549
FZCA52 TJSJ 181352
CWFSJU

Coastal Waters Forecast
National Weather Service San Juan PR
Issued by National Weather Service Brownsville TX
952 AM AST Tue Aug 18 2026

Puerto Rico and the U.S. Virgin Islands Waters

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 10 percent of the waves.

AMZ700-190300-
952 AM AST Tue Aug 18 2026

.Synopsis for Puerto Rico and the U.S. Virgin Islands Waters...

Light to moderate easterly trade winds will continue to
prevail across the region over the next few days. Seas peaking up to
5 feet today will gradually ease to 2 to 4 feet later in the
workweek. By late tonight into Wednesday, an approaching tropical
wave will draw in deep moisture, increasing the potential for
showers and thunderstorms across most local waters. This will
elevate localized lightning hazards and bring gusty winds over the
marine zones through midweek. Also, expect hazy skies across the
northeastern Caribbean due to suspended Saharan dust, with higher
concentrations after the wave passage.

$$

AMZ711-190300-
Atlantic Waters of Puerto Rico and USVI from 10 NM to 19.5N-
952 AM AST Tue Aug 18 2026

.REST OF TODAY...East winds 10 to 15 knots with gusts up to
20 knots. Seas 3 to 4 feet, occasionally to 5 feet. Wave Detail:
East 4 feet at 8 seconds. Isolated showers.
.TONIGHT...East winds 10 to 15 knots with gusts up to 20 knots. Seas
3 to 4 feet, occasionally to 5 feet. Wave Detail: East 4 feet at
8 seconds. Scattered showers after midnight.
.WEDNESDAY...East winds 10 to 15 knots with gusts up to 25 knots.
Seas 3 to 4 feet, occasionally to 5 feet. Wave Detail: East 4 feet
at 8 seconds. Scattered showers in the morning.
.WEDNESDAY NIGHT...East winds 10 to 15 knots, becoming southeast
15 to 20 knots after midnight. Seas 3 to 4 feet, occasionally to
5 feet. Wave Detail: East 4 feet at 8 seconds. Scattered showers in
the evening.
.THURSDAY...East winds 15 to 20 knots with gusts up to 30 knots.
Seas 3 to 5 feet, occasionally to 6 feet. Wave Detail: Southeast
4 feet at 5 seconds and east 4 feet at 8 seconds. Scattered showers
in the morning.
.THURSDAY NIGHT...East winds 15 to 20 knots with gusts up to
30 knots. Seas 4 to 5 feet, occasionally to 6 feet. Wave Detail:
East 4 feet at 7 seconds.
.FRIDAY...East winds around 15 knots. Seas 4 to 5 feet, occasionally
to 6 feet.
.FRIDAY NIGHT...East winds 15 to 20 knots. Seas 4 to 5 feet,
occasionally to 6 feet. Scattered showers.
.SATURDAY...East winds 10 to 15 knots. Seas 4 to 5 feet,
occasionally to 6 feet. Scattered showers in the morning.
.SATURDAY NIGHT...East winds around 15 knots. Seas 4 to 5 feet,
occasionally to 6 feet.

$$

AMZ712-190300-
Coastal Waters of Northern Puerto Rico out 10 NM-
952 AM AST Tue Aug 18 2026

.REST OF TODAY...East winds 5 to 10 knots, increasing to 10 to
15 knots with gusts up to 25 knots late this morning and afternoon.
Seas 3 to 4 feet, occasionally to 5 feet. Wave Detail: East 4 feet
at 8 seconds. Isolated showers.
.TONIGHT...East winds 10 to 15 knots with gusts up to 25 knots. Seas
3 to 4 feet, occasionally to 5 feet. Wave Detail: East 4 feet at
8 seconds. Scattered showers after midnight.
.WEDNESDAY...East winds 10 to 15 knots with gusts up to 25 knots.
Seas around 3 feet. Wave Detail: East 3 feet at 8 seconds. Scattered
showers.
.WEDNESDAY NIGHT...Southeast winds 10 to 15 knots with gusts up to
20 knots. Seas around 3 feet. Wave Detail: East 3 feet at 8 seconds.
Scattered showers.
.THURSDAY...East winds 10 to 15 knots with gusts up to 20 knots,
increasing to 15 to 20 knots with gusts up to 30 knots in the
afternoon. Seas 3 to 4 feet, occasionally to 5 feet. Wave Detail:
East 4 feet at 5 seconds and northeast 4 feet at 8 seconds. Numerous
showers in the morning.
.THURSDAY NIGHT...East winds 15 to 20 knots with gusts up to
30 knots, diminishing to 10 to 15 knots with gusts up to 20 knots
after midnight. Seas 4 to 5 feet, occasionally to 6 feet. Wave
Detail: Northeast 4 feet at 7 seconds.
.FRIDAY...East winds 10 to 15 knots, increasing to 15 to 20 knots in
the afternoon. Seas 4 to 5 feet, occasionally to 6 feet.
.FRIDAY NIGHT...East winds 15 to 20 knots, diminishing to 10 to
15 knots after midnight. Seas 4 to 5 feet, occasionally to 6 feet.
Scattered showers.
.SATURDAY...East winds 10 to 15 knots, increasing to 15 to 20 knots
in the afternoon. Seas 4 to 5 feet, occasionally to 6 feet.
.SATURDAY NIGHT...East winds 15 to 20 knots, diminishing to 10 to
15 knots after midnight. Seas 4 to 5 feet, occasionally to 6 feet.

$$

AMZ716-190300-
Coastal Waters from Cabo San Juan to the waters between Anegada
Island and Virgin Gorda and North 10 NM-
952 AM AST Tue Aug 18 2026

.REST OF TODAY...East winds 10 to 15 knots with gusts up to
20 knots. Seas 2 to 3 feet. Wave Detail: East 2 feet at 4 seconds
and northeast 2 feet at 8 seconds. Isolated showers.
.TONIGHT...East winds around 15 knots with gusts up to 20 knots.
Seas 2 to 3 feet. Wave Detail: East 3 feet at 4 seconds and east
2 feet at 8 seconds. Numerous showers after midnight.
.WEDNESDAY...Southeast winds 10 to 15 knots with gusts up to
20 knots. Seas 2 to 3 feet. Wave Detail: Southeast 3 feet at
5 seconds and east 2 feet at 8 seconds. Numerous showers, mainly in
the morning.
.WEDNESDAY NIGHT...East winds 10 to 15 knots, increasing to 15 to
20 knots after midnight. Seas 2 to 3 feet. Wave Detail: East 3 feet
at 4 seconds and northeast 2 feet at 8 seconds. Scattered showers in
the evening.
.THURSDAY...East winds around 15 knots with gusts up to 25 knots.
Seas 3 to 4 feet, occasionally to 5 feet. Wave Detail: East 4 feet
at 5 seconds and northeast 1 foot at 8 seconds. Scattered showers in
the morning.
.THURSDAY NIGHT...East winds around 15 knots with gusts up to
25 knots. Seas 3 to 4 feet, occasionally to 5 feet. Wave Detail:
Northeast 3 feet at 7 seconds.
.FRIDAY...East winds around 15 knots. Seas 3 to 4 feet, occasionally
to 5 feet. Scattered showers in the afternoon.
.FRIDAY NIGHT...East winds around 15 knots. Seas 3 to 4 feet,
occasionally to 5 feet. Scattered showers.
.SATURDAY...East winds around 15 knots. Seas 3 to 4 feet,
occasionally to 5 feet.
.SATURDAY NIGHT...East winds around 15 knots. Seas 3 to 4 feet,
occasionally to 5 feet.

$$

AMZ723-190300-
Anegada Passage east of Virgin Gorda and Saint Croix south to 17N-
952 AM AST Tue Aug 18 2026

.REST OF TODAY...East winds 10 to 15 knots with gusts up to
20 knots. Seas 3 to 4 feet, occasionally to 5 feet. Wave Detail:
East 3 feet at 5 seconds and east 3 feet at 9 seconds. Isolated
showers early this morning, then scattered showers this afternoon.
.TONIGHT...East winds 10 to 15 knots with gusts up to 20 knots. Seas
3 to 4 feet, occasionally to 5 feet. Wave Detail: East 3 feet at
5 seconds and east 3 feet at 8 seconds. Scattered showers in the
evening, then numerous showers after midnight.
.WEDNESDAY...Southeast winds 10 to 15 knots with gusts up to
20 knots. Seas 2 to 4 feet, occasionally to 5 feet. Wave Detail:
East 3 feet at 8 seconds and southeast 2 feet at 5 seconds.
Scattered showers.
.WEDNESDAY NIGHT...East winds 10 to 15 knots, increasing to 15 to
20 knots after midnight. Seas 3 to 4 feet, occasionally to 5 feet.
Wave Detail: East 4 feet at 5 seconds and east 2 feet at 8 seconds.
Scattered showers in the evening.
.THURSDAY...East winds 15 to 20 knots with gusts up to 25 knots.
Seas 4 to 5 feet, occasionally to 6 feet. Wave Detail: Northeast
5 feet at 7 seconds.
.THURSDAY NIGHT...East winds 15 to 20 knots with gusts up to
25 knots. Seas 4 to 5 feet, occasionally to 6 feet. Wave Detail:
East 4 feet at 7 seconds.
.FRIDAY...East winds 15 to 20 knots. Seas around 4 feet,
occasionally to 5 feet.
.FRIDAY NIGHT...East winds 15 to 20 knots. Seas 4 to 5 feet,
occasionally to 6 feet. Scattered showers.
.SATURDAY...East winds 15 to 20 knots. Seas around 4 feet,
occasionally to 5 feet.
.SATURDAY NIGHT...East winds around 15 knots. Seas 4 to 5 feet,
occasionally to 6 feet.

$$

AMZ726-190300-
Coastal waters east of Puerto Rico, around Vieques, and around and
just north of Culebra and Saint John-
952 AM AST Tue Aug 18 2026

.REST OF TODAY...East winds 10 to 15 knots with gusts up to
20 knots. Seas 3 to 4 feet, occasionally to 5 feet. Wave Detail:
East 3 feet at 8 seconds and east 2 feet at 5 seconds. Isolated
showers early this morning, then scattered showers late.
.TONIGHT...East winds 10 to 15 knots with gusts up to 20 knots. Seas
around 3 feet. Wave Detail: East 3 feet at 5 seconds and east 3 feet
at 8 seconds. Scattered showers in the evening, then numerous
showers after midnight.
.WEDNESDAY...Southeast winds 10 to 15 knots with gusts up to
20 knots. Seas 2 to 3 feet. Wave Detail: East 3 feet at 8 seconds
and southeast 2 feet at 5 seconds. Numerous showers, mainly in the
morning.
.WEDNESDAY NIGHT...East winds 10 to 15 knots, increasing to 15 to
20 knots after midnight. Seas 2 to 3 feet. Wave Detail: Southeast
3 feet at 4 seconds and east 3 feet at 8 seconds. Scattered showers
in the evening.
.THURSDAY...East winds 15 to 20 knots with gusts up to 25 knots.
Seas 3 to 4 feet, occasionally to 5 feet. Wave Detail: East 4 feet
at 5 seconds and east 1 foot at 8 seconds. Scattered showers in the
morning.
.THURSDAY NIGHT...East winds 15 to 20 knots with gusts up to
25 knots. Seas 3 to 4 feet, occasionally to 5 feet. Wave Detail:
East 4 feet at 6 seconds.
.FRIDAY...East winds around 15 knots. Seas 3 to 4 feet, occasionally
to 5 feet.
.FRIDAY NIGHT...East winds around 15 knots. Seas 3 to 4 feet,
occasionally to 5 feet. Scattered showers.
.SATURDAY...East winds around 15 knots. Seas 3 to 4 feet,
occasionally to 5 feet.
.SATURDAY NIGHT...East winds around 15 knots. Seas 3 to 4 feet,
occasionally to 5 feet.

$$

AMZ733-190300-
Caribbean waters of Puerto Rico from 10 NM to 17N, including the
coastal waters of Saint Croix-
952 AM AST Tue Aug 18 2026

.REST OF TODAY...East winds around 15 knots with gusts up to
25 knots. Seas 3 to 4 feet, occasionally to 5 feet. Wave Detail:
East 4 feet at 7 seconds. Isolated showers early this morning, then
scattered showers this afternoon.
.TONIGHT...East winds around 15 knots with gusts up to 25 knots.
Seas 3 to 4 feet, occasionally to 5 feet. Wave Detail: East 4 feet
at 7 seconds. Scattered showers in the evening, then numerous
showers after midnight.
.WEDNESDAY...Southeast winds 10 to 15 knots with gusts up to
25 knots. Seas around 3 feet. Wave Detail: East 3 feet at 7 seconds.
Scattered showers.
.WEDNESDAY NIGHT...East winds 10 to 15 knots, increasing to 15 to
20 knots after midnight. Seas 3 to 4 feet, occasionally to 5 feet.
Wave Detail: East 4 feet at 5 seconds and east 1 foot at 8 seconds.
Scattered showers in the evening.
.THURSDAY...East winds 15 to 20 knots with gusts up to 25 knots.
Seas 4 to 5 feet, occasionally to 6 feet. Wave Detail: East 5 feet
at 7 seconds. Scattered showers in the morning.
.THURSDAY NIGHT...East winds 15 to 20 knots with gusts up to
25 knots. Seas 4 to 5 feet, occasionally to 6 feet. Wave Detail:
East 5 feet at 6 seconds.
.FRIDAY...East winds 15 to 20 knots. Seas 4 to 6 feet, occasionally
to 8 feet.
.FRIDAY NIGHT...East winds 15 to 20 knots. Seas 4 to 5 feet,
occasionally to 6 feet.
.SATURDAY...East winds 15 to 20 knots. Seas 4 to 5 feet,
occasionally to 6 feet.
.SATURDAY NIGHT...East winds 15 to 20 knots. Seas 4 to 5 feet,
occasionally to 6 feet.

$$

AMZ735-190300-
Coastal Waters of Southern Puerto Rico out 10 NM-
952 AM AST Tue Aug 18 2026

.REST OF TODAY...East winds 5 to 10 knots, increasing to 10 to
15 knots late this morning and afternoon. Gusts up to 25 knots. Seas
2 to 3 feet. Wave Detail: East 3 feet at 6 seconds. Isolated
showers.
.TONIGHT...East winds 10 to 15 knots with gusts up to 25 knots. Seas
2 to 4 feet, occasionally to 5 feet. Wave Detail: East 3 feet at
5 seconds. Scattered showers after midnight.
.WEDNESDAY...Southeast winds 10 to 15 knots with gusts up to
20 knots. Seas 2 to 3 feet. Wave Detail: East 3 feet at 7 seconds.
Scattered showers.
.WEDNESDAY NIGHT...East winds 10 to 15 knots with gusts up to
20 knots. Seas 2 to 3 feet. Wave Detail: East 3 feet at 5 seconds
and east 1 foot at 8 seconds.
.THURSDAY...East winds 15 to 20 knots with gusts up to 25 knots.
Seas 3 to 4 feet, occasionally to 5 feet. Wave Detail: East 4 feet
at 5 seconds and east 1 foot at 8 seconds. Scattered showers in the
morning.
.THURSDAY NIGHT...East winds 15 to 20 knots with gusts up to
25 knots. Seas 3 to 5 feet, occasionally to 6 feet. Wave Detail:
Southeast 4 feet at 6 seconds.
.FRIDAY...East winds 15 to 20 knots. Seas 3 to 5 feet, occasionally
to 6 feet.
.FRIDAY NIGHT...East winds 10 to 15 knots. Seas 3 to 4 feet,
occasionally to 5 feet.
.SATURDAY...East winds 10 to 15 knots. Seas 3 to 4 feet,
occasionally to 5 feet.
.SATURDAY NIGHT...East winds 10 to 15 knots. Seas 3 to 4 feet,
occasionally to 5 feet.

$$

AMZ741-190300-
Mona Passage Southward to 17N-
952 AM AST Tue Aug 18 2026

.REST OF TODAY...East winds 10 to 15 knots with gusts up to
20 knots. Seas 3 to 4 feet, occasionally to 5 feet. Wave Detail:
East 4 feet at 6 seconds and northeast 1 foot at 9 seconds. Isolated
showers this afternoon.
.TONIGHT...East winds 10 to 15 knots with gusts up to 25 knots. Seas
3 to 4 feet, occasionally to 5 feet. Wave Detail: East 4 feet at
7 seconds. Scattered showers after midnight.
.WEDNESDAY...East winds 15 to 20 knots, becoming southeast 10 to
15 knots in the afternoon. Seas 3 to 4 feet, occasionally to 5 feet.
Wave Detail: East 4 feet at 6 seconds. Scattered showers in the
morning.
.WEDNESDAY NIGHT...East winds 10 to 15 knots with gusts up to
25 knots. Seas 3 to 4 feet, occasionally to 5 feet. Wave Detail:
Southeast 4 feet at 5 seconds and northeast 1 foot at 8 seconds.
.THURSDAY...East winds 15 to 20 knots with gusts up to 25 knots.
Seas 3 to 5 feet, occasionally to 6 feet. Wave Detail: East 5 feet
at 7 seconds. Scattered showers.
.THURSDAY NIGHT...East winds 15 to 20 knots with gusts up to
25 knots. Seas 3 to 5 feet, occasionally to 6 feet. Wave Detail:
Southeast 5 feet at 6 seconds and northeast 1 foot at 8 seconds.
Scattered showers in the evening.
.FRIDAY...East winds 15 to 20 knots. Seas 4 to 6 feet, occasionally
to 8 feet. Scattered showers in the afternoon.
.FRIDAY NIGHT...East winds 15 to 20 knots. Seas 4 to 6 feet,
occasionally to 8 feet.
.SATURDAY...East winds 15 to 20 knots, diminishing to 10 to 15 knots
in the afternoon. Seas 4 to 6 feet, occasionally to 8 feet.
Scattered showers in the morning.
.SATURDAY NIGHT...East winds 15 to 20 knots. Seas 4 to 5 feet,
occasionally to 6 feet.

$$

AMZ742-190300-
Coastal Waters of Northwestern Puerto Rico out 10 NM-
952 AM AST Tue Aug 18 2026

.REST OF TODAY...Northeast winds 5 to 10 knots, becoming northeast
5 to 10 knots with gusts up to 20 knots this afternoon. Seas 2 to
3 feet. Wave Detail: Northeast 2 feet at 9 seconds and east 1 foot
at 5 seconds. Isolated showers early this afternoon. Scattered
showers late.
.TONIGHT...East winds 10 to 15 knots with gusts up to 20 knots. Seas
2 to 3 feet. Wave Detail: East 2 feet at 5 seconds and northeast
2 feet at 8 seconds.
.WEDNESDAY...East winds 5 to 10 knots, diminishing to around 5 knots
in the afternoon. Seas 2 to 3 feet. Wave Detail: Northeast 2 feet at
5 seconds and northeast 1 foot at 8 seconds. Numerous showers in the
afternoon.
.WEDNESDAY NIGHT...East winds 5 to 10 knots. Seas around 2 feet.
Wave Detail: Southeast 2 feet at 4 seconds and northeast 1 foot at
8 seconds. Scattered showers.
.THURSDAY...East winds 5 to 10 knots. Seas 2 to 3 feet. Wave Detail:
South 1 foot at 5 seconds and northeast 1 foot at 8 seconds.
Scattered showers in the afternoon.
.THURSDAY NIGHT...East winds 5 to 10 knots with gusts up to
20 knots. Seas 2 to 3 feet. Wave Detail: North 3 feet at 7 seconds.
Scattered showers in the evening.
.FRIDAY...Northeast winds 5 to 10 knots. Seas 2 to 3 feet. Scattered
showers in the afternoon.
.FRIDAY NIGHT...East winds 10 to 15 knots. Seas 2 to 4 feet,
occasionally to 5 feet.
.SATURDAY...East winds 10 to 15 knots, diminishing to 5 to 10 knots
in the afternoon. Seas 2 to 3 feet. Numerous showers in the
afternoon.
.SATURDAY NIGHT...East winds 10 to 15 knots. Seas 2 to 4 feet,
occasionally to 5 feet.

$$

AMZ745-190300-
Coastal Waters of Southwestern Puerto Rico out 10 NM-
952 AM AST Tue Aug 18 2026

.REST OF TODAY...East winds around 5 knots, becoming south early
this afternoon, then becoming north late. Seas around 2 feet. Wave
Detail: North 1 foot at 4 seconds and southeast 1 foot at 5 seconds.
Isolated showers early this afternoon. Scattered showers late.
.TONIGHT...East winds 5 to 10 knots. Seas around 2 feet. Wave
Detail: North 1 foot at 4 seconds and southeast 1 foot at 5 seconds.
.WEDNESDAY...Southeast winds 10 to 15 knots with gusts up to
25 knots. Seas around 2 feet. Wave Detail: Southeast 2 feet at
3 seconds and north 1 foot at 4 seconds. Scattered showers in the
afternoon.
.WEDNESDAY NIGHT...East winds 10 to 15 knots with gusts up to
20 knots. Seas around 2 feet. Wave Detail: Southeast 2 feet at
4 seconds.
.THURSDAY...East winds 10 to 15 knots with gusts up to 25 knots.
Seas 2 to 3 feet. Wave Detail: Southeast 2 feet at 5 seconds and
north 1 foot at 6 seconds. Scattered showers in the afternoon.
.THURSDAY NIGHT...East winds 10 to 15 knots with gusts up to
25 knots. Seas 2 to 3 feet. Wave Detail: Southeast 3 feet at
6 seconds and north 1 foot at 7 seconds.
.FRIDAY...East winds 5 to 10 knots, becoming southeast in the
afternoon. Seas 2 to 3 feet.
.FRIDAY NIGHT...East winds 5 to 10 knots. Seas 2 to 3 feet.
.SATURDAY...East winds 5 to 10 knots. Seas 2 to 3 feet. Scattered
showers in the afternoon.
.SATURDAY NIGHT...East winds 5 to 10 knots. Seas 2 to 3 feet.

$$