926
FZUS52 KCHS 210550
CWFCHS

Coastal Waters Forecast
National Weather Service Charleston SC
150 AM EDT Thu Aug 21 2025

South Santee River SC to Savannah GA out 20 NM and Savannah GA to
Altamaha Sound GA out 60 NM, including Charleston Harbor and
Grays Reef National Marine Sanctuary

AMZ300-211800-
150 AM EDT Thu Aug 21 2025

.Synopsis for the coastal waters of south coastal South Carolina
and north coastal Georgia...
Weak high pressure will continue to build into the region as
Hurricane Erin passes well offshore. The pattern may become more
unsettled again late week and into this weekend as cold front
stalls nearby.

$$

AMZ330-211800-
Charleston Harbor-
150 AM EDT Thu Aug 21 2025

.REST OF TONIGHT...NW winds 5 to 10 kt.
.THU...NW winds 5 to 10 kt. A slight chance of showers and tstms
in the afternoon.
.THU NIGHT...SW winds 5 kt. A chance of showers and tstms.
.FRI...NE winds 5 to 10 kt, becoming E 10 to 15 kt in the
afternoon. A chance of showers and tstms.
.FRI NIGHT...E winds 5 to 10 kt. A chance of showers and tstms.
.SAT...E winds 5 to 10 kt. Showers likely. A chance of tstms in
the morning, then tstms likely in the afternoon.
.SAT NIGHT...E winds 5 to 10 kt. A chance of tstms. Showers
likely, mainly in the evening.
.SUN...NE winds 5 to 10 kt. Showers likely with a chance of
tstms.
.SUN NIGHT...SW winds 5 kt. A chance of showers and tstms.
.MON...W winds 5 to 10 kt. A chance of showers and tstms.
.MON NIGHT...W winds 5 to 10 kt.

Winds and waves higher in and near tstms.

Unless otherwise noted, waves 1 foot or less.

Charleston Harbor water temperature 85 degrees.

$$

AMZ350-211800-
Waters from South Santee River to Edisto Beach SC out 20 NM-
150 AM EDT Thu Aug 21 2025

...SMALL CRAFT ADVISORY IN EFFECT THROUGH THIS AFTERNOON...

.REST OF TONIGHT...NW winds 10 to 15 kt with gusts to 20 kt. Seas
6 to 8 ft. Wave Detail: SE 8 ft at 8 seconds and SE 8 ft at
16 seconds.
.THU...NW winds 10 to 15 kt with gusts to 20 kt, becoming W 5 to
10 kt in the afternoon. Seas 4 to 6 ft, subsiding to 4 to 5 ft in
the afternoon. Wave Detail: SE 6 ft at 8 seconds and SE 6 ft at
15 seconds, becoming E 5 ft at 13 seconds.
.THU NIGHT...SW winds 5 to 10 kt. Seas 3 to 4 ft. Wave Detail: E
4 ft at 12 seconds. A chance of showers and tstms.
.FRI...NE winds 10 to 15 kt. Seas 2 to 3 ft. Wave Detail: E 3 ft
at 4 seconds and E 3 ft at 12 seconds. Showers and tstms likely.
.FRI NIGHT...E winds 10 to 15 kt. Seas 3 to 4 ft. Wave Detail: E
4 ft at 13 seconds and E 3 ft at 4 seconds. A chance of showers
and tstms.
.SAT...E winds 10 to 15 kt. Seas 3 to 4 ft, building to 4 to 5 ft
in the afternoon. Wave Detail: E 4 ft at 13 seconds and SE 1 foot
at 8 seconds, becoming E 3 ft at 6 seconds and E 3 ft at
13 seconds. Showers and tstms likely.
.SAT NIGHT...E winds 10 to 15 kt, diminishing to 5 to 10 kt after
midnight. Seas 4 to 5 ft, subsiding to 3 to 4 ft after midnight.
Showers likely with a chance of tstms.
.SUN...NE winds 5 to 10 kt. Seas 2 to 3 ft. Showers likely with a
chance of tstms.
.SUN NIGHT...SW winds 5 to 10 kt. Seas 2 to 3 ft. A chance of
showers and tstms.
.MON...W winds 5 to 10 kt. Seas 2 ft. A chance of showers with a
slight chance of tstms.
.MON NIGHT...W winds 10 kt. Seas 2 to 3 ft. A slight chance of
showers and tstms.

Winds and seas higher in and near tstms.

$$

AMZ352-211800-
Waters from Edisto Beach SC to Savannah GA out 20 NM-
150 AM EDT Thu Aug 21 2025

...SMALL CRAFT ADVISORY IN EFFECT THROUGH THIS AFTERNOON...

.REST OF TONIGHT...NW winds 10 kt. Seas 4 to 6 ft. Wave Detail:
SE 6 ft at 8 seconds and SE 6 ft at 16 seconds.
.THU...NW winds 5 to 10 kt, becoming SW in the afternoon. Seas
4 to 5 ft, subsiding to 3 to 4 ft in the afternoon. Wave Detail:
SE 5 ft at 8 seconds and SE 5 ft at 15 seconds, becoming SE 4 ft
at 7 seconds and E 4 ft at 15 seconds.
.THU NIGHT...SW winds 5 kt. Seas 3 to 4 ft. Wave Detail: E 4 ft
at 12 seconds. A chance of tstms. A chance of showers in the
evening, then showers likely after midnight.
.FRI...NE winds 5 to 10 kt, becoming E 10 to 15 kt in the
afternoon. Seas 2 to 3 ft. Wave Detail: E 3 ft at 12 seconds.
Showers and tstms likely.
.FRI NIGHT...E winds 10 to 15 kt, diminishing to 5 to 10 kt after
midnight. Seas 3 to 4 ft. Wave Detail: E 4 ft at 12 seconds.
Showers likely. Tstms likely, mainly in the evening.
.SAT...E winds 5 to 10 kt. Seas 3 to 4 ft. Wave Detail: E 4 ft at
13 seconds and S 1 foot at 4 seconds. Showers. A chance of tstms
in the morning, then tstms likely in the afternoon.
.SAT NIGHT...E winds 5 to 10 kt. Seas 4 to 5 ft, subsiding to
3 to 4 ft after midnight. Showers likely. Tstms likely, mainly in
the evening.
.SUN...NE winds 5 to 10 kt. Seas 2 to 3 ft. Showers likely with a
chance of tstms.
.SUN NIGHT...SW winds 5 kt. Seas 2 to 3 ft. A chance of showers
and tstms.
.MON...W winds 5 to 10 kt. Seas 2 ft. A chance of showers and
tstms.
.MON NIGHT...W winds 5 to 10 kt. Seas 2 ft. A slight chance of
showers and tstms.

Winds and seas higher in and near tstms.

$$

AMZ354-211800-
Waters from Savannah GA to Altamaha Sound GA out 20 NM, including
Grays Reef National Marine Sanctuary-
150 AM EDT Thu Aug 21 2025

.REST OF TONIGHT...NW winds 10 kt. Seas 4 to 5 ft. Wave Detail: E
5 ft at 8 seconds and SE 5 ft at 16 seconds.
.THU...NW winds 5 to 10 kt, becoming SE in the afternoon. Seas
3 to 4 ft. Wave Detail: E 4 ft at 8 seconds and E 4 ft at
15 seconds. A slight chance of showers and tstms in the
afternoon.
.THU NIGHT...S winds 5 to 10 kt, becoming SW after midnight. Seas
3 to 4 ft. Wave Detail: E 4 ft at 13 seconds. A chance of tstms.
Showers likely, mainly in the evening.
.FRI...N winds 5 to 10 kt, becoming E in the afternoon. Seas 2 to
3 ft. Wave Detail: E 3 ft at 12 seconds. Showers likely. A chance
of tstms in the morning, then tstms likely in the afternoon.
.FRI NIGHT...E winds 10 to 15 kt, diminishing to 5 to 10 kt after
midnight. Seas 3 to 4 ft. Wave Detail: E 4 ft at 12 seconds.
Showers. Tstms likely, mainly in the evening.
.SAT...E winds 10 kt. Seas 3 to 4 ft. Wave Detail: E 4 ft at
13 seconds. Showers. A chance of tstms in the morning, then tstms
likely in the afternoon.
.SAT NIGHT...E winds 10 kt, becoming S after midnight. Seas 3 to
4 ft. A chance of tstms. Showers.
.SUN...N winds 5 to 10 kt. Seas 2 to 3 ft. Showers and tstms
likely.
.SUN NIGHT...W winds 5 to 10 kt. Seas 2 to 3 ft. A chance of
showers and tstms.
.MON...W winds 5 to 10 kt. Seas 2 to 3 ft. A chance of showers
and tstms.
.MON NIGHT...SW winds 5 to 10 kt. Seas 2 ft. A slight chance of
showers and tstms.

Winds and seas higher in and near tstms.

$$

AMZ374-211800-
Waters from Savannah GA to Altamaha Sound GA from 20 to 60 NM-
150 AM EDT Thu Aug 21 2025

...SMALL CRAFT ADVISORY IN EFFECT THROUGH FRIDAY MORNING...

.REST OF TONIGHT...NW winds 10 kt. Seas 6 to 8 ft. Wave Detail: E
8 ft at 16 seconds.
.THU...NW winds 5 to 10 kt. Seas 5 to 7 ft. Wave Detail: E 7 ft
at 15 seconds.
.THU NIGHT...S winds 5 to 10 kt, becoming SW after midnight. Seas
5 to 7 ft, subsiding to 4 to 6 ft after midnight. Wave Detail: E
7 ft at 12 seconds, becoming E 6 ft at 12 seconds. A chance of
showers and tstms.
.FRI...N winds 5 to 10 kt, becoming E in the afternoon. Seas 4 to
5 ft. Wave Detail: E 5 ft at 12 seconds. Showers likely. A chance
of tstms in the morning, then tstms likely in the afternoon.
.FRI NIGHT...E winds 5 to 10 kt. Seas 4 to 5 ft. Wave Detail: E
5 ft at 12 seconds and SE 1 foot at 8 seconds. Showers. Tstms
likely, mainly in the evening.
.SAT...E winds 5 to 10 kt. Seas 4 to 5 ft. Wave Detail: E 5 ft at
13 seconds and SE 1 foot at 8 seconds. Showers with a chance of
tstms.
.SAT NIGHT...E winds 10 kt, becoming SW after midnight. Seas 4 to
5 ft. A chance of tstms. Showers.
.SUN...NW winds 5 to 10 kt. Seas 4 to 5 ft. Showers likely with a
chance of tstms.
.SUN NIGHT...W winds 5 to 10 kt. Seas 3 to 4 ft. Showers likely
with a chance of tstms.
.MON...W winds 5 to 10 kt. Seas 3 to 4 ft. A chance of showers
and tstms.
.MON NIGHT...SW winds 5 to 10 kt. Seas 2 to 3 ft. A chance of
showers with a slight chance of tstms.

Winds and seas higher in and near tstms.

$$