Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
425 AM EDT Sun Aug 01 2021

Valid 12Z Sun Aug 01 2021 - 12Z Tue Aug 03 2021

...Showers and thunderstorms with locally heavy rainfall across the
central U.S. will gradually reaches the Gulf Coast during the next couple
of days...

...More rounds of monsoonal moisture expected across the interior western
U.S. with flash flooding possible from the Great Basin to the Rockies...

A cool air mass will continue to make steady progress through the central
and eastern portions of the country today to offer relief to the recent
spell of oppressive heat. Showers and thunderstorms will signal the
arrival of the cool air across the central Plains to the Tennessee Valley
today behind a cold front with multiple low pressure waves. Hot and very
humid conditions will persist for one more day today across the Deep South
where Heat Advisories and some Excessive Warnings are currently in effect.
By Monday, more widespread showers and thunderstorms will keep
temperatures at bay through the Deep South as the front edges closer from
the north.

Meanwhile, a reinforcing cold front will spread showers and some
thunderstorms across the lower Great Lakes today and into northern
New England tonight. This system will attempt to merge with a low
pressure wave forecast to develop today across the Carolinas to help
trigger a period of strong to possibly severe thunderstorms near the
Mid-Atlantic coast. A cool and dry air mass across the northern Plains
will be ushered into the central U.S. and the Northeast behind the front
to begin the new work week. Over the Mid-Atlantic region however, the
front is forecast to stall later on Monday which will encourage the rain
to linger and possibly get heavier near the Carolina coasts Monday night
as another low pressure wave is forecast to develop. More showers and
thunderstorms are expected further south into Florida as well as along the
Gulf Coast where the front is forecast to stall.

In the Pacific Northwest, an influx of monsoonal moisture from the south
should help cool down the temperatures today across the interior sections,
breaking the recent spell of excessive heat. Speaking of monsoonal
moisture, there is no shortage of it across the Intermountain West. The
associated rainfall is welcoming to the drought-stricken West but the
downpours associated with some of the thunderstorms are capable of
producing heavy rainfall rates that could trigger areas of flash flooding.
Locations most at risk for flash flooding are where antecedent soil
conditions are overly saturated or near burn scars. The Excessive
Rainfall threat today shifts into Idaho as well as the southern High
Plains where thunderstorm activities are forecast to be best focused.
More rounds of heavy showers and storms are possible up and down the spine
of the Rockies as well near the Southeast U.S. coast on Monday.

Lastly, Air Quality Alerts remain in effect for portions of the interior
Northwest, Arizona, Colorado, the upper Midwest, the Tennessee Valley and
South Carolina due to smoke associated with wildfires over western North
America being transported into these areas.

Kong