944
FZUS52 KJAX 181633
CWFJAX

Coastal Waters Forecast for Northeast Florida/Southeast Georgia
National Weather Service Jacksonville FL
1233 PM EDT Mon Aug 18 2025

Atlantic Coastal Waters from Altamaha Sound GA to Flagler Beach
FL out to 60 nm.

Seas are provided as a range of the average height of the highest
1/3 of the waves, along with the occasional height of the average
highest 1/10 of the waves.

AMZ400-190700-
Synopsis for Altamaha Sound GA to Flagler Beach FL out to 60 nm-
1233 PM EDT Mon Aug 18 2025

.SYNOPSIS...

Weak troughing situated over the northeast Florida waters will shift
southward tonight as high pressure builds over New England and
wedges down the southeastern seaboard. This trough will increase the
coverage of showers and thunderstorms over the near shore waters
this morning, with a few waterspouts possible. Meanwhile, Major
Hurricane Erin will turn northwestward today and northward on
Tuesday, remaining well to the east of the Gulf Stream adjacent to
our local waters. Powerful ocean swells will enter our local waters
later this afternoon and tonight, with Small Craft Advisory
conditions beginning offshore this evening and near shore after
midnight. Breezy onshore winds and elevated, rough seas are expected
on Tuesday and Wednesday. Winds will shift to northwesterly and then
westerly on Wednesday night and Thursday as Erin turns north-
northeastward off the U.S. eastern seaboard. Seas are expected to
fall below Small Craft Advisory levels near shore on Friday morning,
while seas offshore gradually subside late on Friday night. Showers
and thunderstorms will likely increase in coverage on Friday as a
frontal boundary stalls over our region.


.GULF STREAM...

The approximate location of the west wall of the Gulf Stream as of
Aug 16, 2025 at 1200 UTC...

 57 nautical miles east of Flagler Beach.
 63 nautical miles east northeast of Saint Augustine Beach.
 68 nautical miles east of Jacksonville Beach.
 75 nautical miles east southeast of St Simons Island.

This data courtesy of the Naval Oceanographic Office.


$$

AMZ450-452-454-190700-
Coastal waters from Altamaha Sound to Fernandina Beach FL out
20 NM-
Coastal waters from Fernandina Beach to St. Augustine FL out
20 NM-
Coastal waters from St. Augustine to Flagler Beach FL out 20 NM-
1233 PM EDT Mon Aug 18 2025

...SMALL CRAFT ADVISORY IN EFFECT FROM LATE TONIGHT THROUGH
THURSDAY EVENING...

.REST OF TODAY...Northeast winds 10 to 15 knots. Seas 2 to
4 feet, occasionally to 5 feet. Wave Detail: Northeast 3 feet at
7 seconds and east 2 feet at 16 seconds. Intracoastal waters a
moderate chop. A chance of showers with a slight chance of
thunderstorms.
.TONIGHT...East winds 10 to 15 knots. Seas 4 to 6 feet,
occasionally to 8 feet. Wave Detail: East 5 feet at 14 seconds
and east 3 feet at 6 seconds. Intracoastal waters a moderate
chop. A slight chance of showers after midnight.
.TUESDAY...Northeast winds 15 to 20 knots. Seas 5 to 8 feet,
occasionally to 10 feet. Wave Detail: East 8 feet at 16 seconds
and northeast 4 feet at 6 seconds. Intracoastal waters choppy. A
chance of showers. A slight chance of thunderstorms in the
morning, then a chance of thunderstorms in the afternoon.
.TUESDAY NIGHT...Northeast winds 15 to 20 knots. Seas 7 to
10 feet, occasionally to 13 feet. Wave Detail: East 10 feet at
16 seconds and northeast 4 feet at 6 seconds. Intracoastal waters
choppy. A chance of showers. A chance of thunderstorms, mainly in
the evening.
.WEDNESDAY...North winds 15 to 20 knots. Seas 8 to 11 feet,
occasionally to 14 feet. Wave Detail: East 10 feet at 16 seconds
and northeast 4 feet at 6 seconds. Intracoastal waters choppy.
Showers likely with a slight chance of thunderstorms in the
morning, then a chance of showers and thunderstorms in the
afternoon.
.WEDNESDAY NIGHT...North winds around 10 knots, becoming
northwest after midnight. Seas 8 to 11 feet, occasionally to
14 feet, subsiding to 6 to 9 feet, occasionally to 11 feet after
midnight. Wave Detail: East 10 feet at 15 seconds and northeast
4 feet at 8 seconds, becoming east 9 feet at 15 seconds and
northeast 3 feet at 8 seconds. Intracoastal waters light chop. A
slight chance of showers and thunderstorms in the evening.
.THURSDAY...North winds 5 to 10 knots, becoming south. Seas 5 to
8 feet, occasionally to 10 feet. Intracoastal waters light chop.
A slight chance of showers and thunderstorms in the morning, then
a chance of showers and thunderstorms through the night. A slight
chance of showers and thunderstorms after midnight.
.FRIDAY...East winds 5 to 10 knots. Seas 5 to 7 feet,
occasionally to 9 feet. Intracoastal waters light chop. A chance
of showers and thunderstorms in the morning, then thunderstorms
likely in the afternoon. Showers likely through the night. A
chance of thunderstorms in the evening, then a chance of showers
with a slight chance of thunderstorms after midnight.

Winds and waves higher in and near thunderstorms.

$$

AMZ470-472-474-190700-
Waters from Altamaha Sound GA to Fernandina Beach FL from 20 to
60 NM-
Waters from Fernandina Beach to St. Augustine FL from 20 to 60 NM-
Waters from St. Augustine to Flagler Beach FL from 20 to 60 NM-
1233 PM EDT Mon Aug 18 2025

...SMALL CRAFT ADVISORY IN EFFECT FROM 8 PM EDT THIS EVENING
THROUGH THURSDAY EVENING...

.REST OF TODAY...Northeast winds 10 to 15 knots. Seas 3 to
5 feet, occasionally to 6 feet. Wave Detail: Northeast 4 feet at
8 seconds and southeast 4 feet at 15 seconds. A chance of showers
with a slight chance of thunderstorms.
.TONIGHT...East winds 10 to 15 knots. Seas 4 to 6 feet,
occasionally to 8 feet, building to 5 to 8 feet, occasionally to
10 feet after midnight. Wave Detail: East 5 feet at 14 seconds
and northeast 4 feet at 7 seconds, becoming east 7 feet at
16 seconds and east 3 feet at 6 seconds. A slight chance of
showers. A slight chance of thunderstorms after midnight.
.TUESDAY...Northeast winds 15 to 20 knots. Seas 8 to 11 feet,
occasionally to 14 feet. Wave Detail: East 9 feet at 16 seconds
and northeast 4 feet at 6 seconds. A chance of showers. A slight
chance of thunderstorms in the afternoon.
.TUESDAY NIGHT...Northeast winds 15 to 20 knots. Seas 9 to
13 feet, occasionally to 17 feet. Wave Detail: Southeast 12 feet
at 16 seconds and northeast 4 feet at 7 seconds. A chance of
thunderstorms. A chance of showers in the evening, then showers
likely after midnight.
.WEDNESDAY...North winds 15 to 20 knots. Seas 11 to 14 feet,
occasionally to 18 feet. Wave Detail: East 13 feet at 15 seconds
and northeast 5 feet at 7 seconds. A chance of thunderstorms.
Showers likely, mainly in the morning.
.WEDNESDAY NIGHT...Northwest winds 10 to 15 knots. Seas 9 to
13 feet, occasionally to 17 feet, subsiding to 8 to 10 feet,
occasionally to 13 feet after midnight. Wave Detail: East 11 feet
at 15 seconds and northeast 5 feet at 8 seconds, becoming east
10 feet at 14 seconds and northeast 4 feet at 8 seconds. A chance
of showers and thunderstorms.
.THURSDAY...North winds 10 to 15 knots, becoming southeast 5 to
10 knots. Seas 7 to 10 feet, occasionally to 13 feet. A chance of
showers and thunderstorms.
.FRIDAY...Northeast winds 5 to 10 knots, becoming east. Seas 5 to
8 feet, occasionally to 10 feet. A chance of thunderstorms. A
chance of showers in the morning, then showers likely.

Winds and seas higher in and near thunderstorms.

$$