019
FXUS62 KCHS 132317
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
717 PM EDT Wed Aug 13 2025

.SYNOPSIS...
High pressure will prevail across the region through Friday. A
weak cold front will move through Saturday, followed by high
pressure into the middle of next week.

&&

.NEAR TERM /THROUGH THURSDAY/...
This afternoon, conditions across the forecast area featured
temperatures in the low to mid 90s with dewpoints in the upper
70s to low 80s. Heat index values ranged from 106 to 110 degrees
across the coastal corridor. Heat Advisory remains in effect
until 6 PM.

SPC mesoanalysis this afternoon indicated a corridor of SBCAPE
around 5000 J/kg with MLCAPE around 3500 J/kg. As a slow-moving sea
breeze slides inland, scattered showers and thunderstorms may
develop along and ahead of the sea breeze. Modified soundings
indicates that areas of 1000 J/kg may develop across the region. It
is possible that a thunderstorm or two could develop strong gusty
winds. Later this evening, a strong mid-level vort max is expected
to track north across GA. Forcing associated with this feature may
lead to another round of thunderstorms across SE GA and portions of
inland GA/SC. It is possible that these thunderstorms may result in
localized rainfall amounts in excess of 2 inches across SE GA, a
Flood Advisory or two may be needed late this afternoon and evening.
Convection should generally dissipate after midnight. Low
temperatures are forecast to range from the mid 70s inland to the
upper 70s along the coast.

&&

.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
A broad upper ridge will remain over the southwest Atlantic
through Thursday. Guidance is in good agreement that a potent
shortwave will move through central GA/SC midday Thursday,
potentially being a focus for convection tracking across our
inland zones. Convective indices will favor a few strong to
severe thunderstorms, though if the activity develops earlier in
the day there would be less instability to work with. Heat
indices expected to top out in the 100-105F range on Thursday.

Friday looks a bit hotter though with potentially less
convective coverage due to less forcing. A fairly large swath of
108-112F heat indices across southeast GA and far southern SC
may warrant a Heat Advisory.

A weak cold front may sag into the area on Saturday, bringing
slightly cooler temps to southern SC but with greater shower and
tstm coverage across much of the area. PWATs around 2.3" and a
slow-moving boundary could favor locally heavy rainfall.

&&

.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
High pressure at the surface and aloft will produce typical
summertime weather Saturday night through Tuesday. Temps will be
fairly close to normal with mainly isolated diurnal convection.

&&

.AVIATION /23Z WEDNESDAY THROUGH MONDAY/...
00Z TAFs - Aviation concerns continue to revolve around
thunderstorm coverage, with main area of concern now moving
across southeastern Georgia. Will likely see showers and
thunderstorms continue over the next couple hours across
southeastern Georgia, with additional storms possible more
inland and away from the coast as we head into the overnight
hours. MVFR cigs, in addition to light showers, may push in from
the inland areas towards the coast late tomorrow morning into
the afternoon hours before another round of thunderstorms become
possible mainly across southeastern South Carolina.

Extended Aviation Outlook: Brief flight restrictions will be
possible with afternoon showers/thunderstorms.

&&

.MARINE...
Tonight: The pattern should generally support south winds between 10
to 15 kts. Seas should remain between 2 to 3 ft.

High pressure will maintain sub-advisory conditions over the
waters Thursday through Tuesday. Swells from distant TS Erin
will likely begin impacting the marine zones Monday night.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...None.
SC...None.
MARINE...None.

&&

$$

NEAR TERM...NED
SHORT TERM...JRL
LONG TERM...JRL
AVIATION...APT/JRL
MARINE...JRL/NED