251
FXUS62 KCHS 151047
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
647 AM EDT Tue Sep 15 2026

.WHAT HAS CHANGED...
All Key Messages and sections were updated.

&&

.KEY MESSAGES...
- 1) Minor coastal flooding is possible with the midday high
  tide along Charleston and coastal Colleton Counties.

- 2) There is a High risk of rip currents for the GA beaches
  through Wednesday.

- 3) Not as hot today through Thursday, followed by above
  normal temperatures Friday into the weekend. Increasing rain
  chances this weekend.

&&

.DISCUSSION...
KEY MESSAGE 1: Minor coastal flooding is possible with the midday
high tide along Charleston and coastal Colleton Counties.

Northeast winds will strengthen this morning, becoming strong and
gusty. These winds will cause tidal departures to increase.
The Charleston Harbor astronomical tide will be 5.98 ft MLLW at
11:46 AM. The tidal departure would need to be just over 1 ft for
the minor coastal flooding threshold of 7 ft MLLW to be reached.
Guidance indicates this could briefly be achieved, so a Coastal
Flood Advisory may be needed. No coastal flooding is expected
further south along the far southern South Carolina and Georgia
coasts.

KEY MESSAGE 2: There is a High risk of rip currents for the GA
beaches through Wednesday.

Northeast winds will strengthen this morning, becoming strong and
gusty this afternoon, and persisting through Wednesday. This will
lead to an elevated east northeast swell along our coast this
afternoon through Wednesday. The strongest winds and highest seas
should be along our GA coast. This is where there is a High risk of
rip currents through Wednesday. Along our SC coast, there is a
Moderate risk of rip currents through Wednesday. Winds and seas
should trend lower on Thursday, reducing the risk of rip currents
along our coast.

KEY MESSAGE 3: Not as hot today through Thursday, followed by
above normal temperatures Friday into the weekend. Increasing
rain chances this weekend.

Satellite and KCLX shows the backdoor or wedge front pushing south
across the forecast area this morning. In the wake of the front,
northeast winds will increase to 10 to 15 mph with gusts into the
20s. Northeast winds should bring cooler llvl thicknesses across the
forecast area, building a late-summer CAD. Temperatures will peak
several degrees lower than yesterday, ranging from the mid to upper
80s along the coast to the low 90s inland. During the afternoon,
scattered showers and thunderstorms are forecast to develop along
the front, generally tracking across SE GA and adjacent waters.

Wednesday and Thursday, wedged high pressure will remain across the
region, maintaining a nose of drier air with cooler llvl
thicknesses. High temperatures are forecast to range around normal,
generally in the mid to upper 80s. Stable conditions across the CWA
should yield dry conditions both days.

Nearly a 600dm ridge will remain centered around southern
Appalachians today through Wed, then sliding west on Thursday. Other
than scattered showers and thunderstorms this afternoon, dry weather
is expected through the rest of the work week. On Friday, GFS
and ECMWF indicate a closed H5 low tracking west across FL over
the Gulf. The closed low will pass over the Mississippi Delta by
Sunday afternoon. Circulation around the low will increase
moisture across the Southeast U.S. this weekend. Warm and moist
conditions should favor scattered to numerous thunderstorms,
especially along the sea breeze, this weekend.

&&

.AVIATION /09Z TUESDAY THROUGH SATURDAY/...
Prior to the 12Z TAFs, IR satellite and KCLX indicated that the
backdoor or wedge front was advancing south across the Savannah
River. Wedged high pressure will increase across the terminals
today. Once mixing begins this morning, east-northeast winds
should develop gusts between 20-25 kts. Gusty east-northest
winds will likely continue through the rest of the daylight
hours. Gusts should end this evening.

At KSAV, the backdoor front should reach the terminal just after
the onset of the 12Z TAFs, turning winds from the northeast. By
14Z, gusts between 20-25 kts should develop across the terminal
and will remain until this evening. Latest HREF indicates
scattered showers and thunderstorms may track across KSAV
between 16-20Z, highlighted with a PROB30.

Extended Aviation Outlook: Prevailing VFR conditions with the chance
of breezy northeasterly winds (gusts up to 20 kts possible) on
Wednesday and Thursday afternoons. Otherwise, it will be fairly dry
until Friday when rain chances increase again.

&&

.MARINE...
Today through Thursday evening: A backdoor cold front will push
across the marine zones this morning. In the wake of the front,
winds across the nearshore and outer waters will turn from the east-
northeast and strengthen into the 20s, with gusts in the upper 20s
to near 30 kts. Small Craft Advisories have been issued for the
nearshore SC/GA waters along with the outer GA waters. Across the
Charleston Harbor, gusts should settle into the low 20 kts,
remaining just below Small Craft Advisory criteria. Cold air damming
pattern should linger through Thursday, supporting gusty winds.
Wave heights will build through today, peaking tonight between
5 to 7 ft. Six foot seas may linger over portions of the waters
through Thursday. Small Craft Conditions should end Thursday
evening.

More favorable marine conditions are expected on Friday into
Saturday as winds settle to around 10 kt and seas lower to 2 to 3 ft
on Saturday. Mariners should continue to monitor the latest forecast
before heading offshore.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...High Risk for Rip Currents through this evening for GAZ217-219-239-
     241.
SC...None.
MARINE...Small Craft Advisory until 8 PM EDT Thursday for AMZ360.
     Small Craft Advisory until 10 PM EDT Thursday for AMZ362.
     Small Craft Advisory from 11 AM this morning to 1 AM EDT
     Friday for AMZ364-384.

&&

$$