947
FZUS52 KCHS 180939
CWFCHS

Coastal Waters Forecast
National Weather Service Charleston SC
539 AM EDT Tue Aug 18 2026

South Santee River SC to Altamaha Sound GA out 60 NM, including
Charleston Harbor and Grays Reef National Marine Sanctuary

AMZ300-182300-
539 AM EDT Tue Aug 18 2026

.Synopsis for the coastal waters of south coastal South Carolina
and north coastal Georgia...
The combination of high pressure over the northern Gulf and
surface troughing over the Southeast U.S. will yield a typical
summertime wind pattern over our coastal waters this week, along
with generally low seas.

$$

AMZ340-182300-
Charleston Harbor-
539 AM EDT Tue Aug 18 2026

.TODAY...W winds 5 to 10 kt, becoming SW late. A slight chance of
showers and tstms late.
.TONIGHT...SW winds 5 to 10 kt. A slight chance of showers and
tstms in the evening.
.WED...NW winds 5 kt, becoming SE in the afternoon.
.WED NIGHT...S winds 5 to 10 kt.
.THU...S winds 5 to 10 kt.
.THU NIGHT...S winds 5 to 10 kt.
.FRI...SW winds 10 to 15 kt.
.FRI NIGHT...SW winds 10 to 15 kt. A chance of showers and tstms.
.SAT...SW winds 10 to 15 kt. A chance of showers and tstms.
.SAT NIGHT...SW winds 5 to 10 kt. A chance of showers and tstms.

Winds and waves higher in and near tstms.

Unless otherwise noted, waves 1 foot or less.

Charleston Harbor water temperature 87 degrees.

$$

AMZ360-182300-
Coastal waters from South Santee River to Edisto Beach SC out
20 NM-
539 AM EDT Tue Aug 18 2026

.TODAY...W winds 10 to 15 kt, becoming SW late. Seas 2 to 3 ft.
Wave Detail: SW 3 ft at 5 seconds and SE 2 ft at 8 seconds.
.TONIGHT...SW winds 10 to 15 kt with gusts to 20 kt, becoming W
5 to 10 kt after midnight. Seas 3 ft. Wave Detail: SW 3 ft at
5 seconds and SE 2 ft at 10 seconds.
.WED...NW winds 5 to 10 kt, becoming SE in the afternoon. Seas
2 to 3 ft. Wave Detail: SW 2 ft at 5 seconds and SE 2 ft at
10 seconds.
.WED NIGHT...S winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: S
2 ft at 5 seconds and SE 2 ft at 9 seconds.
.THU...S winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: S 2 ft at
5 seconds and SE 2 ft at 9 seconds.
.THU NIGHT...S winds 10 to 15 kt. Seas 2 to 3 ft. Wave Detail: S
2 ft at 5 seconds and SE 2 ft at 8 seconds.
.FRI...SW winds 10 to 15 kt. Seas 2 to 3 ft.
.FRI NIGHT...SW winds 10 to 15 kt. Seas 3 ft. A chance of showers
and tstms.
.SAT...SW winds 10 to 15 kt. Seas 2 to 3 ft. A chance of showers
and tstms.
.SAT NIGHT...SW winds 10 to 15 kt. Seas 3 ft. A chance of showers
and tstms.

Winds and seas higher in and near tstms.

$$

AMZ362-182300-
Coastal waters from Edisto Beach SC to Savannah GA out 20 NM-
539 AM EDT Tue Aug 18 2026

.TODAY...W winds 10 to 15 kt with gusts to 20 kt, becoming SW
5 to 10 kt early this afternoon, then increasing to 10 to 15 kt
late. Seas 2 to 3 ft. Wave Detail: SW 2 ft at 4 seconds and SE
2 ft at 8 seconds.
.TONIGHT...SW winds 10 to 15 kt with gusts to 20 kt, becoming W
after midnight. Seas 2 to 3 ft. Wave Detail: SW 2 ft at 4 seconds
and SE 2 ft at 9 seconds.
.WED...W winds 5 to 10 kt, becoming SW in the afternoon. Seas
2 to 3 ft. Wave Detail: SW 2 ft at 4 seconds and SE 2 ft at
10 seconds.
.WED NIGHT...S winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: S
2 ft at 4 seconds and SE 2 ft at 9 seconds.
.THU...S winds 5 to 10 kt. Seas 2 ft. Wave Detail: S 2 ft at
5 seconds and SE 2 ft at 9 seconds.
.THU NIGHT...S winds 10 to 15 kt. Seas 2 to 3 ft. Wave Detail: S
2 ft at 4 seconds and SE 2 ft at 8 seconds.
.FRI...S winds 10 to 15 kt. Seas 2 to 3 ft.
.FRI NIGHT...SW winds 10 to 15 kt. Seas 2 to 3 ft. A chance of
showers and tstms.
.SAT...SW winds 10 to 15 kt. Seas 2 to 3 ft. A chance of showers
and tstms.
.SAT NIGHT...SW winds 10 to 15 kt. Seas 2 to 3 ft. A chance of
showers and tstms.

Winds and seas higher in and near tstms.

$$

AMZ364-182300-
Coastal waters from Savannah GA to Altamaha Sound GA out 20 nm,
including Grays Reef National Marine Sanctuary-
539 AM EDT Tue Aug 18 2026

.TODAY...W winds 10 to 15 kt, becoming SW 5 to 10 kt this
afternoon. Seas 2 to 3 ft. Wave Detail: SW 2 ft at 4 seconds and
SE 2 ft at 8 seconds.
.TONIGHT...SW winds 10 to 15 kt, becoming W after midnight. Seas
2 to 3 ft. Wave Detail: S 2 ft at 4 seconds and SE 2 ft at
9 seconds. A slight chance of showers and tstms in the evening.
.WED...W winds 5 to 10 kt, becoming S in the afternoon. Seas 2 to
3 ft. Wave Detail: SW 2 ft at 4 seconds and SE 2 ft at
10 seconds.
.WED NIGHT...SW winds 5 to 10 kt. Seas 2 ft. Wave Detail: S 2 ft
at 4 seconds and SE 2 ft at 9 seconds.
.THU...SW winds 5 to 10 kt, becoming S 10 to 15 kt in the
afternoon. Seas 2 ft. Wave Detail: S 2 ft at 4 seconds and SE
2 ft at 9 seconds.
.THU NIGHT...S winds 10 to 15 kt. Seas 2 to 3 ft. Wave Detail: S
2 ft at 4 seconds and SE 1 foot at 8 seconds.
.FRI...S winds 10 to 15 kt. Seas 2 to 3 ft. A slight chance of
showers and tstms.
.FRI NIGHT...SW winds 10 to 15 kt. Seas 2 to 3 ft. A chance of
showers and tstms.
.SAT...SW winds 10 to 15 kt. Seas 2 ft. A chance of showers and
tstms.
.SAT NIGHT...SW winds 10 to 15 kt. Seas 2 to 3 ft. A chance of
showers and tstms.

Winds and seas higher in and near tstms.

$$

AMZ380-182300-
Waters from South Santee River SC to Edisto Beach SC extending
from 20 to 60 NM-
539 AM EDT Tue Aug 18 2026

.TODAY...W winds 10 to 15 kt. Seas 3 to 4 ft. Wave Detail: SW
3 ft at 5 seconds and SE 2 ft at 9 seconds.
.TONIGHT...SW winds 10 to 15 kt, becoming W 5 to 10 kt after
midnight. Seas 3 to 4 ft. Wave Detail: SW 3 ft at 5 seconds and
SE 2 ft at 10 seconds.
.WED...W winds 5 to 10 kt, becoming S in the afternoon. Seas
3 ft. Wave Detail: SW 2 ft at 5 seconds and SE 2 ft at
10 seconds.
.WED NIGHT...S winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: SW
2 ft at 5 seconds and SE 2 ft at 9 seconds.
.THU...S winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: SW 2 ft
at 4 seconds and SE 2 ft at 8 seconds.
.THU NIGHT...S winds 10 to 15 kt. Seas 2 to 3 ft. Wave Detail: S
2 ft at 4 seconds and SE 2 ft at 8 seconds.
.FRI...SW winds 10 to 15 kt. Seas 3 ft.
.FRI NIGHT...SW winds 10 to 15 kt. Seas 3 ft. A chance of showers
and tstms.
.SAT...SW winds 10 to 15 kt. Seas 3 ft. A chance of showers and
tstms.
.SAT NIGHT...SW winds 15 kt. Seas 3 to 4 ft. Showers likely with
a chance of tstms.

Winds and seas higher in and near tstms.

$$

AMZ382-182300-
Waters from Edisto Beach SC to Savannah GA extending from 20 to
60 NM-
539 AM EDT Tue Aug 18 2026

.TODAY...W winds 10 to 15 kt with gusts to 20 kt, becoming SW
late. Seas 3 to 4 ft. Wave Detail: SW 3 ft at 5 seconds and SE
2 ft at 8 seconds.
.TONIGHT...SW winds 10 to 15 kt. Seas 3 to 4 ft. Wave Detail: SW
3 ft at 4 seconds and SE 3 ft at 10 seconds.
.WED...W winds 5 to 10 kt, becoming SW in the afternoon. Seas
3 to 4 ft. Wave Detail: SE 3 ft at 10 seconds and SW 2 ft at
4 seconds.
.WED NIGHT...SW winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: S
2 ft at 4 seconds and SE 2 ft at 9 seconds.
.THU...SW winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: S 2 ft
at 5 seconds and SE 2 ft at 9 seconds.
.THU NIGHT...S winds 10 to 15 kt with gusts to 20 kt. Seas 2 to
3 ft. Wave Detail: S 3 ft at 4 seconds and SE 2 ft at 9 seconds.
.FRI...SW winds 10 to 15 kt. Seas 2 to 3 ft.
.FRI NIGHT...SW winds 10 to 15 kt. Seas 3 ft. A slight chance of
showers and tstms.
.SAT...SW winds 10 to 15 kt. Seas 3 ft. A slight chance of
showers and tstms.
.SAT NIGHT...SW winds 15 kt. Seas 3 to 4 ft. A chance of showers
and tstms.

Winds and seas higher in and near tstms.

$$

AMZ384-182300-
Waters from Savannah GA to Altamaha Sound GA extending from 20 to
60 NM-
539 AM EDT Tue Aug 18 2026

.TODAY...W winds 10 to 15 kt with gusts to 20 kt, becoming SW
late. Seas 3 to 4 ft, subsiding to 2 to 3 ft this afternoon. Wave
Detail: SW 3 ft at 4 seconds and SE 2 ft at 8 seconds, becoming
SW 2 ft at 4 seconds and SE 2 ft at 9 seconds.
.TONIGHT...SW winds 10 to 15 kt. Seas 3 ft. Wave Detail: SW 3 ft
at 4 seconds and SE 2 ft at 10 seconds.
.WED...W winds 5 to 10 kt, becoming SW in the afternoon. Seas
2 to 3 ft. Wave Detail: SW 2 ft at 4 seconds and SE 2 ft at
10 seconds.
.WED NIGHT...SW winds 10 kt. Seas 2 to 3 ft. Wave Detail: S 2 ft
at 4 seconds and SE 2 ft at 9 seconds.
.THU...SW winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: S 2 ft
at 5 seconds and SE 2 ft at 9 seconds.
.THU NIGHT...S winds 10 to 15 kt with gusts to 20 kt. Seas 2 to
3 ft. Wave Detail: S 2 ft at 4 seconds and SE 2 ft at 8 seconds.
.FRI...SW winds 10 to 15 kt. Seas 2 to 3 ft.
.FRI NIGHT...SW winds 10 to 15 kt. Seas 2 to 3 ft. A chance of
showers and tstms.
.SAT...SW winds 10 to 15 kt. Seas 2 to 3 ft. A slight chance of
showers and tstms.
.SAT NIGHT...SW winds 15 kt. Seas 3 to 4 ft. A chance of showers
and tstms.

Winds and seas higher in and near tstms.

$$