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National Weather Service Marine Forecast FZCA52 TJSJ

FZCA52 TJSJ 120844
CWFSJU

Coastal Waters Forecast
National Weather Service San Juan PR
444 AM AST Mon May 12 2025

Puerto Rico and the U.S. Virgin Islands Waters

AMZ700-122115
444 AM AST Mon May 12 2025

SYNOPSIS FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS WATERS

A broad surface high pressure over the Central Atlantic will sink southward over the next few days, resulting in increasing winds and choppy conditions across the offshore waters. A Small Craft Advisory is now in effect for the Atlantic offshore waters and the Anegada Passage due to seas building up to 7 feet by this afternoon. Small Craft Should Exercise Caution over most of the other waters. Thunderstorm activity is likely across the regional waters, especially in the afternoons and evenings, resulting in locally higher winds and seas.


AMZ711-122115
Atlantic Waters of Puerto Rico and USVI from 10 NM to 19.5N
444 AM AST Mon May 12 2025

SMALL CRAFT SHOULD EXERCISE CAUTION THROUGH NOON AST TODAY

SMALL CRAFT ADVISORY IN EFFECT FROM NOON AST TODAY THROUGH LATE TONIGHT

TODAY
East winds 15 to 20 knots with gusts up to 25 knots. Seas 5 to 7 feet, occasionally to 9 feet. Wave Detail: East 6 feet at 8 seconds. Isolated showers this morning. Scattered showers early this afternoon, then isolated showers late.

TONIGHT
East winds 15 to 20 knots with gusts up to 30 knots. Seas 6 to 7 feet, occasionally to 9 feet. Wave Detail: East 6 feet at 8 seconds.

TUESDAY
East winds 15 to 20 knots with gusts up to 30 knots. Seas around 6 feet, occasionally to 8 feet. Wave Detail: East 6 feet at 8 seconds.

TUESDAY NIGHT
East winds 15 to 20 knots with gusts up to 25 knots. Seas 5 to 6 feet, occasionally to 8 feet. Wave Detail: East 6 feet at 8 seconds.

WEDNESDAY
East winds 15 to 20 knots with gusts up to 25 knots. Seas 5 to 6 feet, occasionally to 8 feet. Wave Detail: East 6 feet at 8 seconds.

WEDNESDAY NIGHT
East winds 15 to 20 knots with gusts up to 30 knots. Seas 5 to 6 feet, occasionally to 8 feet. Wave Detail: East 6 feet at 8 seconds.

THURSDAY
East winds 15 to 20 knots. Seas 5 to 6 feet, occasionally to 8 feet.

THURSDAY NIGHT
East winds 15 to 20 knots. Seas around 5 feet, occasionally to 6 feet.

FRIDAY
East winds 15 to 20 knots. Seas 4 to 5 feet, occasionally to 6 feet. Scattered showers in the morning.

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.


AMZ712-122115
Coastal Waters of Northern Puerto Rico out 10 NM
444 AM AST Mon May 12 2025

SMALL CRAFT SHOULD EXERCISE CAUTION

TODAY
East winds 10 to 15 knots with gusts up to 20 knots, increasing to 15 to 20 knots with gusts up to 30 knots this afternoon. Seas 4 to 5 feet, occasionally to 6 feet. Wave Detail: Northeast 5 feet at 8 seconds. Isolated showers this morning. Scattered showers early this afternoon, then isolated showers late.

TONIGHT
East winds 15 to 20 knots with gusts up to 25 knots. Seas 5 to 6 feet, occasionally to 8 feet. Wave Detail: Northeast 5 feet at 8 seconds and northeast 1 foot at 12 seconds.

TUESDAY
East winds 15 to 20 knots with gusts up to 25 knots. Seas 5 to 6 feet, occasionally to 8 feet. Wave Detail: Northeast 6 feet at 8 seconds. Scattered showers in the afternoon.

TUESDAY NIGHT
East winds 15 to 20 knots, diminishing to 10 to 15 knots after midnight. Seas 4 to 6 feet, occasionally to 8 feet. Wave Detail: Northeast 5 feet at 8 seconds.

WEDNESDAY
East winds 10 to 15 knots with gusts up to 25 knots. Seas 4 to 5 feet, occasionally to 6 feet. Wave Detail: Northeast 5 feet at 7 seconds. Scattered showers in the afternoon.

WEDNESDAY NIGHT
East winds 10 to 15 knots with gusts up to 25 knots. Seas 4 to 5 feet, occasionally to 6 feet. Wave Detail: East 5 feet at 8 seconds.

THURSDAY
East winds 10 to 15 knots. Seas 4 to 5 feet, occasionally to 6 feet. Scattered showers.

THURSDAY NIGHT
East winds 10 to 15 knots, diminishing to 5 to 10 knots after midnight. Seas 4 to 5 feet, occasionally to 6 feet.

FRIDAY
East winds 5 to 10 knots. Seas around 4 feet, occasionally to 5 feet. Scattered showers in the morning, then numerous showers in the afternoon.

FRIDAY NIGHT
East winds 10 to 15 knots, diminishing to 5 to 10 knots after midnight. Seas 3 to 4 feet, occasionally to 5 feet.


AMZ716-122115
Coastal Waters from Cabo San Juan to the waters between Anegada Island and Virgin Gorda and North 10 NM
444 AM AST Mon May 12 2025

SMALL CRAFT SHOULD EXERCISE CAUTION

TODAY
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. Isolated showers this morning, then scattered showers early this afternoon. Isolated showers late.

TONIGHT
East winds 15 to 20 knots with gusts up to 25 knots. Seas 4 to 6 feet, occasionally to 8 feet. Wave Detail: East 5 feet at 8 seconds.

TUESDAY
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 8 seconds. Scattered showers in the afternoon.

TUESDAY 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 7 seconds.

WEDNESDAY
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. Scattered showers in the afternoon.

WEDNESDAY NIGHT
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 6 seconds. Scattered showers.

THURSDAY
East winds 15 to 20 knots. Seas 3 to 5 feet, occasionally to 6 feet.

THURSDAY NIGHT
East winds 15 to 20 knots. Seas 3 to 4 feet, occasionally to 5 feet.

FRIDAY
East winds 15 to 20 knots, diminishing to 10 to 15 knots in the afternoon. Seas 3 to 5 feet, occasionally to 6 feet. Scattered showers in the morning, then numerous showers in the afternoon.

FRIDAY NIGHT
East winds 5 to 10 knots. Seas 2 to 4 feet, occasionally to 5 feet. Scattered showers.


AMZ723-122115
Anegada Passage east of Virgin Gorda and Saint Croix south to 17N
444 AM AST Mon May 12 2025

SMALL CRAFT SHOULD EXERCISE CAUTION THROUGH NOON AST TODAY

SMALL CRAFT ADVISORY IN EFFECT FROM NOON AST TODAY THROUGH LATE TONIGHT

TODAY
East winds 15 to 20 knots with gusts up to 25 knots. Seas 6 to 7 feet, occasionally to 9 feet. Wave Detail: East 6 feet at 7 seconds. Isolated showers.

TONIGHT
East winds 15 to 20 knots with gusts up to 25 knots. Seas 6 to 7 feet, occasionally to 9 feet. Wave Detail: East 6 feet at 8 seconds.

TUESDAY
East winds 15 to 20 knots with gusts up to 25 knots. Seas 5 to 6 feet, occasionally to 8 feet. Wave Detail: East 6 feet at 7 seconds and northeast 1 foot at 10 seconds.

TUESDAY NIGHT
East winds 15 to 20 knots with gusts up to 30 knots. Seas around 6 feet, occasionally to 8 feet. Wave Detail: East 6 feet at 6 seconds and northeast 1 foot at 10 seconds. Scattered showers in the evening.

WEDNESDAY
East winds 15 to 20 knots with gusts up to 25 knots. Seas 5 to 6 feet, occasionally to 8 feet. Wave Detail: East 6 feet at 7 seconds.

WEDNESDAY NIGHT
East winds 15 to 20 knots with gusts up to 25 knots. Seas 5 to 6 feet, occasionally to 8 feet. Wave Detail: East 6 feet at 7 seconds. Scattered showers.

THURSDAY
East winds 15 to 20 knots. Seas around 5 feet, occasionally to 6 feet. Scattered showers in the morning.

THURSDAY NIGHT
East winds 15 to 20 knots. Seas around 5 feet, occasionally to 6 feet.

FRIDAY
East winds 15 to 20 knots, diminishing to 10 to 15 knots in the afternoon. Seas 4 to 5 feet, occasionally to 6 feet. Scattered showers.

FRIDAY NIGHT
East winds around 10 knots. Seas 4 to 5 feet, occasionally to 6 feet. Scattered showers.


AMZ726-122115
Coastal waters east of Puerto Rico, around Vieques, and around and just north of Culebra and Saint John
444 AM AST Mon May 12 2025

SMALL CRAFT SHOULD EXERCISE CAUTION

TODAY
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. Isolated showers.

TONIGHT
East winds 15 to 20 knots with gusts up to 30 knots. Seas 4 to 6 feet, occasionally to 8 feet. Wave Detail: East 5 feet at 7 seconds.

TUESDAY
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.

TUESDAY 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 7 seconds.

WEDNESDAY
East winds 15 to 20 knots with gusts up to 25 knots. Seas 4 to 6 feet, occasionally to 8 feet. Wave Detail: East 5 feet at 6 seconds. Scattered showers in the afternoon.

WEDNESDAY 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 7 seconds. Scattered showers.

THURSDAY
East winds 15 to 20 knots. Seas 3 to 5 feet, occasionally to 6 feet. Scattered showers.

THURSDAY NIGHT
East winds 15 to 20 knots. Seas 3 to 5 feet, occasionally to 6 feet.

FRIDAY
East winds 15 to 20 knots, diminishing to 10 to 15 knots in the afternoon. Seas 3 to 5 feet, occasionally to 6 feet. Scattered showers in the morning, then numerous showers in the afternoon.

FRIDAY NIGHT
East winds 5 to 10 knots. Seas 3 to 4 feet, occasionally to 5 feet. Scattered showers.


AMZ733-122115
Caribbean waters of Puerto Rico from 10 NM to 17N, including the coastal waters of Saint Croix
444 AM AST Mon May 12 2025

SMALL CRAFT SHOULD EXERCISE CAUTION

TODAY
East winds 15 to 20 knots with gusts up to 25 knots. Seas 5 to 6 feet, occasionally to 8 feet. Wave Detail: East 5 feet at 7 seconds. Isolated showers.

TONIGHT
East winds 15 to 20 knots with gusts up to 30 knots. Seas 5 to 6 feet, occasionally to 8 feet. Wave Detail: East 6 feet at 7 seconds.

TUESDAY
East winds 15 to 20 knots with gusts up to 25 knots. Seas 5 to 6 feet, occasionally to 8 feet. Wave Detail: East 6 feet at 7 seconds.

TUESDAY NIGHT
East winds 15 to 20 knots with gusts up to 25 knots. Seas 5 to 6 feet, occasionally to 8 feet. Wave Detail: East 5 feet at 7 seconds. Scattered showers.

WEDNESDAY
East winds 15 to 20 knots with gusts up to 25 knots. Seas 5 to 6 feet, occasionally to 8 feet. Wave Detail: East 5 feet at 7 seconds. Scattered showers.

WEDNESDAY NIGHT
East winds 15 to 20 knots with gusts up to 25 knots. Seas around 5 feet, occasionally to 6 feet. Wave Detail: East 5 feet at 7 seconds. Scattered showers.

THURSDAY
East winds around 15 knots. Seas 4 to 5 feet, occasionally to 6 feet. Scattered showers in the morning.

THURSDAY NIGHT
East winds 15 to 20 knots. Seas 4 to 5 feet, occasionally to 6 feet.

FRIDAY
East winds 15 to 20 knots, diminishing to 10 to 15 knots in the afternoon. Seas 4 to 5 feet, occasionally to 6 feet. Scattered showers.

FRIDAY NIGHT
East winds 10 to 15 knots. Seas around 4 feet, occasionally to 5 feet. Scattered showers.


AMZ735-122115
Coastal Waters of Southern Puerto Rico out 10 NM
444 AM AST Mon May 12 2025

SMALL CRAFT SHOULD EXERCISE CAUTION

TODAY
East winds 10 to 15 knots, increasing to 15 to 20 knots this afternoon. Seas 3 to 5 feet, occasionally to 6 feet. Wave Detail: East 5 feet at 7 seconds. Isolated showers late this morning and afternoon.

TONIGHT
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.

TUESDAY
East winds 10 to 15 knots, increasing to 15 to 20 knots in the afternoon. Seas 3 to 5 feet, occasionally to 6 feet. Wave Detail: East 5 feet at 7 seconds.

TUESDAY NIGHT
East winds 15 to 20 knots, diminishing to 10 to 15 knots after midnight. Seas 3 to 5 feet, occasionally to 6 feet. Wave Detail: East 5 feet at 7 seconds.

WEDNESDAY
East winds 10 to 15 knots with gusts up to 25 knots. Seas 3 to 5 feet, occasionally to 6 feet. Wave Detail: East 4 feet at 7 seconds.

WEDNESDAY NIGHT
East winds 10 to 15 knots with gusts up to 25 knots. Seas 3 to 5 feet, occasionally to 6 feet. Wave Detail: East 4 feet at 7 seconds.

THURSDAY
East winds 10 to 15 knots. Seas 3 to 4 feet, occasionally to 5 feet.

THURSDAY NIGHT
East winds 10 to 15 knots. Seas 3 to 4 feet, occasionally to 5 feet.

FRIDAY
East winds 10 to 15 knots, diminishing to 5 to 10 knots in the afternoon. Seas 3 to 4 feet, occasionally to 5 feet.

FRIDAY NIGHT
East winds 5 to 10 knots. Seas 3 to 4 feet, occasionally to 5 feet. Scattered showers.


AMZ741-122115
Mona Passage Southward to 17N
444 AM AST Mon May 12 2025

SMALL CRAFT SHOULD EXERCISE CAUTION

TODAY
East winds 15 to 20 knots with gusts up to 25 knots. Seas 4 to 6 feet, occasionally to 8 feet. Wave Detail: East 5 feet at 7 seconds. Isolated showers.

TONIGHT
East winds 15 to 20 knots with gusts up to 30 knots. Seas 4 to 6 feet, occasionally to 8 feet. Wave Detail: East 6 feet at 7 seconds.

TUESDAY
East winds 15 to 20 knots with gusts up to 25 knots. Seas 5 to 6 feet, occasionally to 8 feet. Wave Detail: East 6 feet at 7 seconds. Scattered showers in the afternoon.

TUESDAY NIGHT
East winds 15 to 20 knots with gusts up to 25 knots. Seas 5 to 6 feet, occasionally to 8 feet. Wave Detail: East 5 feet at 7 seconds.

WEDNESDAY
East winds 15 to 20 knots, diminishing to 10 to 15 knots in the afternoon. Seas 4 to 5 feet, occasionally to 6 feet. Wave Detail: East 5 feet at 7 seconds.

WEDNESDAY 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 7 seconds.

THURSDAY
East winds 15 to 20 knots. Seas 4 to 5 feet, occasionally to 6 feet. Scattered showers in the afternoon.

THURSDAY NIGHT
East winds 10 to 15 knots. Seas 4 to 5 feet, occasionally to 6 feet.

FRIDAY
East winds 10 to 15 knots, diminishing to 5 to 10 knots in the afternoon. Seas around 4 feet, occasionally to 5 feet.

FRIDAY NIGHT
East winds 10 to 15 knots. Seas 3 to 4 feet, occasionally to 5 feet. Scattered showers.


AMZ742-122115
Coastal Waters of Northwestern Puerto Rico out 10 NM
444 AM AST Mon May 12 2025

TODAY
East winds 5 to 10 knots with gusts up to 20 knots, increasing to 10 to 15 knots with gusts up to 25 knots late. Seas 2 to 4 feet, occasionally to 5 feet. Wave Detail: Northeast 3 feet at 7 seconds. Showers with isolated thunderstorms early this afternoon. Scattered showers with isolated thunderstorms late.

TONIGHT
East winds 10 to 15 knots with gusts up to 25 knots. Seas 2 to 4 feet, occasionally to 5 feet. Wave Detail: Northeast 4 feet at 8 seconds.

TUESDAY
East winds 10 to 15 knots with gusts up to 25 knots. Seas 2 to 4 feet, occasionally to 5 feet. Wave Detail: Northeast 4 feet at 7 seconds. Scattered showers in the afternoon.

TUESDAY NIGHT
East winds 10 to 15 knots, diminishing to 5 to 10 knots after midnight. Seas 2 to 4 feet, occasionally to 5 feet. Wave Detail: Northeast 4 feet at 7 seconds.

WEDNESDAY
East winds 5 to 10 knots. Seas 2 to 4 feet, occasionally to 5 feet. Wave Detail: Northeast 3 feet at 7 seconds. Scattered showers in the afternoon.

WEDNESDAY NIGHT
East winds 10 to 15 knots, diminishing to 5 to 10 knots after midnight. Seas 2 to 4 feet, occasionally to 5 feet. Wave Detail: Northeast 3 feet at 7 seconds.

THURSDAY
East winds 5 to 10 knots. Seas 2 to 4 feet, occasionally to 5 feet. Scattered showers in the afternoon.

THURSDAY NIGHT
East winds 5 to 10 knots. Seas 2 to 3 feet, occasionally to 4 feet.

FRIDAY
East winds around 5 knots, increasing to 5 to 10 knots in the afternoon. Seas 2 to 3 feet, occasionally to 4 feet. Numerous showers in the afternoon.

FRIDAY NIGHT
East winds 5 to 10 knots. Seas 2 to 3 feet, occasionally to 4 feet.

Winds and seas higher in and near thunderstorms.


AMZ745-122115
Coastal Waters of Southwestern Puerto Rico out 10 NM
444 AM AST Mon May 12 2025

TODAY
East winds 5 to 10 knots with gusts up to 20 knots, increasing to 10 to 15 knots with gusts up to 25 knots this afternoon. Seas 2 to 3 feet, occasionally to 4 feet. Wave Detail: Southeast 2 feet at 6 seconds. Numerous showers with isolated thunderstorms early this afternoon. Scattered showers with isolated thunderstorms late.

TONIGHT
East winds 10 to 15 knots with gusts up to 20 knots, diminishing to 5 to 10 knots after midnight. Seas 2 to 3 feet, occasionally to 4 feet. Wave Detail: Southeast 2 feet at 6 seconds.

TUESDAY
East winds 5 to 10 knots, becoming southeast 10 to 15 knots with gusts up to 25 knots in the afternoon. Seas 2 to 3 feet, occasionally to 4 feet. Wave Detail: East 2 feet at 6 seconds. Scattered showers in the afternoon.

TUESDAY NIGHT
East winds 10 to 15 knots with gusts up to 20 knots. Seas 2 to 3 feet, occasionally to 4 feet. Wave Detail: Southeast 2 feet at 6 seconds.

WEDNESDAY
East winds 10 to 15 knots, becoming southeast 15 to 20 knots in the afternoon. Seas 2 to 3 feet, occasionally to 4 feet. Wave Detail: Southeast 3 feet at 6 seconds.

WEDNESDAY NIGHT
East winds 10 to 15 knots with gusts up to 25 knots. Seas 2 to 3 feet, occasionally to 4 feet. Wave Detail: Southeast 3 feet at 5 seconds.

THURSDAY
East winds 10 to 15 knots. Seas 2 to 3 feet, occasionally to 4 feet.

THURSDAY NIGHT
East winds 10 to 15 knots. Seas 2 to 3 feet, occasionally to 4 feet.

FRIDAY
East winds 10 to 15 knots, diminishing to 5 to 10 knots in the afternoon. Seas 2 to 3 feet, occasionally to 4 feet. Scattered showers in the afternoon.

FRIDAY NIGHT
East winds 5 to 10 knots. Seas around 2 feet.

Winds and seas higher in and near thunderstorms.