Offshore Forecast
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858
FZNT31 KNHC 220144
OFFN20

Marine Weather HF Voice Broadcast
NWS National Hurricane Center Miami, FL
944 PM 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 strong trades and moderate seas, locally
rough, will exist over the central Caribbean through the next
several days as a strengthening pressure gradient develops
between low pressure over Colombia and building high pressure in
the wake of Hurricane Erin in the west Atlantic. Fresh to strong
east to southeast winds will pulse near the Gulf of Honduras at
night. Moderate to fresh trades will pulse in the eastern
Caribbean and across the approach to the Windward Passage with
moderate or weaker winds elsewhere. An area of disorganized
showers and thunderstorms associated with a tropical wave is
located a few hundred nautical 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

.OVERNIGHT...E winds 10 to 15 kt. Seas 2 ft or less, building to
3 ft after midnight.
.FRI...SE winds 10 to 15 kt. Seas 3 to 4 ft.
.FRI NIGHT...SE winds 10 to 20 kt. Seas 3 to 5 ft.
.SAT...E winds 10 to 20 kt. Seas 4 to 6 ft.
.SAT NIGHT...E winds 10 to 15 kt. Seas 3 to 5 ft.
.SUN...E winds 10 to 15 kt. Seas 3 to 5 ft.
.SUN NIGHT...E winds 10 to 15 kt. Seas 3 to 4 ft.
.MON...E winds 10 to 20 kt. Seas 3 to 5 ft.
.MON NIGHT...E winds 10 to 20 kt. Seas 3 to 5 ft.
.TUE...E winds 10 to 15 kt. Seas 3 to 5 ft.
.TUE NIGHT...E winds 10 to 15 kt. Seas 3 to 5 ft.

Caribbean N of 15N between 72W and 85W

.OVERNIGHT...S of 18N, E winds 10 to 20 kt. Elsewhere, E winds
less than 10 kt, increasing to 10 to 15 kt after midnight. Seas
4 to 6 ft S of 18N, and 3 ft elsewhere.
.FRI...E winds 10 to 20 kt. Seas 4 to 6 ft S of 18N, and 3 ft
elsewhere.
.FRI NIGHT...E winds 10 to 15 kt S of 18N, and E less than 10 kt
elsewhere. Seas 4 to 6 ft S of 18N, and 3 ft elsewhere.
.SAT...E winds 10 to 15 kt. Seas 3 to 5 ft.
.SAT NIGHT...E winds 10 to 15 kt. Seas 3 to 5 ft.
.SUN...E winds 10 to 15 kt. Seas 3 to 5 ft.
.SUN NIGHT...E winds 10 to 20 kt. Seas 3 to 5 ft.
.MON...E winds 10 to 20 kt. Seas 4 to 6 ft.
.MON NIGHT...E winds 10 to 20 kt. Seas 4 to 6 ft.
.TUE...E winds 10 to 20 kt. Seas 4 to 6 ft.
.TUE NIGHT...E winds 10 to 20 kt. Seas 4 to 6 ft.

Caribbean from 11N to 15N W of 72W

.OVERNIGHT...E winds 15 to 25 kt within 90 nm of coast of
Colombia, and E 10 to 20 kt elsewhere. Seas 5 to 7 ft.
.FRI...E winds 10 to 20 kt. Seas 5 to 7 ft.
.FRI NIGHT...E winds 10 to 15 kt. Seas 5 to 7 ft.
.SAT...E winds 10 to 15 kt. Seas 5 to 6 ft.
.SAT NIGHT...E winds 10 to 15 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.
.MON NIGHT...E winds 10 to 20 kt. Seas 5 to 7 ft.
.TUE...E winds 10 to 20 kt. Seas 6 to 8 ft.
.TUE NIGHT...NE winds 10 to 20 kt. Seas 6 to 8 ft.

SW Caribbean S of 11N

.OVERNIGHT...N winds less than 10 kt. Seas 3 to 5 ft.
.FRI...NW winds less than 10 kt, shifting to SW in the
afternoon. Seas 4 to 6 ft.
.FRI NIGHT...NW winds less than 10 kt. Seas 4 to 6 ft.
.SAT...SE winds less than 10 kt. Seas 3 to 5 ft.
.SAT NIGHT...SW winds less than 10 kt. Seas 3 to 5 ft.
.SUN...Variable winds less than 10 kt. Seas 3 to 4 ft.
.SUN NIGHT...Variable winds less than 10 kt. Seas 3 to 4 ft.
.MON...W winds less than 10 kt. Seas 3 to 5 ft.
.MON NIGHT...NW winds less than 10 kt, shifting to N after
midnight. Seas 4 to 6 ft.
.TUE...NE winds 10 to 15 kt. Seas 5 to 7 ft.
.TUE NIGHT...NE winds 10 to 15 kt. Seas 5 to 7 ft.

Caribbean between 64W and 72W

.OVERNIGHT...E winds 20 to 25 kt Gulf of Venezuela, and E 10 to
20 kt elsewhere. Seas 4 to 6 ft.
.FRI...E winds 10 to 20 kt. Seas 3 to 5 ft Gulf of Venezuela,
and 4 to 6 ft elsewhere.
.FRI NIGHT...NE winds 15 to 20 kt Gulf of Venezuela, and E 10 to
15 kt elsewhere. Seas 3 to 5 ft.
.SAT...NE winds 10 to 20 kt Gulf of Venezuela, and E 10 to 15 kt
elsewhere. Seas 3 to 5 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.
.MON NIGHT...E winds 10 to 20 kt. Seas 5 to 7 ft.
.TUE...E winds 10 to 20 kt. Seas 5 to 7 ft.
.TUE NIGHT...E winds 10 to 20 kt. Seas 5 to 7 ft.

Offshore Leeward Islands and adjacent ATLC waters from 15N to
19N W of 55W

.OVERNIGHT...E winds 10 to 15 kt. Seas 5 to 7 ft.
.FRI...SE winds 10 to 15 kt. Seas 4 to 6 ft.
.FRI NIGHT...SE winds less than 10 kt. Seas 4 to 6 ft.
.SAT...E winds 10 to 15 kt. Seas 4 to 6 ft.
.SAT NIGHT...E winds 10 to 15 kt. Seas 5 to 7 ft.
.SUN...E winds 10 to 15 kt. Seas 6 to 8 ft.
.SUN NIGHT...E winds 10 to 15 kt. Seas 6 to 9 ft.
.MON...E winds 10 to 15 kt. Seas 6 to 9 ft.
.MON NIGHT...E winds 10 to 15 kt. Seas 6 to 8 ft.
.TUE...E winds 10 to 15 kt. Seas 5 to 7 ft.
.TUE NIGHT...E winds less than 10 kt, increasing to 10 to 15 kt
after midnight. Seas 4 to 6 ft.

Offshore Windward Islands and adjacent ATLC waters from 07N to
15N W of 55W

.OVERNIGHT...SE winds 10 to 15 kt. Seas 4 to 6 ft.
.FRI...SE winds 10 to 15 kt. Seas 3 to 5 ft.
.FRI NIGHT...E winds 10 to 15 kt. Seas 4 to 6 ft.
.SAT...E winds 10 to 15 kt. Seas 4 to 6 ft.
.SAT NIGHT...E winds 10 to 15 kt. Seas 5 to 7 ft.
.SUN...E winds 10 to 15 kt. Seas 4 to 6 ft.
.SUN NIGHT...E winds 10 to 20 kt. Seas 5 to 7 ft.
.MON...E winds 10 to 15 kt. Seas 5 to 7 ft.
.MON NIGHT...E winds 10 to 15 kt. Seas 5 to 7 ft.
.TUE...E winds 10 to 15 kt. Seas 5 to 7 ft.
.TUE NIGHT...E winds 10 to 15 kt. Seas 4 to 6 ft.

Synopsis for the the SW N Atlantic including the Bahamas

.SYNOPSIS...Hurricane Erin is centered N of the area and
continues to move NNE away from the region. Despite its
distance, long period northerly swells generated by Erin will
continue to affect the W Atlantic waters 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.
An area of disorganized showers and thunderstorms associated with
a tropical wave is located a few hundred nautical 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. Regardless of development,
increasing winds and building seas will accompany the feature
across portions of the zones east of 70W.

ATLC waters from 27N to 31N W of 77W

.OVERNIGHT...Variable winds less than 10 kt, becoming SW less
than 10 kt after midnight. Seas 6 to 8 ft.
.FRI...W winds less than 10 kt. Seas 6 to 8 ft.
.FRI NIGHT...Variable winds less than 10 kt, becoming S less
than 10 kt after midnight. Seas 6 to 8 ft.
.SAT...Variable winds less than 10 kt, becoming SW less than
10 kt in the afternoon. Seas 5 to 7 ft.
.SAT NIGHT...Variable winds less than 10 kt, becoming SW 10 kt
after midnight. Seas 5 to 7 ft.
.SUN...SW winds 10 to 15 kt. Seas 5 to 7 ft.
.SUN NIGHT...SW winds 10 to 15 kt. Seas 5 to 7 ft.
.MON...W winds 10 to 15 kt. Seas 5 to 7 ft.
.MON NIGHT...SW winds less than 10 kt. Seas 4 to 6 ft.
.TUE...SW winds less than 10 kt. Seas 4 to 5 ft.
.TUE NIGHT...SW winds less than 10 kt. Seas 3 to 4 ft.

ATLC waters from 27N to 31N between 65W and 77W

.OVERNIGHT...W winds 10 to 20 kt W of 70W, and SW 15 to 25 kt
elsewhere. Seas 9 to 14 ft.
.FRI...W winds less than 10 kt W of 70W, and W 10 to 20 kt
elsewhere. Seas 8 to 11 ft W of 70W, and 9 to 14 ft elsewhere.
.FRI NIGHT...W of 70W, NW winds less than 10 kt in the evening,
becoming variable winds less than 10 kt. Elsewhere, W winds
10 to 15 kt, diminishing to less than 10 kt after midnight. Seas
8 to 11 ft W of 70W, and 8 to 13 ft elsewhere.
.SAT...Variable winds less than 10 kt. Seas 8 to 11 ft.
.SAT NIGHT...Variable winds less than 10 kt, becoming S less
than 10 kt after midnight. Seas 7 to 10 ft.
.SUN...S winds less than 10 kt, increasing to 10 to 15 kt in the
afternoon. Seas 7 to 9 ft.
.SUN NIGHT...SW winds 10 to 15 kt. Seas 7 to 8 ft.
.MON...SW winds 10 to 15 kt. Seas 6 to 7 ft.
.MON NIGHT...SW winds 10 to 15 kt. Seas 5 to 7 ft.
.TUE...SW winds 10 to 15 kt. Seas 5 to 7 ft.
.TUE NIGHT...SW winds 10 to 15 kt, diminishing to less than
10 kt after midnight. Seas 4 to 6 ft.

Bahamas N of 22N

.OVERNIGHT...Variable winds less than 10 kt, becoming S less
than 10 kt after midnight. Seas 3 to 5 ft.
.FRI...S winds less than 10 kt in the morning, becoming variable
winds less than 10 kt. Seas 3 ft.
.FRI NIGHT...Variable winds less than 10 kt, becoming E less
than 10 kt after midnight. Seas 3 to 5 ft.
.SAT...SE winds less than 10 kt in the morning, becoming
variable winds less than 10 kt. Seas 3 to 5 ft.
.SAT NIGHT...SE winds less than 10 kt. Seas 3 to 4 ft.
.SUN...SE winds less than 10 kt. Seas 3 to 5 ft.
.SUN NIGHT...SE winds less than 10 kt. Seas 3 to 5 ft.
.MON...SE winds less than 10 kt. Seas 3 to 5 ft.
.MON NIGHT...SE winds less than 10 kt, increasing to 10 to 15 kt
after midnight. Seas 3 to 4 ft.
.TUE...SE winds 10 to 15 kt. Seas 3 to 4 ft.
.TUE NIGHT...E winds 10 to 15 kt. Seas 3 to 4 ft.

ATLC waters from 22N to 27N between 65W and the Bahamas

.OVERNIGHT...S winds less than 10 kt. Seas 6 to 8 ft.
.FRI...S winds less than 10 kt. Seas 5 to 7 ft.
.FRI NIGHT...NW winds less than 10 kt, shifting to E after
midnight. Seas 6 to 8 ft.
.SAT...SE winds less than 10 kt in the morning, becoming
variable winds less than 10 kt. Seas 6 to 9 ft.
.SAT NIGHT...E winds less than 10 kt. Seas 7 to 9 ft.
.SUN...S winds less than 10 kt. Seas 7 to 8 ft.
.SUN NIGHT...S winds less than 10 kt. Seas 6 to 8 ft.
.MON...S winds 10 kt. Seas 6 to 7 ft.
.MON NIGHT...SE winds less than 10 kt. Seas 5 to 7 ft.
.TUE...SE winds less than 10 kt. Seas 4 to 6 ft.
.TUE NIGHT...E winds less than 10 kt, increasing to 10 to 15 kt
after midnight. Seas 4 to 6 ft.

ATLC waters S of 22N W of 65W

.OVERNIGHT...E winds 10 to 15 kt. Seas 3 to 5 ft.
.FRI...E winds 10 to 15 kt, diminishing to less than 10 kt in
the afternoon. Seas 3 to 5 ft.
.FRI NIGHT...NE winds 10 to 15 kt. Seas 3 to 5 ft.
.SAT...E winds less than 10 kt. Seas 4 to 6 ft.
.SAT NIGHT...E winds 10 to 15 kt. Seas 4 to 6 ft.
.SUN...SE winds 10 to 15 kt, shifting to E in the afternoon.
Seas 4 to 6 ft.
.SUN NIGHT...E winds 10 to 15 kt. Seas 4 to 6 ft.
.MON...E winds 10 to 15 kt. Seas 4 to 6 ft.
.MON NIGHT...E winds 10 to 15 kt. Seas 4 to 6 ft.
.TUE...E winds 10 to 15 kt. Seas 5 to 7 ft.
.TUE NIGHT...E winds 10 to 15 kt. Seas 5 to 7 ft.

ATLC waters from 19N to 22N between 55W and 65W

.OVERNIGHT...E winds 10 to 15 kt. Seas 6 to 7 ft.
.FRI...E winds 10 to 15 kt. Seas 6 to 8 ft.
.FRI NIGHT...SE winds 10 to 15 kt. Seas 6 to 7 ft.
.SAT...SE winds 10 to 15 kt. Seas 5 to 7 ft.
.SAT NIGHT...SE winds 10 to 15 kt. Seas 6 to 7 ft.
.SUN...E winds 10 to 15 kt. Seas 7 to 8 ft.
.SUN NIGHT...E winds 10 to 15 kt. Seas 7 to 8 ft.
.MON...E winds 10 to 15 kt. Seas 7 to 8 ft.
.MON NIGHT...E winds 10 to 15 kt. Seas 7 to 8 ft.
.TUE...E winds 10 to 15 kt. Seas 6 to 7 ft.
.TUE NIGHT...E winds 10 to 15 kt. Seas 5 to 7 ft.