677
FZUS51 KBOX 291105
CWFBOX

Coastal Waters Forecast for Massachusetts and Rhode Island
National Weather Service Boston/Norton MA
704 AM EDT Fri Aug 29 2025

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

ANZ200-300000-
704 AM EDT Fri Aug 29 2025

.Synopsis for Massachusetts and Rhode Island coastal waters...
High pressure provides tranquil weather for the MA and RI waters
through Friday morning. A cold front approaches Southern New England
Friday evening and will be accompanied by scattered showers and
thunderstorms. The front exits offshore late Friday night, followed
by high pressure building back into the region for the holiday
weekend and possibly lingering into much of next week. This will
provide an extended period of tranquil boating conditions.

$$

ANZ250-300000-
Coastal waters east of Ipswich Bay and the Stellwagen Bank
National Marine Sanctuary-
704 AM EDT Fri Aug 29 2025

.TODAY...S winds 10 to 15 kt with gusts up to 25 kt. Seas 2 to
3 ft. Wave Detail: S 3 ft at 5 seconds. A chance of showers with
isolated tstms this afternoon. Some tstms may produce gusty
winds, small hail, and heavy rainfall this afternoon.
.TONIGHT...S winds 10 to 15 kt, becoming W after midnight. Gusts
up to 20 kt. Seas 2 to 3 ft. Wave Detail: S 3 ft at 5 seconds.
Showers likely, mainly in the evening.
.SAT...NW winds around 10 kt with gusts up to 20 kt, becoming W
in the afternoon. Seas around 2 ft. Wave Detail: NW 2 ft at
3 seconds and SE 2 ft at 6 seconds.
.SAT NIGHT...SW winds 5 to 10 kt, becoming NW after midnight.
Seas around 2 ft. Wave Detail: SE 2 ft at 8 seconds and SW 1 foot
at 3 seconds.
.SUN...NW winds 5 to 10 kt, becoming NE in the afternoon. Seas
around 2 ft. Wave Detail: SE 2 ft at 8 seconds and N 1 foot at
3 seconds.
.SUN NIGHT...S winds around 5 kt, becoming NW after midnight.
Seas around 2 ft. Wave Detail: E 2 ft at 8 seconds and N 1 foot
at 3 seconds.
.MON THROUGH TUE NIGHT...S winds 5 to 10 kt. Seas 2 to 3 ft.

Winds and seas higher in and near tstms.

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.

$$

ANZ251-300000-
Massachusetts Bay and Ipswich Bay-
704 AM EDT Fri Aug 29 2025

.TODAY...S winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to
3 ft. Wave Detail: SE 3 ft at 4 seconds. A slight chance of
showers this morning, then a chance of showers with isolated
tstms this afternoon. Some tstms may produce gusty winds, small
hail, and heavy rainfall this afternoon.
.TONIGHT...SW winds 5 to 10 kt, becoming W after midnight. Seas
around 2 ft. Wave Detail: SE 2 ft at 5 seconds. Showers in the
evening.
.SAT...NW winds 5 to 10 kt with gusts up to 20 kt, becoming SW in
the afternoon. Seas around 2 ft. Wave Detail: NW 1 foot at
3 seconds and E 1 foot at 4 seconds.
.SAT NIGHT...SW winds 5 to 10 kt, becoming NW after midnight.
Seas around 2 ft. Wave Detail: SW 1 foot at 2 seconds and E
1 foot at 3 seconds.
.SUN...NW winds 5 to 10 kt, becoming E in the afternoon. Seas
around 2 ft. Wave Detail: E 2 ft at 8 seconds and N 1 foot at
3 seconds.
.SUN NIGHT...S winds 5 to 10 kt, becoming W after midnight. Seas
around 2 ft. Wave Detail: E 2 ft at 8 seconds and NW 1 foot at
2 seconds.
.MON THROUGH TUE NIGHT...S winds 5 to 10 kt. Seas around 2 ft.

Winds and seas higher in and near tstms.

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.

$$

ANZ231-300000-
Cape Cod Bay-
704 AM EDT Fri Aug 29 2025

.TODAY...S winds 5 to 10 kt, increasing to 10 to 15 kt with gusts
up to 20 kt this afternoon. Seas 2 to 3 ft. Wave Detail: SE 2 ft
at 5 seconds and S 1 foot at 2 seconds. A slight chance of
showers with isolated tstms this afternoon. Some tstms may
produce gusty winds, small hail, and heavy rainfall this
afternoon.
.TONIGHT...S winds 5 to 10 kt with gusts up to 20 kt, becoming W
after midnight. Seas around 2 ft. Wave Detail: SE 2 ft at
6 seconds and S 1 foot at 3 seconds. Showers likely, mainly in
the evening.
.SAT...NW winds 5 to 10 kt. Gusts up to 20 kt in the morning.
Seas around 2 ft in the morning, then 1 foot or less. Wave
Detail: E 1 foot at 3 seconds and NW 1 foot at 3 seconds,
becoming NW 1 foot at 3 seconds and SE 1 foot at 7 seconds.
.SAT NIGHT...SW winds 5 to 10 kt, becoming NW after midnight.
Seas 1 foot or less. Wave Detail: NE 1 foot at 3 seconds and SW
1 foot at 3 seconds.
.SUN...NW winds 5 to 10 kt, becoming NE in the afternoon. Seas
1 foot or less. Wave Detail: N 1 foot at 3 seconds and SE 1 foot
at 8 seconds.
.SUN NIGHT...SE winds around 5 kt, becoming NW after midnight.
Seas 1 foot or less. Wave Detail: N 1 foot at 3 seconds and E
1 foot at 8 seconds.
.MON THROUGH TUE NIGHT...SE winds 5 to 10 kt. Seas 1 foot or
less.

Winds and seas higher in and near tstms.

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.

$$

ANZ254-300000-
Coastal waters from Provincetown MA to Chatham MA to Nantucket MA
out 20 nm-
704 AM EDT Fri Aug 29 2025

.TODAY...S winds 10 to 15 kt with gusts up to 25 kt. Seas 2 to
3 ft. Wave Detail: SE 3 ft at 7 seconds and SW 2 ft at 4 seconds.
A slight chance of showers this afternoon.
.TONIGHT...S winds 5 to 10 kt with gusts up to 20 kt, becoming SW
after midnight. Seas around 2 ft. Wave Detail: S 2 ft at
6 seconds. Patchy fog after midnight. A chance of showers after
midnight.
.SAT...W winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: S 2 ft at
6 seconds and W 1 foot at 3 seconds.
.SAT NIGHT...SW winds 5 to 10 kt with gusts up to 20 kt, becoming
NW after midnight. Seas 2 to 3 ft. Wave Detail: SE 2 ft at
7 seconds and W 1 foot at 3 seconds.
.SUN AND SUN NIGHT...N winds 5 to 10 kt. Seas around 2 ft. Wave
Detail: SE 2 ft at 8 seconds and N 1 foot at 3 seconds.
.MON THROUGH TUE NIGHT...E winds 5 to 10 kt. Seas 2 to 3 ft. Wave
Detail: E 3 ft at 8 seconds and N 1 foot 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.

$$

ANZ255-300000-
Coastal Waters extending out to 25 nm South of Marthas Vineyard
and Nantucket-
704 AM EDT Fri Aug 29 2025

.TODAY...SE winds 5 to 10 kt with gusts up to 20 kt. Seas 2 to
3 ft. Wave Detail: S 3 ft at 6 seconds. A slight chance of
showers this afternoon.
.TONIGHT...S winds around 10 kt, becoming W after midnight. Seas
around 2 ft. Wave Detail: S 2 ft at 6 seconds. A chance of
showers. Patchy fog after midnight. Vsby 1 to 3 NM.
.SAT...W winds around 10 kt. Seas 2 to 3 ft. Wave Detail: W 2 ft
at 4 seconds and S 2 ft at 6 seconds.
.SAT NIGHT...W winds around 10 kt. Gusts up to 20 kt in the
evening. Seas 2 to 3 ft. Wave Detail: W 2 ft at 5 seconds and SE
2 ft at 6 seconds.
.SUN AND SUN NIGHT...NE winds 5 to 10 kt. Seas around 2 ft. Wave
Detail: NW 2 ft at 3 seconds and SE 2 ft at 7 seconds.
.MON THROUGH TUE NIGHT...E winds 5 to 10 kt. Seas 2 to 3 ft. Wave
Detail: SE 3 ft at 8 seconds and NE 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.

$$

ANZ256-300000-
Coastal Waters from Montauk NY to Marthas Vineyard extending out
to 20 nm South of Block Island-
704 AM EDT Fri Aug 29 2025

.TODAY...S winds around 10 kt. Gusts up to 20 kt this morning.
Seas around 3 ft. Wave Detail: S 3 ft at 6 seconds. A slight
chance of showers. A chance of tstms this afternoon. Some tstms
may produce gusty winds, small hail, and heavy rainfall this
afternoon.
.TONIGHT...SW winds around 10 kt, becoming NW after midnight.
Gusts up to 20 kt. Seas 2 to 3 ft. Wave Detail: SW 2 ft at
5 seconds and SE 2 ft at 7 seconds. A chance of showers.
.SAT...NW winds around 10 kt, becoming W with gusts up to 20 kt
in the afternoon. Seas 2 to 3 ft. Wave Detail: NW 2 ft at
4 seconds and SE 2 ft at 7 seconds.
.SAT NIGHT...W winds around 10 kt with gusts up to 20 kt,
becoming NW after midnight. Seas 2 to 3 ft. Wave Detail: W 2 ft
at 4 seconds and SE 2 ft at 6 seconds.
.SUN...N winds around 10 kt, becoming W in the afternoon. Seas
around 2 ft. Wave Detail: N 2 ft at 3 seconds and SE 2 ft at
8 seconds.
.SUN NIGHT...SE winds around 5 kt, becoming NE after midnight.
Seas around 2 ft. Wave Detail: SE 2 ft at 8 seconds and SW 1 foot
at 3 seconds.
.MON THROUGH TUE NIGHT...E winds 5 to 10 kt. Seas 2 to 3 ft.

Winds and seas higher in and near tstms.

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.

$$

ANZ232-300000-
Nantucket Sound-
704 AM EDT Fri Aug 29 2025

.TODAY...S winds 10 to 15 kt. Gusts up to 20 kt this afternoon.
Seas 2 to 3 ft. Wave Detail: S 2 ft at 3 seconds and SE 2 ft at
7 seconds. A slight chance of showers this afternoon.
.TONIGHT...S winds around 10 kt, becoming W after midnight. Seas
around 2 ft. Wave Detail: SE 1 foot at 5 seconds. Showers likely,
mainly in the evening.
.SAT...W winds 5 to 10 kt. Seas around 2 ft. Wave Detail: W 2 ft
at 3 seconds and SE 1 foot at 6 seconds.
.SAT NIGHT...W winds around 10 kt with gusts up to 20 kt,
becoming NW after midnight. Seas around 2 ft. Wave Detail: W 2 ft
at 3 seconds and SE 1 foot at 6 seconds.
.SUN AND SUN NIGHT...N winds 5 to 10 kt. Seas around 2 ft. Wave
Detail: N 1 foot at 3 seconds and SE 1 foot at 7 seconds.
.MON THROUGH TUE NIGHT...E winds 5 to 10 kt. Seas around 2 ft.
Wave Detail: N 1 foot at 3 seconds and E 1 foot at 7 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.

$$

ANZ233-300000-
Vineyard Sound-
704 AM EDT Fri Aug 29 2025

.TODAY...S winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: S 2 ft
at 6 seconds and SE 1 foot at 3 seconds. A slight chance of
showers. Isolated tstms this afternoon. Some tstms may produce
gusty winds, small hail, and heavy rainfall this afternoon.
.TONIGHT...S winds 5 to 10 kt, becoming NW after midnight. Seas
around 2 ft. Wave Detail: S 2 ft at 6 seconds and E 1 foot at
3 seconds. Showers likely, mainly in the evening.
.SAT...NW winds 5 to 10 kt, becoming W with gusts up to 20 kt in
the afternoon. Seas around 2 ft. Wave Detail: W 2 ft at 4 seconds
and S 1 foot at 6 seconds.
.SAT NIGHT...W winds around 10 kt with gusts up to 20 kt,
becoming NW after midnight. Seas around 2 ft. Wave Detail: S 2 ft
at 5 seconds.
.SUN...N winds 5 to 10 kt, becoming SW in the afternoon. Seas
around 2 ft in the morning, then 1 foot or less. Wave Detail: NW
1 foot at 4 seconds and SE 1 foot at 7 seconds, becoming N 1 foot
at 3 seconds and W 1 foot at 3 seconds.
.SUN NIGHT...SE winds 5 to 10 kt, becoming NW after midnight.
Seas 1 foot or less. Wave Detail: NE 1 foot at 2 seconds and SW
1 foot at 3 seconds.
.MON THROUGH TUE NIGHT...SE winds 5 to 10 kt. Seas around 2 ft.

Winds and seas higher in and near tstms.

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.

$$

ANZ234-300000-
Buzzards Bay-
704 AM EDT Fri Aug 29 2025

.TODAY...S winds 5 to 10 kt. Gusts up to 20 kt this afternoon.
Seas 2 to 3 ft. Wave Detail: S 2 ft at 6 seconds. A slight chance
of showers. Isolated tstms this afternoon. Some tstms may produce
gusty winds, small hail, and heavy rainfall this afternoon.
.TONIGHT...SW winds 5 to 10 kt, becoming NW after midnight. Seas
around 2 ft. Wave Detail: SE 2 ft at 5 seconds. Showers likely,
mainly in the evening.
.SAT...NW winds 5 to 10 kt, becoming W with gusts up to 20 kt in
the afternoon. Seas around 2 ft. Wave Detail: NW 1 foot at
3 seconds and SE 1 foot at 6 seconds.
.SAT NIGHT...W winds around 10 kt with gusts up to 20 kt,
becoming NW after midnight. Seas around 2 ft in the evening, then
1 foot or less. Wave Detail: S 2 ft at 5 seconds, becoming W
1 foot at 4 seconds and SE 1 foot at 7 seconds.
.SUN...NW winds 5 to 10 kt, becoming S in the afternoon. Seas
1 foot or less. Wave Detail: N 1 foot at 3 seconds and SE 1 foot
at 7 seconds.
.SUN NIGHT...SE winds 5 to 10 kt, becoming NW after midnight.
Seas 1 foot or less. Wave Detail: NE 1 foot at 2 seconds and SW
1 foot at 3 seconds.
.MON THROUGH TUE NIGHT...SE winds 5 to 10 kt. Seas around 2 ft.

Winds and seas higher in and near tstms.

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.

$$

ANZ235-300000-
Rhode Island Sound-
704 AM EDT Fri Aug 29 2025

.TODAY...S winds around 10 kt. Gusts up to 20 kt this afternoon.
Seas 2 to 3 ft. Wave Detail: S 3 ft at 6 seconds. A slight chance
of showers this morning, then a chance of showers and tstms this
afternoon. Some tstms may produce gusty winds, small hail, and
heavy rainfall this afternoon.
.TONIGHT...SW winds around 10 kt, becoming NW with gusts up to
20 kt after midnight. Seas around 2 ft. Wave Detail: S 2 ft at
6 seconds. Showers likely with a chance of tstms in the evening,
then a chance of showers after midnight. Some tstms may produce
gusty winds, small hail, and heavy rainfall in the evening.
.SAT...NW winds 5 to 10 kt, becoming W with gusts up to 20 kt in
the afternoon. Seas 2 to 3 ft. Wave Detail: NW 2 ft at 3 seconds
and SE 2 ft at 6 seconds.
.SAT NIGHT...W winds around 10 kt with gusts up to 20 kt,
becoming NW after midnight. Seas around 2 ft. Wave Detail: SW
2 ft at 4 seconds and SE 2 ft at 6 seconds.
.SUN...N winds 5 to 10 kt, becoming SW in the afternoon. Seas
around 2 ft. Wave Detail: SE 2 ft at 7 seconds and N 1 foot at
3 seconds.
.SUN NIGHT...S winds 5 to 10 kt, becoming NW after midnight. Seas
around 2 ft. Wave Detail: SE 2 ft at 8 seconds and SW 1 foot at
3 seconds.
.MON THROUGH TUE NIGHT...SE winds 5 to 10 kt. Seas around 2 ft.

Winds and seas higher in and near tstms.

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.

$$

ANZ237-300000-
Block Island Sound-
704 AM EDT Fri Aug 29 2025

.TODAY...S winds around 10 kt with gusts up to 20 kt. Seas 2 to
3 ft. Wave Detail: SW 2 ft at 4 seconds and S 2 ft at 7 seconds.
A slight chance of showers this morning, then a chance of showers
and tstms this afternoon. Some tstms may produce gusty winds,
small hail, and heavy rainfall this afternoon.
.TONIGHT...W winds 5 to 10 kt, becoming NW after midnight. Gusts
up to 20 kt. Seas 2 to 3 ft. Wave Detail: NW 2 ft at 3 seconds
and SE 2 ft at 6 seconds. Showers likely with a chance of tstms
in the evening. Some tstms may produce gusty winds, small hail,
and heavy rainfall in the evening.
.SAT...NW winds 5 to 10 kt, becoming W with gusts up to 20 kt in
the afternoon. Seas around 2 ft. Wave Detail: NW 2 ft at
3 seconds and SE 2 ft at 7 seconds.
.SAT NIGHT...W winds 5 to 10 kt with gusts up to 20 kt, becoming
NW after midnight. Seas around 2 ft. Wave Detail: W 2 ft at
3 seconds and SE 2 ft at 6 seconds.
.SUN...N winds 5 to 10 kt, becoming SW in the afternoon. Seas
around 2 ft. Wave Detail: SE 2 ft at 7 seconds and NW 1 foot at
3 seconds.
.SUN NIGHT...S winds 5 to 10 kt, becoming NW after midnight. Seas
around 2 ft. Wave Detail: SE 2 ft at 8 seconds and SW 1 foot at
2 seconds.
.MON THROUGH TUE NIGHT...SE winds 5 to 10 kt. Seas around 2 ft.

Winds and seas higher in and near tstms.

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.

$$

ANZ230-300000-
Boston Harbor-
704 AM EDT Fri Aug 29 2025

.TODAY...S winds 5 to 10 kt with gusts up to 20 kt. Waves around
2 ft. A chance of showers this morning, then showers with a
chance of tstms this afternoon. Some tstms may produce gusty
winds, small hail, and heavy rainfall this afternoon.
.TONIGHT...SW winds 5 to 10 kt, becoming NW after midnight. Waves
1 foot or less, then around 2 ft after midnight. Showers in the
evening.
.SAT...W winds 5 to 10 kt. Waves around 2 ft in the morning, then
1 foot or less.
.SAT NIGHT...W winds 5 to 10 kt. Waves 1 foot or less.
.SUN...NW winds 5 to 10 kt, becoming E in the afternoon. Waves
1 foot or less.
.SUN NIGHT...SE winds 5 to 10 kt, becoming W after midnight.
Waves 1 foot or less.
.MON THROUGH TUE NIGHT...S winds 5 to 10 kt. Waves 1 foot or
less.

Winds and waves higher in and near tstms.

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.

$$

ANZ236-300000-
Narragansett Bay-
704 AM EDT Fri Aug 29 2025

.TODAY...S winds 5 to 10 kt. Gusts up to 20 kt this afternoon.
Waves around 2 ft. A slight chance of showers this morning, then
a chance of showers and tstms this afternoon. Some tstms may
produce gusty winds, small hail, and heavy rainfall this
afternoon.
.TONIGHT...SW winds 5 to 10 kt, becoming NW with gusts up to
20 kt after midnight. Waves around 2 ft. Showers with a chance of
tstms in the evening. Some tstms may produce gusty winds, small
hail, and heavy rainfall in the evening.
.SAT...NW winds 5 to 10 kt. Waves around 2 ft.
.SAT NIGHT...NW winds 5 to 10 kt. Waves around 2 ft.
.SUN...N winds 5 to 10 kt, becoming W in the afternoon. Waves
1 foot or less.
.SUN NIGHT...S winds 5 to 10 kt, becoming NW after midnight.
Waves 1 foot or less.
.MON THROUGH TUE NIGHT...S winds 5 to 10 kt. Waves around 2 ft.

Winds and waves higher in and near tstms.

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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