Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
401 AM EDT Tue Jun 27 2023

Valid 12Z Tue Jun 27 2023 - 12Z Thu Jun 29 2023

...There is a Slight Risk of excessive rainfall over parts of the Northern
Mid-Atlantic...

...There is an Enhanced Risk of severe thunderstorms over parts of the
Central/Southern Plains on Tuesday and two areas of Slight Risk on
Wednesday over parts of Upper Mississippi Valley and Lower Mississippi
Valley...

...Excessive Heat Warnings and Advisories over parts of the Southwest,
Southern Plains, Lower Mississippi Valley, Central/Western Gulf Coast...

...Air Quality alerts over parts of the Upper Mississippi Valley, Great
Lakes, and Ohio Valley...

A front extending from parts of the Great Lakes/Mid-Atlantic to the
Southeast and then to the Southern Plains will move eastward to the East
Coast and stall out overnight Tuesday. By Thursday, the front will move
eastward out over the Western Atlantic, Southeast westward to the Middle
Mississippi Valley. On Tuesday, the boundary will produce showers and
thunderstorms with heavy rain over parts of southeastern New York State,
Delaware, and Pennsylvania. Therefore, the WPC has issued a Slight Risk of
excessive rainfall over parts of the northern Mid-Atlantic through
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, the associated front will create showers and moderate to
severe thunderstorms over parts of New York State, Pennsylvania, Maryland,
Delaware, Virginia, and North Carolina. Therefore, the SPC has issued a
Marginal Risk of severe thunderstorms over parts of the
Northeast/Mid-Atlantic through Wednesday morning. The hazards associated
with these thunderstorms are frequent lightning, severe thunderstorm wind
gusts, hail, and a minimal threat of tornadoes.

On Wednesday, the threat of excessive rainfall decreases slightly over the
Northeast. Ongoing showers and thunderstorms will produce moderate to
heavy rain. Therefore, the WPC has issued a Marginal Risk of excessive
rainfall over parts of the Northeast from Wednesday through Thursday
morning. The associated heavy rain will create localized areas of flash
flooding, affecting areas that experience rapid runoff with heavy rain.

Meanwhile, along the western end of the front mentioned above, over parts
of the Central/Southern Plains, showers and severe thunderstorms will
develop over parts of southern Kansas, Oklahoma, extreme southwestern
Missouri, and northwestern Arkansas. Therefore, the SPC has issued an
Enhanced Risk of severe thunderstorms over parts of the Central/Southern
Plains through Wednesday morning. The hazards associated with these
thunderstorms are frequent lightning, severe thunderstorm wind gusts,
hail, and a few tornadoes. Additionally, there is a threat of two-inch or
greater hail over the area through Wednesday morning.

Moreover, upper-level energy and a nearby front will produce showers and
severe thunderstorms over parts of South Dakota and Nebraska. Therefore,
the SPC has issued a Slight Risk of severe thunderstorms over the
Northern/Central Plains through Wednesday morning. The hazards associated
with these thunderstorms are frequent lightning, severe thunderstorm wind
gusts, hail, and a few tornadoes. Additionally, there is a threat of
two-inch or greater hail over parts of South Dakota and Nebraska through
Wednesday morning.On Wednesday, the threat of severe thunderstorms moves
eastward and decreases slightly over the Lower Mississippi/Tennessee
Valleys. Therefore, the SPC has issued a Slight Risk of severe
thunderstorms over parts of the Lower Mississippi/Tennessee Valleys from
Wednesday into Thursday morning. The hazards associated with these
thunderstorms are frequent lightning, severe thunderstorm wind gusts,
hail, and a few tornadoes.

Further, upper-level energy moves eastward over the Upper Midwest,
producing showers and severe thunderstorms on Wednesday. Therefore, the
SPC has issued a Slight Risk of severe thunderstorms over parts of the
Upper Mississippi Valley from Wednesday into Thursday morning. The hazards
associated with these thunderstorms are frequent lightning, severe
thunderstorm wind gusts, hail, and a few tornadoes.

Meanwhile, upper-level impulses and a developing upper-level trough will
trigger scattered showers and thunderstorms over parts of the Great Basin,
Pacific Northwest, Northern California, and the Northern Rockies on
Tuesday, continuing into Thursday. 

Furthermore, wildfire smoke from Canada will reduce air quality over parts
of the Upper Mississippi Valley and Great Lakes, prompting Air Quality
Warnings over the area. The smoke could reduce the air quality farther
south into the Ohio Valley.

Lastly, an upper-level high over the south-central portion of the country,
along with high temperatures and temperatures not cooling off much
overnight, have contributed to Excessive Heat Warnings and Heat Advisories
over most of Texas, Southwest, southern New Mexico, southeastern Oklahoma,
southern Arkansas, Louisiana, southern Mississippi, southwestern Alabama,
and Florida Panhandle.



Ziegenfelder









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