Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
327 AM EDT Sat Jul 23 2022

Valid 12Z Sat Jul 23 2022 - 12Z Mon Jul 25 2022

...Hot & sultry temperatures to engulf much of the Central Plains,
Mid-South, and Northeast coast this weekend....

...Severe thunderstorms capable of producing flash flooding to traverse
the Midwest today & across the Great Lakes on Sunday...

...Monsoonal moisture to gradually bring locally heavy rains and isolated
flash flooding across portions of the Southwest into the Southern Rockies
this weekend...

The "Dog Days of Summer" are unquestionably here as a persistent upper
level ridge set up from the Southern Plains to the Southeast keeps a heat
dome firmly entrenched across much of the eastern half of the Lower 48
this weekend. A large concentration of Heat Advisories are in place within
the Nation's Heartland today while Heat Advisories and even a handful of
Excessive Heat Warnings stretch from southern New England to the Lower
Delaware River Valley and northern DelMarVa Peninsula. Some lingering Heat
Advisories and Excessive Heat Warnings are also in place in parts of
southern Utah and northern Arizona. In these locations, heat indices >105
degrees are anticipated with some areas potentially making a run at heat
indices of 110 degrees. In terms of actual high temps, look for daytime
max temps to eclipse the century mark in the Central Plains and record
breaking high temps from the Central Plains to the Northeast today. Sunday
grows even hotter in the Northeast with some locations reaching 100 for
highs, and heat indices as high as 110 degrees. As if the daytime highs
weren't hot enough on Sunday, record warm morning lows will offer little
relief as they struggle to get any lower the mid-upper 70s both Sunday and
Monday from the Middle Mississippi Valley to the Northeast. An approaching
cold front will cool down parts of the Midwest by late Sunday into Monday,
but searing heat will stick around in the Southern Plains and Mid-South
into early next week.

Today, a potent upper trough tracking across the southern Canadian
Prairies will prompt a strong cold front to sweep across the North-Central
U.S., resulting in an organized severe weather threat across the Midwest.
SPC has issued an Enhanced Risk (threat level 3/5) for portions of the
Upper Mississippi Valley and Great Lakes, which does include the Twin
Cities and Milwaukee metro areas. Damaging winds, large hail, and
tornadoes are all possible within severe storms on Saturday. Some of these
storms across the Midwest may also produce areas of flash flooding,
resulting in a Slight Risk (Threat level 2/4) being issued for a similar
area to SPC's Enhanced Risk. By Sunday, the severe threat looks to extend
from the interior Northeast to the Lower Great Lakes where the SPC has an
elongated Slight Risk area in place. By Monday, the cold front tracks into
the Mid-Atlantic and Ohio/Tennessee Valleys, sparking thunderstorms in
these regions the second half of the day. A Slight Risk for Excessive
Rainfall has been issued for portions of the central Appalachians and into
the Tennessee/Ohio Valley this Monday.

In the Southwest, monsoon showers and thunderstorms will develop each day
with heavy downpours potentially leading to areas of flash flooding. A
stronger push of tropical moisture arrives this weekend, prompting the
issuance of a Slight Risk (threat level 2/4) of Excessive Rainfall in
southeast Arizona both Saturday and Sunday, while a Slight Risk was also
issued for parts of the Colorado Rockies for Sunday. Areas most at risk
for flash flooding are near burn scars, within slot canyons, and atop
soils that have received anomalously heavy rainfall in recent weeks.


Mullinax


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