476
FZNT31 KNHC 210904
OFFN20
MARINE WEATHER HF VOICE BROADCAST
NWS NATIONAL HURRICANE CENTER MIAMI, FL
504 AM EDT THU AUG 21 2025
MARINE WEATHER HF VOICE BROADCAST FOR THE TROPICAL N ATLANTIC
FROM 07N TO 19N W OF 55W, THE N ATLANTIC FROM 19N TO
31N W OF 55W INCLUDING THE BAHAMAS, AND THE CARIBBEAN SEA.
SEAS GIVEN AS SIGNIFICANT WAVE HEIGHT, WHICH IS THE AVERAGE
HEIGHT OF THE HIGHEST 1/3 OF THE WAVES. INDIVIDUAL WAVES MAY BE
MORE THAN TWICE THE SIGNIFICANT WAVE HEIGHT.
SYNOPSIS FOR CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM
07N TO 19N W OF 55W
SYNOPSIS
FRESH TO LOCALLY STRONG TRADES AND MODERATE SEAS
SEAS WILL EXIST OVER THE CENTRAL AND EASTERN CARIBBEAN THROUGH
FRI AS A STRENGTHENING PRESSURE GRADIENT DEVELOPS BETWEEN LOW
PRESSURE OVER COLOMBIA AND BUILDING HIGH PRESSURE IN THE WAKE OF
HURRICANE ERIN IN THE WESTERN ATLANTIC. ELSEWHERE, FRESH TO
OCCASIONALLY STRONG EAST TO SOUTHEAST WINDS WILL PULSE IN THE
GULF OF HONDURAS BEGINNING TONIGHT. LONG PERIOD NORTHWEST TO
NORTH SWELL FROM HURRICANE ERIN WILL BEGIN TO IMPACT THE
TROPICAL N ATLANTIC ZONES FROM LATE ON FRI THROUGH MON. LOOKING
AHEAD, SHOWER AND THUNDERSTORM ACTIVITY HAS BECOME A BIT MORE
CONCENTRATED IN ASSOCIATION WITH A TROPICAL WAVE LOCATED A FEW
HUNDRED MILES EAST OF THE LEEWARD ISLANDS. ENVIRONMENTAL
CONDITIONS APPEAR CONDUCIVE FOR FURTHER DEVELOPMENT OF THIS
SYSTEM, AND A TROPICAL DEPRESSION IS LIKELY TO FORM THIS WEEKEND
WHILE IT MOVES NEAR OR TO THE NORTH OF THE NORTHERN LEEWARD
ISLANDS.
NW CARIBBEAN W OF 85W
TODAY
SE WINDS 10 TO 15 KT. SEAS 2 FT OR LESS.
TONIGHT
E WINDS 10 TO 20 KT. SEAS 3 TO 5 FT.
FRI
SE WINDS 10 TO 20 KT. SEAS 3 TO 5 FT.
FRI NIGHT
SE WINDS 15 TO 25 KT. SEAS 3 TO 5 FT.
SAT
E WINDS 15 TO 25 KT. SEAS 3 TO 5 FT.
SAT NIGHT
E WINDS 15 TO 25 KT. SEAS 3 TO 5 FT.
SUN
E WINDS 10 TO 20 KT. SEAS 3 TO 5 FT.
SUN NIGHT
E WINDS 10 TO 20 KT. SEAS 3 TO 4 FT.
MON
E WINDS 15 TO 25 KT. SEAS 3 TO 5 FT.
CARIBBEAN N OF 15N BETWEEN 72W AND 85W
TODAY
E WINDS 10 TO 20 KT. SEAS 3 TO 5 FT S OF 18N, AND 2 FT
OR LESS ELSEWHERE.
TONIGHT
E WINDS 10 TO 20 KT. S OF 18N, SEAS 3 TO 5 FT.
ELSEWHERE, SEAS 2 TO 3 FT.
FRI
E WINDS 10 TO 20 KT. SEAS 4 TO 6 FT S OF 18N, AND 2 TO 4
FT ELSEWHERE.
FRI NIGHT
E WINDS 10 TO 20 KT S OF 18N, AND E 15 TO 25 KT
ELSEWHERE. S OF 18N, SEAS 3 TO 5 FT. ELSEWHERE, SEAS 2 TO 3 FT.
SAT
E WINDS 10 TO 20 KT. SEAS 3 TO 5 FT.
SAT NIGHT
E WINDS 10 TO 20 KT. S OF 18N, SEAS 3 TO 5 FT.
ELSEWHERE, SEAS 2 TO 3 FT.
SUN
E WINDS 10 TO 20 KT. SEAS 3 TO 5 FT S OF 18N, AND 2 TO 3
FT N OF 18N.
SUN NIGHT
E WINDS 10 TO 20 KT. SEAS 3 TO 5 FT.
MON
E WINDS 15 TO 25 KT S OF 18N, AND E 10 TO 20 KT
ELSEWHERE. SEAS 4 TO 6 FT S OF 18N, AND 3 TO 4 FT N OF 18N.
CARIBBEAN FROM 11N TO 15N W OF 72W
TODAY
E WINDS 15 TO 25 KT. SEAS 4 TO 6 FT.
TONIGHT
E WINDS 15 TO 25 KT WITHIN 90 NM OF COAST OF
COLOMBIA, AND E 20 TO 30 KT ELSEWHERE. SEAS 4 TO 6 FT.
FRI
E WINDS 15 TO 25 KT. SEAS 5 TO 7 FT.
FRI NIGHT
E WINDS 15 TO 25 KT. SEAS 4 TO 6 FT.
SAT
E WINDS 10 TO 20 KT WITHIN 90 NM OF COAST OF COLOMBIA,
AND E 15 TO 25 KT ELSEWHERE. SEAS 4 TO 6 FT.
SAT NIGHT
E WINDS 15 TO 25 KT. SEAS 4 TO 5 FT.
SUN
E WINDS 15 TO 25 KT. SEAS 4 TO 6 FT.
SUN NIGHT
E WINDS 15 TO 25 KT. SEAS 5 TO 7 FT.
MON
E WINDS 15 TO 25 KT. SEAS 5 TO 7 FT.
SW CARIBBEAN S OF 11N
TODAY
NE WINDS 10 TO 20 KT. SEAS 3 TO 5 FT.
TONIGHT
NW WINDS 10 TO 15 KT. SEAS 3 TO 5 FT.
FRI
NW WINDS 10 TO 20 KT, SHIFTING TO SW IN THE AFTERNOON.
SEAS 4 TO 6 FT.
FRI NIGHT
W WINDS 10 TO 20 KT. SEAS 4 TO 6 FT.
SAT
W WINDS 10 TO 15 KT, SHIFTING TO SE IN THE AFTERNOON.
SEAS 3 TO 5 FT.
SAT NIGHT
S WINDS 10 TO 15 KT. SEAS 3 TO 5 FT.
SUN
SW WINDS 10 TO 15 KT. SEAS 3 TO 5 FT.
SUN NIGHT
N WINDS 10 TO 15 KT. SEAS 3 TO 4 FT.
MON
W WINDS 10 TO 15 KT. SEAS 3 TO 5 FT.
CARIBBEAN BETWEEN 64W AND 72W
TODAY
E WINDS 15 TO 25 KT. SEAS 4 TO 6 FT.
TONIGHT
E WINDS 15 TO 25 KT. SEAS 4 TO 6 FT.
FRI
E WINDS 15 TO 25 KT GULF OF VENEZUELA, AND E 10 TO 20 KT
ELSEWHERE. SEAS 3 TO 4 FT GULF OF VENEZUELA, AND 4 TO 6 FT
ELSEWHERE.
FRI NIGHT
NE WINDS 15 TO 25 KT GULF OF VENEZUELA, AND E 10 TO
20 KT ELSEWHERE. SEAS 3 TO 5 FT.
SAT
NE WINDS 15 TO 25 KT GULF OF VENEZUELA, AND E 10 TO 20 KT
ELSEWHERE. SEAS 3 TO 5 FT.
SAT NIGHT
E WINDS 15 TO 25 KT. SEAS 4 TO 6 FT.
SUN
E WINDS 15 TO 25 KT. SEAS 4 TO 6 FT.
SUN NIGHT
E WINDS 20 TO 30 KT GULF OF VENEZUELA, AND E 15 TO
25 KT ELSEWHERE. SEAS 4 TO 6 FT.
MON
E WINDS 15 TO 25 KT. SEAS 4 TO 6 FT.
OFFSHORE LEEWARD ISLANDS AND ADJACENT ATLC WATERS FROM 15N TO
19N W OF 55W
TODAY
E WINDS 10 TO 20 KT. SEAS 5 TO 7 FT.
TONIGHT
E WINDS 10 TO 20 KT. SEAS 4 TO 6 FT.
FRI
SE WINDS 15 TO 25 KT. SEAS 4 TO 6 FT.
FRI NIGHT
SE WINDS 10 TO 15 KT. SEAS 3 TO 5 FT.
SAT
E WINDS 10 TO 20 KT. SEAS 4 TO 6 FT.
SAT NIGHT
E WINDS 10 TO 20 KT. SEAS 4 TO 6 FT.
SUN
E WINDS 10 TO 20 KT. SEAS 5 TO 7 FT.
SUN NIGHT
E WINDS 10 TO 20 KT. SEAS 6 TO 8 FT.
MON
E WINDS 10 TO 20 KT. SEAS 6 TO 8 FT.
OFFSHORE WINDWARD ISLANDS AND ADJACENT ATLC WATERS FROM 07N TO
15N W OF 55W
TODAY
SE WINDS 10 TO 15 KT. SEAS 4 TO 6 FT.
TONIGHT
SE WINDS 10 TO 20 KT. SEAS 3 TO 5 FT.
FRI
SE WINDS 10 TO 20 KT. SEAS 3 TO 5 FT.
FRI NIGHT
E WINDS 10 TO 20 KT. SEAS 4 TO 6 FT.
SAT
E WINDS 10 TO 20 KT. SEAS 4 TO 6 FT.
SAT NIGHT
E WINDS 10 TO 20 KT. SEAS 4 TO 6 FT.
SUN
E WINDS 10 TO 20 KT. SEAS 5 TO 7 FT.
SUN NIGHT
E WINDS 10 TO 20 KT. SEAS 5 TO 7 FT.
MON
E WINDS 10 TO 20 KT. SEAS 5 TO 7 FT.
SYNOPSIS FOR THE THE SW N ATLANTIC INCLUDING THE BAHAMAS
SYNOPSIS
HURRICANE ERIN IS LOCATED CENTERED NORTH OF THE AREA
NEAR 34.2N 72.1W AT 5 AM EDT, AND IS MOVING NORTH-NORTHEAST AT
15 KT. MAXIMUM SUSTAINED WINDS ARE 90 KT WITH GUSTS TO 110 KT,
AND THE MINIMUM CENTRAL PRESSURE IS 945 MB. ERIN WILL WILL
CONTINUE TO PULL NNE FAR AWAY FROM THE REGION THROUGH THE END OF
THE WEEK WHILE SLOWLY WEAKENING. LONG PERIOD NORTHERLY SWELLS
GENERATED BY ERIN WILL AFFECT JUST ABOUT THE ENTIRE FORECAST
AREA THROUGH THE NEXT FEW DAYS. IN THE WAKE OF ERIN, CENTRAL
ATLANTIC HIGH PRESSURE WILL BUILD WSW TOWARD THE CENTRAL BAHAMAS
AND THE STRAITS OF FLORIDA THROUGH THE PERIOD. LOOKING AHEAD, A
TROPICAL WAVE LOCATED SEVERAL HUNDRED MILES EAST OF THE LEEWARD
ISLANDS IS PRODUCING A BROAD AREA OF DISORGANIZED SHOWERS AND
THUNDERSTORMS. ENVIRONMENTAL CONDITIONS APPEAR CONDUCIVE FOR
GRADUAL DEVELOPMENT OF THIS SYSTEM, AND A TROPICAL DEPRESSION IS
LIKELY TO FORM BY THIS WEEKEND WHILE IT MOVES NEAR OR TO THE
NORTH OF THE NORTHERN LEEWARD ISLANDS.
ATLC WATERS FROM 27N TO 31N W OF 77W
TODAY
W WINDS 10 TO 20 KT. SEAS 9 TO 14 FT.
TONIGHT
SW WINDS LESS THAN 10 KT. SEAS 7 TO 10 FT.
FRI
W WINDS LESS THAN 10 KT, INCREASING TO 10 TO 15 KT IN THE
AFTERNOON. SEAS 6 TO 9 FT.
FRI NIGHT
S WINDS LESS THAN 10 KT. SEAS 6 TO 9 FT.
SAT
SW WINDS LESS THAN 10 KT. SEAS 6 TO 8 FT.
SAT NIGHT
SW WINDS LESS THAN 10 KT. SEAS 5 TO 7 FT.
SUN
W WINDS 10 TO 15 KT. SEAS 5 TO 7 FT.
SUN NIGHT
W WINDS 10 TO 15 KT. SEAS 5 TO 7 FT.
MON
W WINDS 10 TO 15 KT. SEAS 5 TO 7 FT.
ATLC WATERS FROM 27N TO 31N BETWEEN 65W AND 77W
..TROPICAL STORM WARNING
TODAY
TROPICAL STORM CONDITIONS POSSIBLE. W OF 70W, SW WINDS
30 TO 40 KT, BECOMING W 20 TO 30 KT IN THE AFTERNOON. ELSEWHERE,
S WINDS 25 TO 35 KT. SEAS 12 TO 17 FT.
TONIGHT
W OF 70W, W WINDS 20 TO 30 KT, DIMINISHING TO 10 TO
20 KT LATE. ELSEWHERE, SW WINDS 20 TO 30 KT. SEAS 10 TO 15 FT.
FRI
W WINDS 10 TO 20 KT W OF 70W, AND SW 15 TO 25 KT
ELSEWHERE. SEAS 8 TO 13 FT.
FRI NIGHT
W OF 70W, NW WINDS 10 TO 15 KT, DIMINISHING TO LESS
THAN 10 KT AFTER MIDNIGHT. ELSEWHERE, W WINDS 10 TO 20 KT. SEAS
8 TO 12 FT.
SAT
NW WINDS LESS THAN 10 KT, SHIFTING TO SW IN THE AFTERNOON.
SEAS 8 TO 12 FT.
SAT NIGHT
S WINDS LESS THAN 10 KT. SEAS 8 TO 11 FT.
SUN
W OF 70W, SW WINDS 10 TO 15 KT. ELSEWHERE, VARIABLE WINDS
LESS THAN 10 KT, BECOMING S LESS THAN 10 KT IN THE AFTERNOON.
SEAS 7 TO 10 FT.
SUN NIGHT
SW WINDS 10 TO 15 KT. SEAS 7 TO 8 FT.
MON
SW WINDS 10 TO 20 KT. SEAS 6 TO 8 FT.
BAHAMAS N OF 22N
TODAY
SW WINDS 10 TO 15 KT. SEAS 4 TO 6 FT.
TONIGHT
W WINDS 10 TO 15 KT, SHIFTING TO S LATE.
SEAS 3 TO 5 FT.
FRI
S TO SW WINDS 10 TO 15 KT. SEAS 3 TO 4 FT.
FRI NIGHT
N WINDS LESS THAN 10 KT, SHIFTING TO SE AFTER
MIDNIGHT. SEAS 3 TO 5 FT.
SAT
S WINDS LESS THAN 10 KT. SEAS 3 TO 5 FT.
SAT NIGHT
SE WINDS LESS THAN 10 KT. SEAS 3 TO 5 FT.
SUN
S WINDS LESS THAN 10 KT. SEAS 3 TO 5 FT.
SUN NIGHT
SE WINDS 10 TO 15 KT. SEAS 3 TO 5 FT.
MON
SE WINDS 10 TO 15 KT. SEAS 3 TO 5 FT.
ATLC WATERS FROM 22N TO 27N BETWEEN 65W AND THE BAHAMAS
TODAY
S WINDS 10 TO 20 KT. SEAS 7 TO 10 FT.
TONIGHT
S WINDS 10 TO 20 KT. SEAS 6 TO 9 FT.
FRI
S WINDS 10 TO 15 KT. SEAS 6 TO 8 FT.
FRI NIGHT
W OF 70W, W WINDS LESS THAN 10 KT. ELSEWHERE, NW
WINDS 10 TO 15 KT, SHIFTING TO N AFTER MIDNIGHT. SEAS 6 TO 8 FT.
SAT
SW WINDS LESS THAN 10 KT. SEAS 6 TO 9 FT.
SAT NIGHT
NW WINDS LESS THAN 10 KT, SHIFTING TO S AFTER
MIDNIGHT. SEAS 7 TO 9 FT.
SUN
S WINDS 10 TO 15 KT. SEAS 7 TO 9 FT.
SUN NIGHT
S WINDS 10 TO 15 KT. SEAS 7 TO 8 FT.
MON
S WINDS 10 TO 15 KT. SEAS 6 TO 7 FT.
ATLC WATERS S OF 22N W OF 65W
TODAY
SE WINDS 10 TO 20 KT. SEAS 3 TO 5 FT.
TONIGHT
E WINDS 10 TO 20 KT. SEAS 3 TO 5 FT.
FRI
E WINDS 10 TO 20 KT. SEAS 3 TO 5 FT.
FRI NIGHT
E WINDS 10 TO 20 KT. SEAS 3 TO 5 FT.
SAT
E WINDS 10 TO 15 KT. SEAS 4 TO 6 FT.
SAT NIGHT
E WINDS 10 TO 15 KT. SEAS 4 TO 6 FT.
SUN
E WINDS 10 TO 15 KT. SEAS 4 TO 6 FT.
SUN NIGHT
E WINDS 10 TO 15 KT. SEAS 4 TO 6 FT.
MON
E WINDS 10 TO 20 KT. SEAS 5 TO 7 FT.
ATLC WATERS FROM 19N TO 22N BETWEEN 55W AND 65W
TODAY
E WINDS 10 TO 20 KT. SEAS 5 TO 7 FT.
TONIGHT
E WINDS 10 TO 20 KT. SEAS 6 TO 7 FT.
FRI
E WINDS 10 TO 20 KT, BECOMING SE 20 TO 30 KT IN THE
AFTERNOON. SEAS 6 TO 8 FT.
FRI NIGHT
SE WINDS 10 TO 20 KT. SEAS 5 TO 7 FT.
SAT
SE WINDS 10 TO 20 KT. SEAS 5 TO 7 FT.
SAT NIGHT
SE WINDS 10 TO 15 KT. SEAS 6 TO 8 FT.
SUN
E WINDS 10 TO 15 KT. SEAS 6 TO 8 FT.
SUN NIGHT
E WINDS 10 TO 15 KT. SEAS 7 TO 8 FT.
MON
E WINDS 10 TO 15 KT. SEAS 8 FT.
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