Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
411 PM EDT Fri Jul 14 2023

Valid 00Z Sat Jul 15 2023 - 00Z Mon Jul 17 2023

...There is a Moderate Risk of excessive rainfall over parts of New
England on Friday and again on Sunday...

...There is an Enhanced Risk of severe thunderstorms over parts of the
Central Plains on Friday...

...Excessive Heat Warnings and Advisories from California/Great Basin to
the Central/Southern Plains, Central Gulf Coast...

...Air Quality alerts over parts of the Upper Midwest and Ohio Valley...

A weakening front near the East Coast will slowly dissipate by Saturday.
The boundary will create showers and thunderstorms with heavy. Therefore,
the WPC has issued a Moderate Risk of excessive rainfall over parts of New
England through Saturday morning. The associated heavy rain will create
numerous areas of flash flooding. Furthermore, many streams may flood,
potentially affecting larger rivers. The showers and thunderstorms will
continue through Saturday afternoon near the East Coast.

Moreover, a wave of low pressure and associated fronts will produce
showers and severe thunderstorms over parts of Kansas, far western
Missouri, Northern Oklahoma, and southern Nebraska. Therefore, the SPC has
issued an Enhanced Risk of severe thunderstorms over parts of the
Central/Southern Plains through Saturday morning. The hazards associated
with these thunderstorms are frequent lightning, severe thunderstorm wind
gusts, hail, and a few tornadoes. In addition, there is an increased risk
of severe thunderstorm wind gusts of 65 knots over eastern Kansas.

Further, another front will move eastward from the Central Plains to the
East Coast on Saturday. The boundary will produce showers and
thunderstorms with heavy rain over parts of the Northeast, Central
Appalachians, Mid-Atlantic, and the Southern High Plains. Therefore, the
WPC has issued a Slight Risk of excessive rainfall with these
thunderstorms over three areas, the Northeast, Central Appalachians, and
Southern High Plains, from Saturday into Sunday morning. The associated
heavy rain will create mainly localized areas of flash flooding, with
urban areas, roads, and small streams the most vulnerable.

On Sunday, the threat of excessive rainfall increases over parts of the
Northeast as showers and thunderstorms create heavy rain. Therefore, the
WPC has issued a Moderate Risk of excessive rainfall over parts of New
England on Sunday. The associated heavy rain will create numerous areas of
flash flooding. Furthermore, many streams may flood, potentially affecting
larger rivers.

In contrast, the threat of severe thunderstorms decreases slightly. As the
front over the Plains moves eastward into the Ohio Valley/Lower Great
Lakes, the system will produce showers and moderate to severe
thunderstorms over the Ohio Valley, Central/Southern Appalachians,
Tennessee Valley, and Mid-Atlantic. Therefore, the SPC has issued a
Marginal Risk of severe thunderstorms over parts of the Ohio Valley,
Central/Southern Appalachians, Tennessee Valley, and Mid-Atlantic from
Saturday into Sunday morning. The hazards associated with these
thunderstorms are frequent lightning, severe thunderstorm wind gusts, and
a threat of tornadoes and hail.

The threat of severe thunderstorms remains the same over the Northeast on
Sunday. Therefore, on Sunday, the SPC has issued a Marginal Risk of severe
thunderstorms over parts of the Northeast northern Mid-Atlantic. The
hazards associated with these thunderstorms are frequent lightning, severe
thunderstorm wind gusts, and a threat of tornadoes and hail.

Meanwhile, upper-level high develops over  California/Great Basin eastward
to Texas and Louisiana, bringing with the high, hot high temperatures and
temperatures not cooling off much overnight, which have contributed to
Excessive Heat Warnings and Heat Advisories over California, Nevada,
Arizona, southern New Mexico, eastern Oklahoma, most of Texas, Arkansas,
Louisiana, Mississippi, and Alabama. In addition, the ridge will bring an
extremely dangerous heat wave over the Southwest into the weekend and
likely peak in intensity on Sunday for much of the region. Dangerous heat
may continue into next week for parts of the region. All-time heat records
could be approached or reached at some locations in the Southwest. The
records heat would be most likely on Sunday, particularly in the San
Joaquin Valley, Mojave Desert, and Great Basin regions. Phoenix is also
likely to register its hottest week on record by 7-day average
temperature. Take the heat seriously and avoid time outdoors. Temperatures
will reach levels that would pose a health risk, and be potentially
deadly, to anyone without effective cooling and/or adequate hydration.
Heat is the leading weather-related killer in the U.S.

Lastly, wildfire smoke from Western Canada will reduce air quality over
parts of the Upper Mississippi Valley, Great Lakes, and Western Ohio
Valley, prompting Air Quality Warnings over the area. 


Ziegenfelder


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