Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
353 AM EDT Fri Jul 28 2023

Valid 12Z Fri Jul 28 2023 - 12Z Sun Jul 30 2023

...There is a Slight Risk of excessive rainfall over parts of the Great
Lakes/Ohio Valley on Friday and over the Central Appalachians on
Saturday...

...There is an Enhanced Risk of severe thunderstorms over parts of the
Great Lakes/Ohio Valley westward to the Middle Missouri Valley...

...Excessive Heat Warnings and Advisories from parts of Central/Southern
Plains eastward to the Northeast/Mid-Atlantic and smaller areas over
portions of California, Southwest, and the Southern Rockies...

A front extending from the Great Lakes westward to the Northern
Intermountain Region will slowly move southward to the Mid-Atlantic
westward to the Central High Plains, will produce showers and severe
thunderstorms over parts of the Great Lakes/Ohio Valley westward to the
Middle Missouri Valley. Therefore, the SPC has issued an Enhanced Risk of
severe thunderstorms over parts of the Great Lakes/Ohio Valley westward to
the Middle Missouri Valley through Saturday morning. The hazards
associated with these thunderstorms are frequent lightning, severe
thunderstorm wind gusts, hail, and a minimal threat of tornadoes.
Additionally, there is a threat of hail two inches or greater over parts
of the Middle Missouri Valley.

Further, the showers and thunderstorms will also produce heavy rain over
parts of the Great Lakes/Ohio Valley. Therefore, the WPC has issued a
Slight Risk of excessive rainfall over parts of the Great Lakes/Ohio
Valley through Saturday morning. The associated heavy rain will create
mainly localized areas of flash flooding, with urban areas, roads, and
small streams the most vulnerable.

On Saturday, showers and severe thunderstorms will develop over two
regions along the boundary as the front moves southward. Therefore, the
SPC has issued a Slight Risk of severe thunderstorms over parts of
Southern New England to the Mid-Atlantic and Central Appalachians from
Saturday through Sunday morning. The hazards associated with these
thunderstorms are frequent lightning, severe thunderstorm wind gusts,
hail, and a few tornadoes.

Furthermore, the showers and thunderstorms will create areas of heavy rain
over parts of West Virginia, far eastern Kentucky, southwestern Virginia,
and northeastern Tennessee. Therefore, the WPC has issued a Slight Risk of
excessive rainfall over parts of the Central/Southern Appalachians. The
associated heavy rain will create mainly localized areas of flash
flooding, with urban areas, roads, and small streams the most vulnerable.

The second area of showers and severe thunderstorms will develop over the
western portion of the front over eastern Wyoming, southwestern South
Dakota, and western Nebraska. Therefore, the SPC has issued a Slight Risk
of severe thunderstorms over parts of the Northern/Central High Plains
from Saturday through Sunday morning. The hazards associated with these
thunderstorms are frequent lightning, severe thunderstorm wind gusts,
hail, and a few tornadoes.

Meanwhile, upper-level energy and tropical moisture will produce showers
and thunderstorms over parts of the Southeast through Sunday. In addition,
upper-level energy and moisture will create showers and thunderstorms over
parts of the Southwest into the Central/Southern Rockies from the late
afternoon into the late evening on Friday and Saturday.

Moreover, an upper-level high over the Southwest to the Southern Plains
will expand eastward into the Middle/Lower Mississippi Valley and the
Ohio/Tennessee Valleys and upper-level ridging will expand westward over
the Mid-Atlantic will bring hot high temperatures and hot low temperatures
that will contribute to areas not cooling off overnight, which have
contributed to Excessive Heat Warnings and Heat Advisories over portions
of the Central/Southern Plains eastward to the Northeast/Mid-Atlantic. In
addition, moisture moving into the Southwestern portion of the country has
reduced the areal coverage of the Excessive Heat Warnings and Heat
Advisories to the southernmost counties of California and parts of
Southern Arizona.

Additionally, the dangerous heat will engulf much of the eastern half of
the U.S. Some locations in the Northeast and Mid-Atlantic can expect their
hottest temperatures so far in 2023. Further, portions of northeast
Kansas, northern and central Missouri, and southern Illinois, including
St. Louis and Kansas City, may see overnight temperatures remain above 80
degrees Friday and Saturday. The dangerous heat peaks in the Northeast,
Mid-Atlantic, and Midwest Friday and Saturday before a cold front provide
these regions with a welcomed return of cooler and more comfortable
temperatures Sunday and early next week.

Ziegenfelder


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