749
FXUS01 KWBC 200757
PMDSPD

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

Valid 12Z Wed Aug 20 2025 - 12Z Fri Aug 22 2025

...The expanding circulation of Hurricane Erin is expected to
bring tropical storm conditions to the Outer Banks late Wednesday
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. and the Southwest Wednesday-Thursday, and
across the Upper Midwest Thursday...

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

Hurricane Erin, currently northeast of the Bahamas this morning,
is forecast to track north and then northeastward off the East
Coast over the next few days. While the center of the storm will
remain well offshore, the expanding circulation and outer bands of
the storm are expected to bring some impacts to portions of the
East Coast, especially along the North Carolina Outer Banks.
Tropical Storm Warnings are in effect beginning late Wednesday for
the threat of tropical storm force wind gusts, heavy rain/isolated
flash flooding, and a life-threatening storm surge of 2-4 feet.
Large waves could lead to significant beach erosion and overwash,
leaving some roads impassible. Tropical storm conditions are also
possible further north into coastal Virginia where a Tropical
Storm Watch is in effect. A surge of 1-3 feet is expected more
broadly along the coastal Carolinas northward through coastal
Virginia. 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.

Widely scattered thunderstorms are expected over 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
Wednesday, storms 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, clustering storms will lead
to some locally heavy downpours, with isolated flash flooding
possible. Enhanced moisture flowing into southern New England due
to Hurricane Erin could lead to some potentially more significant
rainfall. 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. To the West, Monsoonal moisture and
diurnal instability will help to trigger isolated to scattered
thunderstorms over portions of the Southwest 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 systems passes
through the region. More isolated storms across the northern High
Plains Wednesday will become more numerous as the system moves
into the Upper Midwest Thursday, with some heavy rain and isolated
flash flooding possible.

Dangerous heat is expected to intensify and expand in coverage
over the Southwest the next couple of days and last 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. Heat-advisories remain in effect across portions of the
northern High Plains as highs climb into the 90s to low 100s
Wednesday. A cold front will bring cooler, more seasonable highs
in the 80s Thursday as the focus for hotter temperatures shifts
into portions of the central Plains.  While the coverage of
extreme heat has begun to reduce across the south-central U.S.,
another day of very hot and muggy conditions is still expected
from the ArkLaTex vicinity east into the Lower Mississippi Valley,
with heat indices into the 105-110 degree range, locally into the
110s along portions of the Lower Mississippi Valley. 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.

Putnam


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