Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
301 PM EDT Fri May 09 2025

Valid 00Z Sat May 10 2025 - 00Z Mon May 12 2025

...Soaking rainfall across the Northeast will persist in parts of New
England on Saturday...

...Excessive Rainfall and severe weather to be the focus for the weekend
forecast throughout the Southeast...

...Record warmth expected in parts of the West & Northern Plains today and
into the weekend...

A pair of slow moving storm systems are responsible for prolonged periods
of heavy rain and thunderstorms in the Southeast and the Northeast.
Starting in the Northeast, an area of low pressure will continue to carry
a plume of rich moisture aloft into the region as it tracks through the
Gulf of Maine on Saturday. The heaviest rainfall will be found from the
Catskills on east across much of New England. The Northeast will gradually
dry out throughout the day Saturday with Downeast Maine seeing the last
bands of showers finally depart by the evening. The latest forecast calls
for an additional 1-2 inches of rainfall across much of New England with
localized totals over 2 inches possible through Saturday. With much of the
region sporting saturated and sensitive soils, it is possible for
instances localized flash flooding and minor to isolated moderate river
flooding through Saturday. WPC has issued a pair of Marginal Risks both
tonight and Saturday (threat level 1/4) to highlight the flash flooding
potential that will most likely be confined to poor drainage areas and
urbanized communities.

Farther south, another dawdling storm system is set to produce rounds of
heavy rain and thunderstorms this evening and into the weekend. This storm
system will direct copious amounts of Gulf moisture northward while a
stationary front also acts as a trigger for thunderstorms each day.
Through tonight, WPC has an expansive Marginal Risk for Excessive Rainfall
that stretches from the Lower Mississippi River Valley to as far east as
the Southeast coast. In addition to the Excessive Rainfall potential, the
Storm Prediction Center (SPC) issued a pair of Slight Risks (threat level
2/5) along Florida's Space Coast and in the North Carolina Outer Banks.
SPC's Marginal Risks encompasses much of the same areas of the Southeast
as WPC's Marginal Risk with severe storms capable of producing damaging
winds, large hail, and tornadoes. By Saturday, the upper low responsible
for the onslaught of heavy rain meanders eastward slightly as the
associated surface low lifts northward, placing Alabama, the Florida
Panhandle, and much of southern Georgia in the best position to receive
the heaviest rainfall. Through Sunday, the rainfall forecast calls for as
much as 2-5 inches of rain for much of the Southeast with the Florida
Panhandle and southeast Georgia having the best chances for witnessing the
heaviest amounts. Flash flooding, as well as some cases of river and small
stream flooding, are expected through Sunday and into early next week.
Please visit WPC's Medium Range discussion for more details on the
forecast for Monday onward.

The weather pattern across the Lower 48 is making for dramatic temperature
anomalies that will persist through the next few days. With the pair of
storm systems causing widespread cloud cover for much of the coastal areas
and their associated cold fronts directing cooler temps into the southern
and eastern U.S., temperatures will be below normal from the Rio Grande
Valley of western Texas all the way to the East Coast. Temperature
anomalies will largely be 5-10 degrees below normal with some parts of the
Northeast seeing departures as cool as 15 degrees below normal in some
cases. Early morning frost is possible on Saturday from the upper Ohio
Valley to the central Appalachians. Meanwhile, a large upper level ridge
will park itself over the western and northern U.S. that will foster very
warm temperatures for early-to-mid May, making for a quite summer-like
Mother's Day Weekend. Some record warmth is possible on Saturday extending
from Southern California to the northern High Plains. Some parts of
Southern California may see high temperatures reach triple digits, while
morning lows may also challenge record warm levels for this time of year.
Temperature anomalies throughout the West are likely to range between
15-25 degrees above normal and will potentially approach 30 degrees above
normal in the Northern Plains by Sunday. NWS's HeatRisk does depict
Moderate to scattered instances of Major heat potential in the Southeast
on Saturday, with Moderate heat impacts showing up in the Northern Plains.
Please visit www.wpc.ncep.noaa.gov/heatrisk/ for more information on the
NWS HeatRisk products.
  
Snell/Mullinax


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