711
FXUS01 KWBC 202019
PMDSPD

Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
400 PM EDT Wed Aug 20 2025

Valid 00Z Thu Aug 21 2025 - 00Z Sat Aug 23 2025

...The expansive circulation of Hurricane Erin is expected to
bring tropical storm conditions for the eastern shores of North
Carolina and Virginia tonight to Thursday...

...Life-threatening surf and rip currents will be churning up and
down the East Coast through the next couple of days...

...Scattered thunderstorms will bring locally heavy rain and an
isolated flash flood threat to portions of the eastern to
south-central U.S., the Southwest tonight into Thursday, and
across the Upper Midwest late Thursday...

...Dangerous heat wave begins to build over the Southwest late
this week...

Hurricane Erin, with its continually expanding circulation, is
poised to regain major hurricane intensity as it tracks northward
off the coast of the Southeast U.S. this Wednesday afternoon.  The
eye of Erin is forecast to make its closest approach to the Outer
Banks of North Carolina Thursday morning.  While the core of Erin
will likely remain offshore, the expansive circulation of the
hurricane is forecast to bring tropical-storm-force winds with
some squally heavy showers from the outer rainbands of the storm
for the eastern shores of North Carolina and Virginia where
Tropical Storm Warnings are in effect.  In addition, a
life-threatening storm surge of 2-4 feet is forecast from Cape
Lookout to Duck, North Carolina, while 1-3 feet of storm surge is
expected more broadly northward through coastal Virginia.  Large
waves could lead to significant beach erosion and overwash,
leaving some roads impassible.  Interests further north along the
Mid-Atlantic and southern New England coasts should monitor the
progress of Erin as strong winds are possible Thursday and Friday.
 Life-threatening surf and rip currents are also expected to
continue along the East Coast through the next couple of days.
Beachgoers should follow advice from lifeguards, local
authorities, and beach warnings flags, and if in doubt do not go
out.  By Friday, drier and cooler air will be ushered into the
East Coast behind the rapidly-departing hurricane.

Widely scattered thunderstorms are expected for much of the
eastern to south-central U.S. over the next couple of days as a
cold front slowly sags southward through the region.  For this
evening, lines of thunderstorms are forecast from southern New
England southwest through the Mid-Atlantic, Appalachians,
Tennessee/Lower Mississippi Valleys, and into the southern Plains.
 Plentiful moisture and the expected slow-moving, linear
organization of storms will lead to some locally heavy downpours,
with isolated flash flooding possible.  Atlantic moisture
interacting with a coastal front on the outer circulation of Erin
could lead to a period of moderate rainfall for southern New
England through this evening/tonight.  Storm chances will slide
further south on Thursday from the central/southern Appalachians
southwest along the Gulf Coast and into eastern/southern Texas,
with isolated instances of flash flooding remaining possible.  By
later in the afternoon on Friday, scattered thunderstorms are
expected to develop closer toward the Gulf Coast across the Deep
South as the slow-moving front dips farther south.

In the West, monsoonal moisture and diurnal instability will help
to trigger isolated to scattered thunderstorms over portions of
the Southwest through the next couple of days.  Brief but heavy
downpours could lead to some isolated flash flooding, especially
for more sensitive areas including steep terrain, burn scars, and
in urban areas.  Another area of storms is expected across the
north-central U.S. as a frontal system passes through the region.
More isolated storms across the northern High Plains through
tonight will become stronger and more numerous as the system moves
across the northern Plains toward the Upper Midwest on Thursday
when some heavy rain and isolated flash flooding will be possible.

Dangerous heat is expected to intensify and expand in coverage
over the Southwest the next couple of days and into into the
weekend under the influence of a strong upper-level high.
Widespread heat-related warnings and advisories are in effect
across much of southern California as highs climb into the 90s and
100s, and across the Desert Southwest as highs climb into the
110s.  This dangerous level of heat will pose a threat to anyone
without effective cooling and adequate hydration.  Highs into the
90s more broadly across the region will still pose a threat to
anyone more sensitive to heat or engaging in strenuous outdoor
activities.  Temperatures are also expected to begin warming
across the Pacific Northwest after a cooler than average start to
the week.  A cold front will bring cooler, more seasonable highs
in the 80s for the northern High Plains on Thursday as the focus
for hotter temperatures shifts into portions of the central
Plains.  Elsewhere, locally very hot and muggy conditions are also
expected in South Florida, with heat indices into the 100s
prompting Heat Advisories here as well.  High temperatures will
remain well below average across much of the Northeast as the area
remains north of a frontal boundary, with highs mainly in the 60s
and 70s. Highs will generally be seasonable from the Southeast to
the Southern Plains, with highs in the 90s, and across the
Midwest, with 80s further south and 70s further north. Elevated
fire danger is forecast to emerge across the Great Basin and
northern Rockies behind a cold front.

Kong/Putnam


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