461
FZUS51 KBOX 242005
CWFBOX

Coastal Waters Forecast for Massachusetts and Rhode Island
National Weather Service Boston/Norton MA
404 PM EDT Sun Aug 24 2025

Coastal waters from the Merrimack River MA to Watch Hill RI out
to 25 NM

ANZ200-250900-
404 PM EDT Sun Aug 24 2025

.Synopsis for Massachusetts and Rhode Island coastal waters...
Seas will gradually trend downward tonight through Monday. Breezy
southeast winds shift northeast Monday ahead of a cold front
expected to pass over the waters by the afternoon/evening. High
pressure builds in from the west on Tuesday and remains in control
through midweek.

$$

ANZ250-250900-
Coastal waters east of Ipswich Bay and the Stellwagen Bank
National Marine Sanctuary-
404 PM EDT Sun Aug 24 2025

...SMALL CRAFT ADVISORY IN EFFECT UNTIL 2 AM EDT MONDAY...

.TONIGHT...S winds 15 to 20 kt, diminishing to around 10 kt after
midnight. Gusts up to 25 kt. Seas 4 to 6 ft. Wave Detail: S 4 ft
at 5 seconds and E 3 ft at 10 seconds. Patchy fog after midnight.
A slight chance of showers after midnight with vsby 1 to 3 NM.
.MON...SE winds around 10 kt. Gusts up to 20 kt in the morning.
Seas 2 to 3 ft. Wave Detail: SE 3 ft at 7 seconds and SW 1 foot
at 3 seconds. Patchy fog in the morning. A chance of showers in
the morning with vsby 1 to 3 NM.
.MON NIGHT...S winds around 10 kt, becoming W with gusts up to
20 kt after midnight. Seas 3 to 5 ft. Wave Detail: SE 5 ft at
9 seconds and W 2 ft at 3 seconds.
.TUE...W winds 10 to 15 kt with gusts up to 20 kt, becoming SW in
the afternoon. Seas 3 to 5 ft. Wave Detail: SE 4 ft at 8 seconds
and W 2 ft at 3 seconds.
.TUE NIGHT...W winds around 10 kt with gusts up to 20 kt,
becoming NW after midnight. Seas 2 to 3 ft. Wave Detail: SE 3 ft
at 9 seconds and W 2 ft at 3 seconds.
.WED AND WED NIGHT...W winds 5 to 10 kt. Seas 2 to 3 ft. Wave
Detail: SE 3 ft at 9 seconds and NW 2 ft at 3 seconds.
.THU THROUGH FRI NIGHT...SW winds 10 to 15 kt with gusts up to
25 kt. Seas 2 to 3 ft.

Seas are reported as significant wave height, which is the
average of the highest third of the waves. Individual wave
heights may be more than twice the significant wave height.

$$

ANZ251-250900-
Massachusetts Bay and Ipswich Bay-
404 PM EDT Sun Aug 24 2025

...SMALL CRAFT ADVISORY IN EFFECT UNTIL 10 PM EDT THIS EVENING...

.TONIGHT...S winds 15 to 20 kt with gusts up to 25 kt,
diminishing to around 10 kt after midnight. Seas 3 to 5 ft. Wave
Detail: S 4 ft at 5 seconds and E 3 ft at 11 seconds. Patchy fog
after midnight. A slight chance of showers after midnight with
vsby 1 to 3 NM.
.MON...SE winds around 10 kt. Seas 2 to 3 ft. Wave Detail: E 3 ft
at 10 seconds and S 1 foot at 3 seconds. Patchy fog in the
morning. A chance of showers in the morning with vsby 1 to 3 NM.
.MON NIGHT...SW winds 5 to 10 kt, becoming W after midnight. Seas
2 to 3 ft. Wave Detail: E 3 ft at 7 seconds and SW 1 foot at
2 seconds.
.TUE...W winds 10 to 15 kt. Gusts up to 20 kt in the afternoon.
Seas 2 to 3 ft. Wave Detail: E 3 ft at 8 seconds and W 2 ft at
3 seconds.
.TUE NIGHT...W winds around 10 kt. Seas around 2 ft. Wave Detail:
W 2 ft at 3 seconds and E 2 ft at 7 seconds.
.WED AND WED NIGHT...W winds 5 to 10 kt. Seas around 2 ft. Wave
Detail: E 2 ft at 9 seconds and NW 1 foot at 3 seconds.
.THU THROUGH FRI NIGHT...SW winds 10 to 15 kt with gusts up to
20 kt. Seas around 2 ft.

Seas are reported as significant wave height, which is the
average of the highest third of the waves. Individual wave
heights may be more than twice the significant wave height.

$$

ANZ231-250900-
Cape Cod Bay-
404 PM EDT Sun Aug 24 2025

.TONIGHT...S winds 10 to 15 kt. Gusts up to 20 kt this evening.
Seas 2 to 4 ft. Wave Detail: S 2 ft at 4 seconds and E 2 ft at
11 seconds. Patchy fog after midnight. A chance of showers after
midnight with vsby 1 to 3 NM.
.MON...E winds around 10 kt. Gusts up to 20 kt in the morning.
Seas around 2 ft. Wave Detail: SE 1 foot at 3 seconds and E
1 foot at 12 seconds. Patchy fog in the morning. A chance of
showers in the morning with vsby 1 to 3 NM.
.MON NIGHT...SW winds around 10 kt, becoming W after midnight.
Seas around 2 ft. Wave Detail: E 2 ft at 5 seconds and SW 1 foot
at 2 seconds.
.TUE...W winds 10 to 15 kt. Gusts up to 20 kt in the afternoon.
Seas around 2 ft. Wave Detail: SE 2 ft at 7 seconds and W 1 foot
at 3 seconds.
.TUE NIGHT...SW winds 10 to 15 kt with gusts up to 20 kt,
becoming NW 5 to 10 kt after midnight. Seas around 2 ft. Wave
Detail: SE 2 ft at 7 seconds and W 1 foot at 3 seconds.
.WED AND WED NIGHT...W winds 5 to 10 kt. Seas around 2 ft. Wave
Detail: SE 2 ft at 8 seconds and NW 1 foot at 3 seconds.
.THU THROUGH FRI NIGHT...SW winds 10 to 15 kt with gusts up to
20 kt. Seas around 2 ft.

Seas are reported as significant wave height, which is the
average of the highest third of the waves. Individual wave
heights may be more than twice the significant wave height.

$$

ANZ254-250900-
Coastal waters from Provincetown MA to Chatham MA to Nantucket MA
out 20 nm-
404 PM EDT Sun Aug 24 2025

...SMALL CRAFT ADVISORY IN EFFECT UNTIL 2 AM EDT MONDAY...

.TONIGHT...SE winds 10 to 15 kt with gusts up to 20 kt. Seas 4 to
6 ft. Wave Detail: S 4 ft at 5 seconds and E 4 ft at 11 seconds.
Patchy fog after midnight. A chance of showers after midnight
with vsby 1 to 3 NM.
.MON...E winds 15 to 20 kt, becoming N 10 to 15 kt in the
afternoon. Gusts up to 25 kt. Seas 3 to 4 ft, building to 4 to
6 ft in the afternoon. Wave Detail: E 4 ft at 7 seconds and E
2 ft at 13 seconds, becoming E 5 ft at 7 seconds and E 1 foot at
13 seconds. Patchy fog in the morning. A chance of showers in the
morning with vsby 1 to 3 NM.
.MON NIGHT...SW winds 10 to 15 kt. Seas 4 to 6 ft. Wave Detail:
SE 6 ft at 8 seconds and SW 1 foot at 3 seconds. Patchy fog after
midnight with vsby 1 to 3 NM.
.TUE...W winds 10 to 15 kt. Gusts up to 20 kt in the afternoon.
Seas 3 to 5 ft. Wave Detail: SE 5 ft at 8 seconds and W 1 foot at
3 seconds.
.TUE NIGHT THROUGH WED NIGHT...W winds 10 to 15 kt with gusts up
to 20 kt. Seas 2 to 4 ft. Wave Detail: S 3 ft at 8 seconds and W
2 ft at 4 seconds.
.THU THROUGH FRI NIGHT...SW winds 10 to 15 kt with gusts up to
20 kt. Seas 2 to 3 ft. Wave Detail: SE 3 ft at 8 seconds and SW
2 ft at 3 seconds.

Seas are reported as significant wave height, which is the
average of the highest third of the waves. Individual wave
heights may be more than twice the significant wave height.

$$

ANZ255-250900-
Coastal Waters extending out to 25 nm South of Marthas Vineyard
and Nantucket-
404 PM EDT Sun Aug 24 2025

...SMALL CRAFT ADVISORY IN EFFECT UNTIL 2 AM EDT MONDAY...

.TONIGHT...SE winds 10 to 15 kt. Gusts up to 20 kt after
midnight. Seas 3 to 5 ft. Wave Detail: S 3 ft at 4 seconds and E
3 ft at 11 seconds. Patchy fog after midnight. Showers likely
after midnight with vsby 1 to 3 NM.
.MON...NE winds around 15 kt, becoming W in the afternoon. Gusts
up to 20 kt. Seas 3 to 4 ft, building to 4 to 6 ft in the
afternoon. Wave Detail: SE 4 ft at 6 seconds and E 2 ft at
10 seconds, becoming SE 6 ft at 8 seconds and NW 1 foot at
3 seconds. Patchy fog in the morning. A chance of showers in the
morning with vsby 1 to 3 NM.
.MON NIGHT...W winds 10 to 15 kt. Gusts up to 20 kt in the
evening. Seas 4 to 6 ft. Wave Detail: S 6 ft at 8 seconds and SW
1 foot at 3 seconds. Patchy fog after midnight with vsby 1 to
3 NM.
.TUE...W winds 10 to 15 kt. Gusts up to 20 kt in the afternoon.
Seas 3 to 5 ft. Wave Detail: S 5 ft at 8 seconds and W 2 ft at
4 seconds.
.TUE NIGHT THROUGH WED NIGHT...W winds 10 to 15 kt with gusts up
to 20 kt. Seas 2 to 4 ft. Wave Detail: S 3 ft at 7 seconds and SW
2 ft at 4 seconds.
.THU THROUGH FRI NIGHT...SW winds 10 to 15 kt with gusts up to
20 kt. Seas 2 to 3 ft. Wave Detail: SW 3 ft at 5 seconds and SE
2 ft at 8 seconds.

Seas are reported as significant wave height, which is the
average of the highest third of the waves. Individual wave
heights may be more than twice the significant wave height.

$$

ANZ256-250900-
Coastal Waters from Montauk NY to Marthas Vineyard extending out
to 20 nm South of Block Island-
404 PM EDT Sun Aug 24 2025

...SMALL CRAFT ADVISORY IN EFFECT UNTIL 2 AM EDT MONDAY...

.TONIGHT...SE winds 10 to 15 kt. Seas 3 to 5 ft. Wave Detail: E
4 ft at 11 seconds and S 3 ft at 7 seconds. A chance of showers
after midnight.
.MON...NE winds 10 to 15 kt, becoming W in the afternoon. Gusts
up to 20 kt. Seas 3 to 5 ft. Wave Detail: SE 5 ft at 9 seconds
and E 2 ft at 11 seconds. Patchy fog in the morning. A chance of
showers in the morning with vsby 1 to 3 NM.
.MON NIGHT...SW winds 10 to 15 kt with gusts up to 20 kt,
becoming NW after midnight. Seas 4 to 6 ft. Wave Detail: S 6 ft
at 8 seconds and SW 1 foot at 3 seconds. Patchy fog. Vsby 1 to
3 NM, decreasing to 1 NM or less after midnight.
.TUE...NW winds around 10 kt, becoming W with gusts up to 20 kt
in the afternoon. Seas 4 to 5 ft. Wave Detail: SE 5 ft at
8 seconds and W 1 foot at 3 seconds.
.TUE NIGHT...SW winds 10 to 15 kt with gusts up to 20 kt,
becoming NW after midnight. Seas 3 to 4 ft. Wave Detail: S 4 ft
at 7 seconds and SW 2 ft at 4 seconds.
.WED AND WED NIGHT...W winds 10 to 15 kt. Seas around 3 ft. Wave
Detail: SE 3 ft at 8 seconds and NW 2 ft at 3 seconds.
.THU THROUGH FRI NIGHT...SW winds 10 to 15 kt with gusts up to
20 kt. Seas 2 to 3 ft.

Seas are reported as significant wave height, which is the
average of the highest third of the waves. Individual wave
heights may be more than twice the significant wave height.

$$

ANZ232-250900-
Nantucket Sound-
404 PM EDT Sun Aug 24 2025

.TONIGHT...S winds 10 to 15 kt. Gusts up to 20 kt this evening.
Seas 2 to 4 ft. Wave Detail: S 2 ft at 4 seconds and E 2 ft at
11 seconds. Patchy fog after midnight. A chance of showers after
midnight with vsby 1 to 3 NM.
.MON...NE winds around 15 kt, becoming W in the afternoon. Gusts
up to 20 kt. Seas 2 to 3 ft. Wave Detail: E 3 ft at 4 seconds and
SW 1 foot at 4 seconds. Patchy fog in the morning. A chance of
showers in the morning with vsby 1 to 3 NM.
.MON NIGHT...W winds 10 to 15 kt. Gusts up to 20 kt in the
evening. Seas 2 to 3 ft. Wave Detail: SW 2 ft at 3 seconds and SE
2 ft at 8 seconds. Patchy fog after midnight with vsby 1 to 3 NM.
.TUE...W winds 10 to 15 kt. Gusts up to 20 kt in the afternoon.
Seas 2 to 3 ft. Wave Detail: W 2 ft at 3 seconds and SE 2 ft at
8 seconds.
.TUE NIGHT THROUGH WED NIGHT...W winds 10 to 15 kt with gusts up
to 20 kt. Seas 2 to 3 ft. Wave Detail: SW 3 ft at 4 seconds and
SE 1 foot at 7 seconds.
.THU THROUGH FRI NIGHT...SW winds 10 to 15 kt with gusts up to
20 kt. Seas around 2 ft. Wave Detail: SW 2 ft at 3 seconds and SE
1 foot at 8 seconds.

Seas are reported as significant wave height, which is the
average of the highest third of the waves. Individual wave
heights may be more than twice the significant wave height.

$$

ANZ233-250900-
Vineyard Sound-
404 PM EDT Sun Aug 24 2025

.TONIGHT...SE winds 10 to 15 kt. Seas 2 to 3 ft. Wave Detail: S
2 ft at 5 seconds and E 1 foot at 12 seconds. Patchy fog after
midnight. A chance of showers after midnight.
.MON...NE winds 10 to 15 kt, becoming SW with gusts up to 20 kt
in the afternoon. Seas 2 to 3 ft. Wave Detail: E 2 ft at
4 seconds and SW 1 foot at 4 seconds. Patchy fog in the morning.
A chance of showers in the morning with vsby 1 to 3 NM.
.MON NIGHT...SW winds 10 to 15 kt with gusts up to 20 kt,
becoming W after midnight. Seas 2 to 3 ft. Wave Detail: S 3 ft at
8 seconds and SW 2 ft at 4 seconds. Patchy fog. Vsby 1 to 3 NM,
decreasing to 1 NM or less after midnight.
.TUE...W winds around 10 kt, becoming SW with gusts up to 20 kt
in the afternoon. Seas 2 to 3 ft. Wave Detail: SW 2 ft at
4 seconds and S 2 ft at 8 seconds.
.TUE NIGHT...SW winds 10 to 15 kt with gusts up to 20 kt,
becoming NW after midnight. Seas 2 to 3 ft. Wave Detail: SW 2 ft
at 4 seconds and S 2 ft at 7 seconds.
.WED AND WED NIGHT...W winds 5 to 10 kt. Seas around 2 ft. Wave
Detail: SW 2 ft at 4 seconds and S 2 ft at 8 seconds.
.THU THROUGH FRI NIGHT...SW winds 10 to 15 kt with gusts up to
20 kt. Seas 2 to 3 ft.

Seas are reported as significant wave height, which is the
average of the highest third of the waves. Individual wave
heights may be more than twice the significant wave height.

$$

ANZ234-250900-
Buzzards Bay-
404 PM EDT Sun Aug 24 2025

.TONIGHT...S winds 10 to 15 kt. Gusts up to 20 kt this evening.
Seas 2 to 3 ft. Wave Detail: S 2 ft at 4 seconds and E 2 ft at
12 seconds. Patchy fog after midnight. A chance of showers after
midnight with vsby 1 to 3 NM.
.MON...NE winds around 10 kt, becoming SW with gusts up to 20 kt
in the afternoon. Seas around 2 ft. Wave Detail: E 1 foot at
3 seconds and SW 1 foot at 4 seconds. Patchy fog in the morning.
A chance of showers in the morning with vsby 1 to 3 NM.
.MON NIGHT...SW winds 10 to 15 kt with gusts up to 20 kt,
becoming W after midnight. Seas 2 to 3 ft. Wave Detail: SW 2 ft
at 4 seconds and S 2 ft at 8 seconds. Patchy fog. Vsby 1 to 3 NM,
decreasing to 1 NM or less after midnight.
.TUE...W winds around 10 kt, becoming SW 15 to 20 kt in the
afternoon. Seas 2 to 3 ft. Wave Detail: SW 2 ft at 4 seconds and
S 2 ft at 8 seconds.
.TUE NIGHT...SW winds 10 to 15 kt with gusts up to 20 kt,
becoming NW 5 to 10 kt after midnight. Seas 2 to 3 ft. Wave
Detail: SW 2 ft at 4 seconds and S 1 foot at 7 seconds.
.WED AND WED NIGHT...W winds 10 to 15 kt. Seas around 2 ft. Wave
Detail: NW 1 foot at 3 seconds and S 1 foot at 7 seconds.
.THU THROUGH FRI NIGHT...SW winds 10 to 15 kt with gusts up to
20 kt. Seas 2 to 3 ft.

Seas are reported as significant wave height, which is the
average of the highest third of the waves. Individual wave
heights may be more than twice the significant wave height.

$$

ANZ235-250900-
Rhode Island Sound-
404 PM EDT Sun Aug 24 2025

.TONIGHT...SE winds 10 to 15 kt. Seas 2 to 4 ft. Wave Detail: S
3 ft at 4 seconds and E 1 foot at 13 seconds. Patchy fog after
midnight. A chance of showers after midnight with vsby 1 to 3 NM.
.MON...NE winds around 10 kt, becoming SW with gusts up to 20 kt
in the afternoon. Seas 2 to 4 ft. Wave Detail: SE 4 ft at
9 seconds and SW 1 foot at 3 seconds. Patchy fog in the morning.
A chance of showers in the morning with vsby 1 to 3 NM.
.MON NIGHT...SW winds 10 to 15 kt with gusts up to 20 kt,
becoming W after midnight. Seas 3 to 5 ft. Wave Detail: S 5 ft at
9 seconds and SW 1 foot at 3 seconds. Patchy fog. Vsby 1 to 3 NM,
decreasing to 1 NM or less after midnight.
.TUE...W winds around 10 kt, becoming SW with gusts up to 20 kt
in the afternoon. Seas 3 to 4 ft. Wave Detail: S 4 ft at
8 seconds and SW 3 ft at 4 seconds.
.TUE NIGHT...W winds 10 to 15 kt with gusts up to 20 kt, becoming
NW after midnight. Seas 2 to 4 ft. Wave Detail: SW 3 ft at
4 seconds and S 3 ft at 7 seconds.
.WED AND WED NIGHT...W winds 10 to 15 kt. Seas 2 to 3 ft. Wave
Detail: S 3 ft at 8 seconds and W 2 ft at 3 seconds.
.THU THROUGH FRI NIGHT...SW winds 10 to 15 kt with gusts up to
20 kt. Seas 2 to 3 ft.

Seas are reported as significant wave height, which is the
average of the highest third of the waves. Individual wave
heights may be more than twice the significant wave height.

$$

ANZ237-250900-
Block Island Sound-
404 PM EDT Sun Aug 24 2025

.TONIGHT...SE winds 5 to 10 kt. Seas 2 to 4 ft. Wave Detail: E
3 ft at 12 seconds and S 2 ft at 7 seconds. Patchy fog after
midnight. A chance of showers after midnight.
.MON...NE winds 5 to 10 kt, becoming SW 10 to 15 kt with gusts up
to 20 kt in the afternoon. Seas 2 to 3 ft. Wave Detail: SE 3 ft
at 7 seconds and E 1 foot at 12 seconds. Patchy fog in the
morning. A chance of showers in the morning with vsby 1 to 3 NM.
.MON NIGHT...SW winds 10 to 15 kt with gusts up to 20 kt,
becoming NW after midnight. Seas 3 to 5 ft. Wave Detail: S 5 ft
at 8 seconds and SW 1 foot at 3 seconds.
.TUE...W winds around 10 kt, becoming SW with gusts up to 20 kt
in the afternoon. Seas 3 to 4 ft. Wave Detail: SE 4 ft at
8 seconds and W 2 ft at 3 seconds.
.TUE NIGHT...W winds 10 to 15 kt with gusts up to 20 kt, becoming
NW after midnight. Seas 2 to 3 ft. Wave Detail: SE 3 ft at
7 seconds and W 2 ft at 4 seconds.
.WED AND WED NIGHT...W winds 5 to 10 kt. Seas 2 to 3 ft. Wave
Detail: SE 2 ft at 8 seconds and NW 1 foot at 3 seconds.
.THU THROUGH FRI NIGHT...W winds 10 to 15 kt with gusts up to
20 kt. Seas 2 to 3 ft.

Seas are reported as significant wave height, which is the
average of the highest third of the waves. Individual wave
heights may be more than twice the significant wave height.

$$

ANZ230-250900-
Boston Harbor-
404 PM EDT Sun Aug 24 2025

.TONIGHT...S winds 10 to 15 kt with gusts up to 20 kt, becoming
SE 5 to 10 kt after midnight. Waves around 2 ft this evening,
then 1 foot or less. Patchy fog after midnight. A slight chance
of showers after midnight with vsby 1 to 3 NM.
.MON...SE winds 5 to 10 kt. Waves 1 foot or less. A chance of
showers. Patchy fog in the morning with vsby 1 to 3 NM.
.MON NIGHT...SW winds 5 to 10 kt, becoming W after midnight.
Waves 1 foot or less.
.TUE...W winds 10 to 15 kt. Gusts up to 20 kt in the afternoon.
Waves around 2 ft.
.TUE NIGHT...W winds 10 to 15 kt, becoming NW 5 to 10 kt after
midnight. Waves around 2 ft in the evening, then 1 foot or less.
.WED AND WED NIGHT...W winds 5 to 10 kt. Waves 1 foot or less.
.THU THROUGH FRI NIGHT...SW winds 10 to 15 kt. Waves around 2 ft.


Seas are reported as significant wave height, which is the
average of the highest third of the waves. Individual wave
heights may be more than twice the significant wave height.

$$

ANZ236-250900-
Narragansett Bay-
404 PM EDT Sun Aug 24 2025

.TONIGHT...S winds 10 to 15 kt with gusts up to 20 kt, becoming
SE 5 to 10 kt after midnight. Waves 2 to 3 ft. Patchy fog after
midnight. A chance of showers after midnight with vsby 1 to 3 NM.
.MON...NE winds 5 to 10 kt, becoming SW in the afternoon. Waves
around 2 ft. Patchy fog in the morning. A chance of showers in
the morning with vsby 1 to 3 NM.
.MON NIGHT...SW winds around 10 kt, becoming NW after midnight.
Waves 2 to 3 ft.
.TUE...W winds 5 to 10 kt, becoming SW 10 to 15 kt with gusts up
to 20 kt in the afternoon. Waves 2 to 3 ft.
.TUE NIGHT...W winds 10 to 15 kt, becoming NW 5 to 10 kt after
midnight. Waves around 2 ft.
.WED AND WED NIGHT...W winds 5 to 10 kt. Waves around 2 ft.
.THU THROUGH FRI NIGHT...W winds 10 to 15 kt with gusts up to
20 kt. Waves around 2 ft.

Seas are reported as significant wave height, which is the
average of the highest third of the waves. Individual wave
heights may be more than twice the significant wave height.

$$

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