Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
400 AM EDT Wed May 07 2025

Valid 12Z Wed May 07 2025 - 12Z Fri May 09 2025

...Widespread showers and storms to bring scattered to numerous instances
of flash flooding to portions of the central Gulf Coast Wednesday...

...Pesky weather pattern of showers and storms across much of the
Mid-Atlantic and Northeast continues...

...Cooler, well below average temperatures persist across much of the
southern tier of the country as the north-central and western U.S. see
above average temperatures...

The Omega block that has dominated the upper-level pattern across the
CONUS the last few days, anchored by an eastern upper-low over the Ohio
Valley and a second, western upper-low over the Southwest will finally
begin to evolve through mid-week, though general upper troughing over the
East and South will continue to bring unsettled weather. The upper-low
over the Southwest has begun to progress eastward over the southern Plains
and Lower Mississippi Valley. At the surface, a quasi-stationary frontal
boundary reinforced by ongoing convection overnight stretches east to west
just north of the Gulf Coast. Anomalously high Gulf moisture pooling along
the boundary and upper-level support from the approaching low will provide
a focus for yet another complex of storms expected to develop along the
western Gulf Coast and move eastward along the boundary through the
central Gulf Coast. Saturated soils from overnight rainfall and
long-duration, heavy rainfall from the second complex to move through
today will bring the risk of scattered to numerous instances of flash
flooding, with a Moderate Risk of Excessive Rainfall (level 3/4) for
southeastern Louisiana and a broader Slight Risk (level 2/4) along the
central Gulf Coast. Warmer temperatures south of the boundary across
portions of the Texas Gulf Coast/south Texas will lead to enough
instability for some stronger, severe thunderstorms with the Storm
Prediction Center outlining a Slight Risk (level 2/5) of severe weather,
mainly for the threat of large hail. Additional widespread storms are
expected throughout a broad warm sector ahead of a secondary cold front
across the Tennessee/Middle Mississippi Valleys and central Plains, with
some locally heavy rainfall and isolated flash flooding possible. Another
round of storms is expected Thursday from western/southern Texas east
along the Gulf Coast as the boundary remains in place, with locally heavy
rainfall expected and isolated flash flooding possible. A more focused
corridor of storms over saturated soils across Louisiana may lead to a few
more scattered instances of flash flooding, with a Slight Risk of
Excessive Rainfall in place to cover this threat. Similar to Wednesday, a
broad area of showers and storms is also expected further north ahead of
the secondary cold front over much of the Southeast.

Some lingering showers are expected across the interior Northeast today as
the other upper-low that had been anchored over the Ohio Valley finally
shifts eastward as an open wave over the Atlantic. However, upper-level
shortwave energy dropping southward from Canada and an accompanying
surface cold front sweeping southeastward will bring another round of
storms to the Northeast/Mid-Atlantic on Thursday. Increasing moisture
ahead of the boundary and the tendency for storms to move northeastward
parallel to the boundary will bring some locally heavier rainfall totals,
particularly focused across some of the higher terrain of northeastern
Pennsylvania, northwestern New Jersey, and southern New York, where
another Slight Risk of Excessive Rainfall is in effect for scattered
instances of flash flooding. Elsewhere, daily thunderstorm chances are
expected along the Atlantic coast of Florida ahead of the stationary
boundary along the Gulf Coast, with some heavier downpours and isolated
flash flooding possible. Some lingering isolated to scattered showers and
thunderstorms will also continue throughout the Four Corners region as the
Southwest upper-low slowly departs the region. A Pacific system will bring
some light precipitation chances to the Pacific Northwest Wednesday and
then inland through the northern Rockies/High Plains Thursday. 

Cooler, below average temperatures will continue across much of the
southern U.S. from the Southwest through the central/southern Plains and
into the Southeast with the upper-low/broad troughing dominating the
pattern and widespread precipitation chances. Highs will generally range
in the 60s and 70s with some 80s expected through the Deserts and for more
southern locations across Texas and east along the Gulf Coast. Closer to
average temperatures will return to much of the Great Lakes/Ohio Valley
Wednesday as the Upper-low departs the region, with highs into the 70s. A
cold front will bring cooler, below average conditions back to the Great
Lakes Thursday as highs fall into the 50s and 60s. In contrast, well above
average temperatures will continue across the northern Plains/Upper
Midwest with a lingering upper-high over head, with highs in the 70s to
low 80s. Above to well above average conditions will also expand over much
of the West as a ridge builds northward in the wake of the departing
upper-low, with 60s and 70s across the Pacific Northwest and Interior
West. High temperatures into the 90s will come to the central California
Valleys and Desert Southwest by Thursday. Generally average high
temperatures are expected along the East Coast, with 60s and 70s for New
England and 70s into the 80s south through the Mid-Atlantic and into the
Carolinas. 
  

Putnam


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