

550 

FZCA52 TJSJ 200947

CWFSJU



Coastal Waters Forecast

National Weather Service San Juan PR

547 AM AST Thu Aug 20 2020



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 Seas...Along with the occasional height

of the average highest 10 percent of the Seas.



AMZ700-202230-

547 AM AST Thu Aug 20 2020



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

More tranquil seas are expected today as winds diminish. A surface 

trough will cross the regional waters tonight into Friday, with 

shower and isolated thunderstorm activity expected across portions of

the area. This will be followed by Tropical Depression Thirteen, 

which is forecast to become a tropical storm as it crosses the region

late Friday through the upcoming weekend. This system is expected to

bring hazardous marine conditions as well as numerous shower and 

isolated thunderstorm activity.



$$



AMZ710-202230-

Atlantic Waters of Puerto Rico and USVI from 10 NM to 19.5N-

547 AM AST Thu Aug 20 2020



.TODAY...East winds 10 to 15 knots. Seas 3 to 5 feet with

occasional seas up to 6 feet. Dominant period 8 seconds. Scattered

showers through the day. Isolated thunderstorms in the afternoon.

.TONIGHT...East winds 15 to 20 knots. Seas 4 to 6 feet with

occasional seas up to 8 feet. Dominant period 8 seconds. Scattered

showers and isolated thunderstorms.

.FRIDAY...East winds 15 to 20 knots. Seas 4 to 6 feet with

occasional seas up to 8 feet. Dominant period 8 seconds. Isolated

thunderstorms in the morning. Scattered showers through the day.

.FRIDAY NIGHT... Tropical storm conditions possible. Northeast

winds 15 to 20 knots with gusts to around 30 knots rising to 40 to

45 knots with gusts to around 60 knots after midnight. Seas 8 to

10 feet with occasional seas up to 11 feet. Dominant period 10

seconds. North swell 4 to 5 feet. Numerous showers and isolated

thunderstorms.

.SATURDAY... Tropical storm conditions possible. Southeast winds

35 to 45 knots. Gusts up to 60 knots subsiding to 50 knots in the

afternoon. Seas 8 to 10 feet with occasional seas up to 13 feet.

Dominant period 10 seconds. Northeast swell 4 to 5 feet. Numerous

showers and isolated thunderstorms.

.SATURDAY NIGHT...Southeast winds 20 to 25 knots. Seas 8 to 10

feet with occasional seas up to 13 feet. Dominant period 10

seconds. Northeast swell 4 to 5 feet. Numerous showers and

isolated thunderstorms.

.SUNDAY...East winds 15 to 20 knots. Seas 8 to 10 feet with

occasional seas up to 11 feet. Dominant period 10 seconds.

Northeast swell around 4 feet. Scattered showers and isolated

thunderstorms.

.SUNDAY NIGHT...East winds 10 to 15 knots with gusts to around 25

knots. Seas 5 to 7 feet with occasional seas up to 9 feet.

Dominant period 10 seconds. Isolated showers.

.MONDAY...East winds 10 to 15 knots. Seas 3 to 5 feet with

occasional seas up to 6 feet. Dominant period 8 seconds. Isolated

showers.



$$



AMZ712-202230-

Coastal Waters of Northern Puerto Rico out 10 NM-

547 AM AST Thu Aug 20 2020



...SMALL CRAFT SHOULD EXERCISE CAUTION...



.TODAY...East winds 15 to 20 knots. Seas 3 to 5 feet with

occasional seas up to 6 feet. Dominant period 7 seconds. Isolated

showers through the day.

.TONIGHT...East winds 15 to 20 knots. Seas 3 to 5 feet with

occasional seas up to 6 feet. Dominant period 7 seconds. Numerous

showers and isolated thunderstorms.

.FRIDAY...East winds 10 to 15 knots. Seas 2 to 4 feet with

occasional seas up to 5 feet. Dominant period 7 seconds. Scattered

showers and isolated thunderstorms.

.FRIDAY NIGHT...Northeast winds 10 to 15 knots. Seas 3 to 5 feet

with occasional seas up to 6 feet. Dominant period 7 seconds.

Numerous showers and isolated thunderstorms.

.SATURDAY...East winds 10 to 15 knots veering southeast in the

afternoon. Seas 4 to 6 feet with occasional seas up to 8 feet.

Dominant period 8 seconds. Numerous showers and isolated

thunderstorms.

.SATURDAY NIGHT...Southeast winds 15 to 20 knots. Seas 5 to 7 feet

with occasional seas up to 9 feet. Dominant period 10 seconds.

Northeast swell around 4 feet after midnight. Numerous showers and

isolated thunderstorms.

.SUNDAY...East winds 10 to 15 knots. Seas 5 to 7 feet with

occasional seas up to 9 feet. Dominant period 10 seconds.

Northeast swell around 4 Feet. Scattered showers and isolated

thunderstorms.

.SUNDAY NIGHT...East winds 10 to 15 knots. Seas 4 to 6 feet with

occasional seas up to 8 feet. Dominant period 10 seconds. Isolated

showers.

.MONDAY...East winds 10 to 15 knots. Seas 3 to 5 feet with

occasional seas up to 6 feet. Dominant period 8 seconds. Scattered

showers.



$$



AMZ715-202230-

Coastal Waters of Northern USVI and Culebra out 10 NM-

547 AM AST Thu Aug 20 2020



.TODAY...East winds 10 to 15 knots. Seas 2 to 4 feet with

occasional seas up to 5 feet. Dominant period 8 seconds. Scattered

showers through the day. Isolated thunderstorms in the afternoon.

.TONIGHT...East winds 15 to 20 knots. Seas 2 to 4 feet with

occasional seas up to 5 feet. Dominant period 8 seconds. Scattered

showers and isolated thunderstorms.

.FRIDAY...East winds 15 to 20 knots. Seas 2 to 4 feet with

occasional seas up to 5 feet. Dominant period 8 seconds. Scattered

showers and isolated thunderstorms.

.FRIDAY NIGHT... Tropical storm conditions possible. Northeast

winds 15 to 20 knots. Seas 3 to 5 feet with occasional seas up to

6 feet. Dominant period 10 seconds. Numerous showers and isolated

thunderstorms.

.SATURDAY...Southeast winds 20 to 25 knots. Seas 5 to 7 feet with

occasional seas up to 9 feet. Dominant period 10 seconds. Numerous

showers and isolated thunderstorms.

.SATURDAY NIGHT...Southeast winds 20 to 25 knots with gusts to

around 35 knots. Seas 5 to 7 feet with occasional seas up to 9

feet. Dominant period 10 seconds. Numerous showers and isolated

thunderstorms.

.SUNDAY...East winds 15 to 20 knots. Seas 4 to 6 feet with

occasional seas up to 8 feet. Dominant period 8 seconds. Isolated

showers.

.SUNDAY NIGHT...East winds 10 to 15 knots with gusts to around 25

knots. Seas 2 to 4 feet with occasional seas up to 5 feet.

Dominant period 7 seconds. Isolated showers.

.MONDAY...East winds 10 to 15 knots. Seas 2 to 4 feet with

occasional seas up to 5 feet. Dominant period 7 seconds. Scattered

showers.



$$



AMZ722-202230-

Anegada Passage Southward to 17N-

547 AM AST Thu Aug 20 2020



.TODAY...East winds 10 to 15 knots with gusts to around 25 knots.

Seas 3 to 5 feet with occasional seas up to 6 feet. Dominant

period 8 seconds. Numerous showers through the day. Isolated

thunderstorms in the afternoon.

.TONIGHT...East winds 15 to 20 knots. Seas 3 to 5 feet with

occasional seas up to 6 feet. Dominant period 8 seconds. Scattered

showers and isolated thunderstorms.

.FRIDAY...East winds 15 to 20 knots. Seas 4 to 6 feet with

occasional seas up to 8 feet. Dominant period 8 seconds. Scattered

showers through the day. Isolated thunderstorms in the afternoon.

.FRIDAY NIGHT...Tropical storm conditions possible. East winds 15 to

20 knots. Seas 6 to 8 feet with occasional seas up to 10 feet. 

Dominant period 10 seconds. East swell around 4 feet. Numerous 

showers and isolated thunderstorms.

.SATURDAY...Southeast winds 15 to 20 knots with gusts to around 30

knots. Seas 8 to 10 feet with occasional seas up to 11 feet.

Dominant period 10 seconds. Northeast swell 4 to 5 feet. Numerous

showers and isolated thunderstorms.

.SATURDAY NIGHT...Southeast winds 20 to 25 knots. Seas 6 to 8 feet

with occasional seas up to 10 feet. Dominant period 8 seconds.

Northeast swell around 4 feet. Numerous showers and isolated

thunderstorms.

.SUNDAY...East winds 15 to 20 knots. Seas 4 to 6 feet with

occasional seas up to 8 feet. Dominant period 7 seconds. Isolated

showers.

.SUNDAY NIGHT...East winds 15 to 20 knots. Seas 3 to 5 feet with

occasional seas up to 6 feet. Dominant period 7 seconds. Isolated

showers.

.MONDAY...Northeast winds 15 to 20 knots. Seas 3 to 5 feet with

occasional seas up to 6 feet. Dominant period 7 seconds. Scattered

showers.



$$



AMZ725-202230-

Coastal Waters of Southern USVI Vieques and Eastern Puerto Rico out

10 NM-

547 AM AST Thu Aug 20 2020



.TODAY...East winds 10 to 15 knots. Seas 2 to 4 feet with

occasional seas up to 5 feet. Dominant period 8 seconds. Scattered

showers through the day. Isolated thunderstorms in the afternoon.

.TONIGHT...East winds 15 to 20 knots. Seas 3 to 5 feet with

occasional seas up to 6 feet. Dominant period 7 seconds. Numerous

showers and isolated thunderstorms.

.FRIDAY...East winds 10 to 15 knots. Gusts up to 25 knots in the

morning. Seas 3 to 5 feet with occasional seas up to 6 feet.

Dominant period 8 seconds. Scattered showers and isolated

thunderstorms.

.FRIDAY NIGHT... Tropical storm conditions possible. Northeast

winds 15 to 20 knots. Seas 4 to 6 feet with occasional seas up to

8 feet. Dominant period 10 seconds. Numerous showers and isolated

thunderstorms.

.SATURDAY...Southeast winds 15 to 20 knots with gusts to around 30

knots. Seas 6 to 8 feet with occasional seas up to 10 feet.

Dominant period 10 seconds. East swell around 4 feet. Numerous

showers and isolated thunderstorms.

.SATURDAY NIGHT...Southeast winds 20 to 25 knots with gusts to

around 35 knots. Seas 6 to 8 feet with occasional seas up to 10

feet. Dominant period 10 seconds. Northeast swell around 4 feet.

Numerous showers and isolated thunderstorms.

.SUNDAY...East winds 15 to 20 knots. Seas 4 to 6 feet with

occasional seas up to 8 feet. Dominant period 8 seconds. Isolated

thunderstorms in the morning. Scattered showers through the day.

.SUNDAY NIGHT...East winds 10 to 15 knots. Gusts up to 25 knots

after midnight. Seas 3 to 5 feet with occasional seas up to 6

feet. Dominant period 7 seconds. Isolated showers.

.MONDAY...East winds 10 to 15 knots. Seas 3 to 5 feet with

occasional seas up to 6 feet. Dominant period 7 seconds. Scattered

showers.



$$



AMZ732-202230-

Caribbean Waters of Puerto Rico from 10 NM to 17N-

547 AM AST Thu Aug 20 2020



...SMALL CRAFT SHOULD EXERCISE CAUTION...



.TODAY...East winds 15 to 20 knots. Seas 3 to 5 feet with

occasional seas up to 6 feet. Dominant period 7 seconds. Numerous

showers through the day. Isolated thunderstorms in the afternoon.

.TONIGHT...East winds 15 to 20 knots. Seas 3 to 5 feet with

occasional seas up to 6 feet. Dominant period 7 seconds. Numerous

showers and isolated thunderstorms.

.FRIDAY...East winds 10 to 15 knots. Gusts up to 25 knots in the

morning. Seas 3 to 5 feet with occasional seas up to 6 feet.

Dominant period 8 seconds. Scattered showers through the day.

Isolated thunderstorms in the afternoon.

.FRIDAY NIGHT... Tropical storm conditions possible. Northeast

winds 10 to 15 knots. Gusts up to 25 knots in the evening. Seas 2

to 4 feet with occasional seas up to 5 feet. Dominant period 8

seconds. Numerous showers and isolated thunderstorms.

.SATURDAY...Southeast winds 15 to 20 knots. Seas 5 to 7 feet with

occasional seas up to 9 feet. Dominant period 10 seconds. Numerous

showers and isolated thunderstorms.

.SATURDAY NIGHT...Southeast winds 15 to 20 knots with gusts to

around 30 knots. Seas 5 to 7 feet with occasional seas up to 9

feet. Dominant period 10 seconds. Numerous showers and isolated

thunderstorms.

.SUNDAY...East winds 15 to 20 knots. Seas 5 to 7 feet with

occasional seas up to 9 feet. Dominant period 7 seconds. Scattered

showers and isolated thunderstorms.

.SUNDAY NIGHT...East winds 15 to 20 knots. Seas 4 to 6 feet with

occasional seas up to 8 feet. Dominant period 7 seconds. Isolated

showers.

.MONDAY...East winds 15 to 20 knots. Seas 3 to 5 feet with

occasional seas up to 6 feet. Dominant period 7 seconds. Isolated

showers.



$$



AMZ735-202230-

Coastal Waters of Southern Puerto Rico out 10 NM-

547 AM AST Thu Aug 20 2020



.TODAY...East winds 10 to 15 knots with gusts to around 25 knots.

Seas 3 to 5 feet with occasional seas up to 6 feet. Dominant

period 7 seconds. Isolated showers through the day.

.TONIGHT...Northeast winds 10 to 15 knots. Gusts up to 25 knots in

the evening. Seas 2 to 4 feet with occasional seas up to 5 feet.

Dominant period 7 seconds. Scattered showers and isolated

thunderstorms.

.FRIDAY...East winds 10 to 15 knots. Seas 2 to 4 feet with

occasional seas up to 5 feet. Dominant period 7 seconds. Isolated

showers in the morning, then isolated thunderstorms in the

afternoon.

.FRIDAY NIGHT...Northeast winds 10 to 15 knots. Seas 2 to 4 feet

with occasional seas up to 5 feet. Dominant period 7 seconds.

Scattered showers and isolated thunderstorms.

.SATURDAY...Northeast winds 5 to 10 knots veering southeast in the

afternoon. Seas 1 to 3 feet. Dominant period 8 seconds. Numerous

showers and isolated thunderstorms.

.SATURDAY NIGHT...Southeast winds 15 to 20 knots with gusts to

around 30 knots. Seas 4 to 6 feet with occasional seas up to 8

feet. Dominant period 8 seconds. Numerous showers and isolated

thunderstorms.

.SUNDAY...East winds 15 to 20 knots. Seas 4 to 6 feet with

occasional seas up to 8 feet. Dominant period 7 seconds. Scattered

showers and isolated thunderstorms.

.SUNDAY NIGHT...Northeast winds 10 to 15 knots. Seas 3 to 5 feet

with occasional seas up to 6 feet. Dominant period 7 seconds.

Isolated showers.

.MONDAY...East winds 10 to 15 knots. Seas 3 to 5 feet with

occasional seas up to 6 feet. Dominant period 7 seconds. Isolated

showers.



$$



AMZ741-202230-

Mona Passage Southward to 17N-

547 AM AST Thu Aug 20 2020



...SMALL CRAFT SHOULD EXERCISE CAUTION...



.TODAY...East winds 15 to 20 knots. Seas 4 to 6 feet with

occasional seas up to 8 feet. Dominant period 7 seconds. Isolated

showers through the day.

.TONIGHT...Northeast winds 15 to 20 knots. Seas 3 to 5 feet with

occasional seas up to 6 feet. Dominant period 7 seconds. Scattered

showers through the night. Isolated thunderstorms after midnight.

.FRIDAY...Northeast winds 10 to 15 knots. Seas 3 to 5 feet with

occasional seas up to 6 feet. Dominant period 7 seconds. Scattered

showers through the day. Isolated thunderstorms in the afternoon.

.FRIDAY NIGHT...Northeast winds 15 to 20 knots. Seas 2 to 4 feet

with occasional seas up to 5 feet. Dominant period 7 seconds.

Isolated thunderstorms in the evening. Scattered showers through

the night.

.SATURDAY...Northeast winds 10 to 15 knots with gusts to around 25

knots veering southeast in the afternoon. Seas 2 to 4 feet with

occasional seas up to 5 feet. Dominant period 8 seconds. Numerous

showers through the day. Isolated thunderstorms in the afternoon.

.SATURDAY NIGHT...Southeast winds 20 to 25 knots. Seas 4 to 6 feet

with occasional seas up to 8 feet. Dominant period 8 seconds.

Scattered showers and isolated thunderstorms.

.SUNDAY...Southeast winds 20 to 25 knots. Seas 5 to 7 feet with

occasional seas up to 9 feet. Dominant period 10 seconds. Numerous

showers and isolated thunderstorms.

.SUNDAY NIGHT...East winds 15 to 20 knots. Seas 4 to 6 feet with

occasional seas up to 8 feet. Dominant period 10 seconds.

Scattered showers.

.MONDAY...East winds 15 to 20 knots. Seas 4 to 6 feet with

occasional seas up to 8 feet. Dominant period 7 seconds. Isolated

showers.



$$



AMZ742-202230-

Coastal Waters of Northwestern Puerto Rico out 10 NM-

547 AM AST Thu Aug 20 2020



.TODAY...East winds 10 to 15 knots. Seas 2 to 4 feet with

occasional seas up to 5 feet. Dominant period 8 seconds. Scattered

showers through the day. Isolated thunderstorms in the afternoon.

.TONIGHT...Northeast winds 10 to 15 knots with gusts to around 25

knots. Seas 2 to 4 feet with occasional seas up to 5 feet.

Dominant period 8 seconds. Isolated thunderstorms in the evening.

Scattered showers through the night.

.FRIDAY...Northeast winds 10 to 15 knots. Seas 2 to 4 feet with

occasional seas up to 5 feet. Dominant period 8 seconds. Numerous

showers and isolated thunderstorms.

.FRIDAY NIGHT...Northeast winds 10 to 15 knots. Gusts up to 25

knots in the evening. Seas 2 to 4 feet with occasional seas up to

5 feet. Dominant period 7 seconds. Scattered showers through the

night. Isolated thunderstorms after midnight.

.SATURDAY...Northeast winds 10 to 15 knots veering southeast in

the afternoon. Seas 2 to 4 feet with occasional seas up to 5 feet.

Dominant period 7 seconds. Numerous showers and isolated

thunderstorms.

.SATURDAY NIGHT...Southeast winds 15 to 20 knots. Seas 3 to 5 feet

with occasional seas up to 6 feet. Dominant period 8 seconds.

Numerous showers and isolated thunderstorms.

.SUNDAY...Southeast winds 15 to 20 knots. Seas 3 to 5 feet with

occasional seas up to 6 feet. Dominant period 10 seconds. Numerous

showers and isolated thunderstorms.

.SUNDAY NIGHT...East winds 10 to 15 knots. Seas 3 to 5 feet with

occasional seas up to 6 feet. Dominant period 8 seconds. Isolated

showers.

.MONDAY...East winds 10 to 15 knots. Seas 2 to 4 feet with

occasional seas up to 5 feet. Dominant period 7 seconds. Isolated

showers.



$$



AMZ745-202230-

Coastal Waters of Southwestern Puerto Rico out 10 NM-

547 AM AST Thu Aug 20 2020



.TODAY...East winds 10 to 15 knots. Seas 1 to 3 feet. Dominant

period 7 seconds.

.TONIGHT...Northeast winds 10 to 15 knots. Seas 1 to 3 feet.

Dominant period 7 seconds. Scattered showers.

.FRIDAY...East winds 5 to 10 knots. Seas 1 to 3 feet. Dominant

period 7 seconds. Scattered showers through the day. Isolated

thunderstorms in the afternoon.

.FRIDAY NIGHT...Northeast winds 10 to 15 knots. Seas 2 feet or

less. Dominant period 7 seconds. Isolated showers.

.SATURDAY...Northeast winds 10 to 15 knots veering southeast in

the afternoon. Seas 2 feet or less. Dominant period 7 seconds.

Numerous showers through the day. Isolated thunderstorms in the

afternoon.

.SATURDAY NIGHT...Southeast winds 15 to 20 knots with gusts to

around 30 knots. Seas 2 to 4 feet with occasional seas up to 5

feet. Dominant period 7 seconds. Numerous showers and isolated

thunderstorms.

.SUNDAY...Southeast winds 15 to 20 knots. Seas 2 to 4 feet with

occasional seas up to 5 feet. Dominant period 7 seconds. Numerous

showers and isolated thunderstorms.

.SUNDAY NIGHT...East winds 10 to 15 knots. Seas 2 to 4 feet with

occasional seas up to 5 feet. Dominant period 7 seconds. Isolated

showers.

.MONDAY...East winds 5 to 10 knots. Seas 1 to 3 feet. Dominant

period 7 seconds. Scattered showers through the day. Isolated

thunderstorms in the afternoon.



$$

