Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
340 PM EDT Sun Jul 02 2023

Valid 00Z Mon Jul 03 2023 - 00Z Wed Jul 05 2023

...Heavy rain with the risk of localized flash flooding and severe weather
stretches from the Northeast to the Ohio/Tennessee Valley through
tonight...

...Heat wave relaxes across the South but conditions will remain
excessively hot over much of the West Coast and Desert Southwest...

...Much above normal temperatures for portions of the northern Plains and
upper Midwest ahead of rain/storm chances Monday into Independence Day...

A slow moving storm system stretching from the Ohio Valley to the
Northeast is expected to exit the region over the next few days, but will
continue to spread scattered showers and thunderstorms throughout the
region. Areas of locally heavy rain are possible within the broad
shower/storm activity impacting the eastern third of the Nation, with
greater chances for flash flooding closer to a stationary boundary
extending from the Lower Great Lakes to southern New England. Here, a
Slight Risk (level 2/4) of Excessive Rainfall is in effect through Monday
morning due to the threat of scattered flooding. Just to the south within
a warmer and more unstable airmass, thunderstorms may turn severe across
parts of the Tennessee Valley and Mid-Atlantic. Damaging winds and
isolated tornadoes are most likely across Kentucky through early evening,
with a isolated damaging wind and large hail threat extending towards the
Mid-Atlantic and Tennessee Valley. By Monday, much of the upper level
forcing is expected to weaken as the associated upper trough gets strung
out across the Northeast. Still, scattered showers and thunderstorms may
produce additional isolated flash flooding concerns across the Northeast
and Mid-Atlantic. A few thunderstorms may turn severe across the
Mid-Atlantic. The lingering frontal boundary along the East Coast will
lead to isolated thunderstorm chances into July 4th as well.

The relaxing heat wave will keep oppressive heat indices throughout the
Southeast and immediate Gulf Coast on Monday before confining southward
even more on Independence Day. Heat indices could approach 105-110 degrees
with high temperatures into the mid-90s, which can be dangerous if
spending an extended amount of time outdoors. Additionally, heat will be
the main story throughout the Desert Southwest and West Coast Monday and
Tuesday. Highs well into the triple digits are forecast throughout the
Central Valley region of California and Desert Southwest. A few daily high
temperature records could be challenged on Monday, before the
record-breaking heat potential shifts up the West Coast into northern
California and western Oregon. Here, highs are forecast to reach into the
90s and low 100s on Tuesday.

Elsewhere, thunderstorm chances remain across the central and southern
High Plains today, with potential for localized heavy rain and damaging
wind gusts. By Monday, a potent cold front entering the northern Plains
will spark another area of scattered thunderstorms and extend from
south-central Montana to the Upper Midwest. Temperatures ahead of this
front will be very warm, with into the mid-90s across parts of Minnesota
and South Dakota. However, much cooler temperatures will filter in behind
this front over the Northern Rockies and northern High Plains, with highs
as much as 20 to 30 degrees below average on Tuesday.

For Independence Day itself, the greatest storm chances are forecast along
two frontal boundaries draped across the country. Scattered showers and
potentially strong storms are expected to extend from the central High
Plains to the Upper Midwest, as highlighted by a Slight Risk (level 2/5)
for severe weather by the Storm Prediction Center. Otherwise, shower
chances are expected to linger over the Northeast while slow moving storms
develop near a weakening stationary boundary extending from the southern
Mid-Atlantic to the Tennessee Valley.

Snell


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