Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
257 PM EDT Wed Jul 24 2024
Valid 00Z Thu Jul 25 2024 - 00Z Sat Jul 27 2024
...Major to locally extreme Heat Risk will expand across the northern High
Plains as heat gradually becomes less intense over the Central Valley of
California and the Great Basin...
...Scattered showers and thunderstorms will extend across the southern
tier states to the East Coast with Excessive Rainfall probable along the
Texas coast through Thursday...
...Scattered to Severe Thunderstorms possible across portions of the
Northern Appalachians/interior Northeast tonight...
...Monsoonal thunderstorms continue across the Great Basin and into the
Four Corners region with threats of localized flash flooding while fire
weather danger emerges over the interior Northwest...
A slow-to-evolve summertime weather pattern will continue across much of
the U.S. mainland while a more progressive Pacific cold front sweeps
across the northwestern part of the country through the next couple of
days. Under this weather pattern, unsettled weather and relatively cool
temperatures for July will continue across the eastern half of the country
as the ongoing heat wave over the western U.S. gradually becomes less
intense with the arrival of the Pacific cold front. The stronger forcing
associated with this front will push the heat dome east of the Great
Basin, resulting in the expansion of major to locally extreme Heat Risk
across the northern High Plains over the next couple of days. High
temperatures are forecast to reach well up into the 100s to near 110 at
the hottest location over the northern High Plains through Thursday with
little to no rainfall expected. Meanwhile, the heat will gradually become
less intense over the Central Valley of California and the Great Basin
with time. Please continue to practice heat safety as the heat spreads
into the northern High Plains.
By Thursday night into Friday morning, the cold front will make its way
through the northern Rockies into the High Plains with cooler air arriving
but with very little moisture to work with. Meanwhile, lightning
associated with dry thunderstorms triggered by the passage of the cold
front will result in critical fire danger over the interior northwestern
U.S. In addition, monsoonal thunderstorms will continue across the Great
Basin/southern Sierra Nevada tonight and become more numerous over the
Four Corners region Thursday into Friday with the threat of localized
flash flooding over the next couple of days.
In contrast to the heat in the West, cooler than normal temperatures will
prevail across the mid-section of the country to portions of the eastern
U.S. where a stalled front will keep plenty of clouds along with scattered
thunderstorms. Some scattered thunderstorms this afternoon may develop
into severe storms by this evening across portions of northwestern
Pennsylvania into central to eastern upstate New York. Thunderstorms are
not expected to be severe, but they could result in localized flooding
issues from time to time across the southern tier states as well as up and
down the East Coast. There's a persistent Slight Risk of Excessive
Rainfall in effect over portions of the Carolinas through Friday where
storms are expected to continue reoccurring.
A coastal front interacting with a broad upper-level southwesterly flow
could set off heavy rain and thunderstorms near the Texas coast into
southwestern Louisiana where flash flooding is probable. A Moderate Risk
of Excessive Rainfall leading to Flash Flooding is in effect from Texas'
eastern Gulf Coast into Louisiana's western coast tonight and then
expanding in coverage into Texas' central Gulf Coast on Thursday.
Elsewhere, some scattered thunderstorm activity is possible across
portions of northern Maine late Thursday afternoon.
Kebede/Kong
Graphics available at
https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php