunderstorms over parts of the
Central/Southern Plains through Sunday morning.

The hazards associated with these thunderstorms are frequent lightning,
severe thunderstorm wind gusts, hail, and a few tornadoes. Furthermore,
there is an increased threat of hail two inches or greater and severe
thunderstorm wind gusts of 65 knots or greater over the area. In addition,
the threat of severe thunderstorms extends southeastward into the Central
Gulf Coast and the Southeast through Sunday morning.

On Sunday, the fronts consolidate and move eastward over eastern Texas and
Louisiana, producing showers and thunderstorms with heavy rain. Therefore,
the WPC has issued a Slight Risk of excessive rainfall over parts of the
Middle/Lower Mississippi Valley, Tennessee Valley, Central Gulf Coast, and
Southeast from Sunday into Monday morning. The associated heavy rain will
create mainly localized areas of flash flooding, with urban areas, roads,
and small streams the most vulnerable.

Further, the boundary will produce showers and severe thunderstorms over
parts of the Lower Mississippi Valley, Tennessee Valley, Central Gulf
Coast, and Southeast. Therefore, the SPC has issued an Enhanced Risk of
severe thunderstorms over parts of the Lower Mississippi Valley, Tennessee
Valley, and Central Gulf Coast from Sunday into Monday morning.
Furthermore, there is an increased threat of severe thunderstorm wind
gusts of 65 knots or greater over the area.

On Monday, the threat of excessive rainfall moves eastward to the
southeastern parts of the country. Therefore, the WPC has issued a Slight
Risk of excessive rainfall over parts of the Southeast, southern
Mid-Atlantic, and Southern Appalachians on Monday. The associated heavy
rain will create mainly localized areas of flash flooding, with urban
areas, roads, and small streams the most vulnerable. The threat of severe
thunderstorms also decrees to a Marginal Risk over the region.

Furthermore, upper-level ridging, high temperatures, and temperatures not
cooling off overnight much have contributed to Excessive Heat Warnings and
Heat Advisories over the Central and Western Gulf Coast.

Elsewhere, a deep upper-level low will move over the Northwest, creating
scattered rain showers over parts of the Northwest into the Northern
Rockies from Saturday evening into Monday.



Ziegenfelder





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