499
FZUS51 KBOX 311105
CWFBOX

Coastal Waters Forecast for Massachusetts and Rhode Island
National Weather Service Boston/Norton MA
704 AM EDT Sun Aug 31 2025

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

ANZ200-010000-
704 AM EDT Sun Aug 31 2025

.Synopsis for Massachusetts and Rhode Island coastal waters...
High pres will build into the Northeast through this weekend, and
remain anchored over the region into the middle of next week. Expect
dry conditions and winds less than 25 kts.

$$

ANZ250-010000-
Coastal waters east of Ipswich Bay and the Stellwagen Bank
National Marine Sanctuary-
704 AM EDT Sun Aug 31 2025

.TODAY...NW winds 5 to 10 kt, becoming NE this afternoon. Seas
2 to 3 ft. Wave Detail: NW 2 ft at 3 seconds and SE 2 ft at
8 seconds.
.TONIGHT...S winds around 5 kt, becoming NW after midnight. Seas
around 2 ft. Wave Detail: SE 2 ft at 8 seconds and N 1 foot at
3 seconds.
.MON...NE winds 5 to 10 kt. Seas around 2 ft. Wave Detail: SE
2 ft at 7 seconds and N 1 foot at 3 seconds.
.MON NIGHT...NE winds 5 to 10 kt. Seas around 2 ft. Wave Detail:
SE 2 ft at 9 seconds and N 1 foot at 3 seconds.
.TUE...NE winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to
4 ft. Wave Detail: E 4 ft at 9 seconds and NE 2 ft at 4 seconds.
.TUE NIGHT...E winds around 10 kt, becoming W after midnight.
Seas 3 to 5 ft. Wave Detail: E 5 ft at 9 seconds and NE 1 foot at
3 seconds.
.WED...SW winds 10 to 15 kt with gusts up to 20 kt. Seas 3 to
5 ft.
.WED NIGHT THROUGH THU NIGHT...S winds 10 to 15 kt with gusts up
to 25 kt. Seas 2 to 4 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.

$$

ANZ251-010000-
Massachusetts Bay and Ipswich Bay-
704 AM EDT Sun Aug 31 2025

.TODAY...N winds 5 to 10 kt, becoming E this afternoon. Seas
around 2 ft. Wave Detail: E 2 ft at 8 seconds and N 1 foot at
3 seconds.
.TONIGHT...S winds 5 to 10 kt, becoming NW after midnight. Seas
around 2 ft. Wave Detail: E 2 ft at 8 seconds and SE 1 foot at
2 seconds.
.MON...NE winds 5 to 10 kt. Seas around 2 ft. Wave Detail: E 2 ft
at 8 seconds and N 1 foot at 3 seconds.
.MON NIGHT...NE winds 5 to 10 kt. Seas around 2 ft in the
evening, then 1 foot or less. Wave Detail: NE 1 foot at 3 seconds
and E 1 foot at 7 seconds.
.TUE...NE winds around 10 kt. Seas around 2 ft. Wave Detail: NE
2 ft at 4 seconds and E 2 ft at 8 seconds.
.TUE NIGHT...SE winds around 10 kt, becoming SW after midnight.
Seas 2 to 4 ft. Wave Detail: E 4 ft at 9 seconds and NE 2 ft at
4 seconds.
.WED THROUGH THU NIGHT...S winds 10 to 15 kt with gusts up to
25 kt. Seas 2 to 4 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.

$$

ANZ231-010000-
Cape Cod Bay-
704 AM EDT Sun Aug 31 2025

.TODAY...N winds 5 to 10 kt, becoming NE this afternoon. Seas
around 2 ft. Wave Detail: SE 2 ft at 8 seconds and N 1 foot at
3 seconds.
.TONIGHT...SE winds around 5 kt, becoming NW after midnight. Seas
1 foot or less. Wave Detail: N 1 foot at 3 seconds and SE 1 foot
at 8 seconds.
.MON...NE winds 5 to 10 kt. Seas 1 foot or less. Wave Detail: N
1 foot at 3 seconds and E 1 foot at 7 seconds.
.MON NIGHT...NE winds 5 to 10 kt. Seas 1 foot or less, then
around 2 ft after midnight. Wave Detail: NE 1 foot at 3 seconds
and E 1 foot at 7 seconds.
.TUE...NE winds 10 to 15 kt with gusts up to 20 kt. Seas around
2 ft. Wave Detail: N 2 ft at 3 seconds and E 2 ft at 8 seconds.
.TUE NIGHT...N winds 5 to 10 kt, becoming W after midnight. Seas
around 2 ft. Wave Detail: E 2 ft at 9 seconds and N 1 foot at
3 seconds.
.WED THROUGH THU NIGHT...S 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.

$$

ANZ254-010000-
Coastal waters from Provincetown MA to Chatham MA to Nantucket MA
out 20 nm-
704 AM EDT Sun Aug 31 2025

.TODAY...N winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: SE 3 ft
at 7 seconds and NW 1 foot at 3 seconds.
.TONIGHT...NE winds around 5 kt. Seas 2 to 3 ft. Wave Detail: SE
2 ft at 8 seconds and N 1 foot at 4 seconds.
.MON...NE winds 5 to 10 kt. Seas around 2 ft. Wave Detail: SE
2 ft at 7 seconds and N 1 foot at 4 seconds.
.MON NIGHT...NE winds 5 to 10 kt, increasing to 10 to 15 kt with
gusts up to 20 kt after midnight. Seas 2 to 3 ft. Wave Detail: NE
2 ft at 4 seconds and SE 2 ft at 8 seconds.
.TUE...NE winds 10 to 15 kt with gusts up to 20 kt. Seas 3 to
5 ft. Wave Detail: E 5 ft at 9 seconds and NE 3 ft at 5 seconds.
.TUE NIGHT...N winds 10 to 15 kt with gusts up to 20 kt, becoming
NW after midnight. Seas 3 to 5 ft. Wave Detail: E 5 ft at
9 seconds and NE 1 foot at 3 seconds.
.WED...SW winds 10 to 15 kt with gusts up to 20 kt. Seas 3 to
5 ft.
.WED NIGHT THROUGH THU NIGHT...SE winds 10 to 15 kt with gusts up
to 20 kt. Seas 2 to 4 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.

$$

ANZ255-010000-
Coastal Waters extending out to 25 nm South of Marthas Vineyard
and Nantucket-
704 AM EDT Sun Aug 31 2025

.TODAY...N winds 5 to 10 kt, becoming NE this afternoon. Seas
2 to 3 ft. Wave Detail: NW 2 ft at 4 seconds and SE 2 ft at
7 seconds.
.TONIGHT...NE winds 5 to 10 kt. Seas around 2 ft. Wave Detail: SE
2 ft at 7 seconds and NE 1 foot at 3 seconds.
.MON...NE winds around 10 kt. Seas 2 to 3 ft. Wave Detail: NE
2 ft at 3 seconds and SE 2 ft at 7 seconds.
.MON NIGHT...NE winds 10 to 15 kt with gusts up to 20 kt. Seas
2 to 3 ft. Wave Detail: E 3 ft at 8 seconds and NE 2 ft at
3 seconds.
.TUE...NE winds 15 to 20 kt. Seas 3 to 5 ft. Wave Detail: E 5 ft
at 8 seconds and NE 2 ft at 4 seconds.
.TUE NIGHT...NE winds 10 to 15 kt with gusts up to 20 kt,
becoming NW after midnight. Seas 3 to 5 ft. Wave Detail: E 5 ft
at 9 seconds and N 1 foot at 4 seconds.
.WED...SW winds 10 to 15 kt. Seas 3 to 5 ft.
.WED NIGHT THROUGH THU NIGHT...SE winds 10 to 15 kt with gusts up
to 20 kt. Seas 2 to 4 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.

$$

ANZ256-010000-
Coastal Waters from Montauk NY to Marthas Vineyard extending out
to 20 nm South of Block Island-
704 AM EDT Sun Aug 31 2025

.TODAY...N winds 5 to 10 kt, becoming SE this afternoon. Seas
2 to 3 ft. Wave Detail: N 2 ft at 3 seconds and SE 2 ft at
7 seconds.
.TONIGHT...SE winds around 5 kt, becoming NE after midnight. Seas
around 2 ft. Wave Detail: SE 2 ft at 8 seconds and NE 1 foot at
2 seconds.
.MON...NE winds 10 to 15 kt. Seas 2 to 3 ft. Wave Detail: SE 3 ft
at 7 seconds and NE 2 ft at 3 seconds.
.MON NIGHT...NE winds 10 to 15 kt with gusts up to 20 kt. Seas
2 to 3 ft. Wave Detail: E 3 ft at 7 seconds and E 2 ft at
4 seconds.
.TUE...NE winds 10 to 15 kt with gusts up to 20 kt. Seas 3 to
4 ft. Wave Detail: E 4 ft at 9 seconds and NE 2 ft at 4 seconds.
.TUE NIGHT...E winds 10 to 15 kt, becoming W after midnight. Seas
4 to 5 ft. Wave Detail: E 5 ft at 9 seconds and NE 1 foot at
3 seconds.
.WED THROUGH THU...S winds 10 to 15 kt with gusts up to 20 kt.
Seas 2 to 4 ft.
.THU NIGHT...S winds 10 to 15 kt with gusts up to 20 kt. Seas
around 3 ft. A chance of showers.

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.

$$

ANZ232-010000-
Nantucket Sound-
704 AM EDT Sun Aug 31 2025

.TODAY...N winds around 10 kt, becoming NE this afternoon. Seas
around 2 ft. Wave Detail: N 1 foot at 3 seconds and S 1 foot at
6 seconds.
.TONIGHT...E winds 5 to 10 kt, becoming NE after midnight. Seas
around 2 ft in the evening, then 1 foot or less. Wave Detail: N
1 foot at 3 seconds and E 1 foot at 8 seconds, becoming N 1 foot
at 3 seconds and E 1 foot at 7 seconds.
.MON...NE winds 5 to 10 kt. Seas around 2 ft. Wave Detail: N
1 foot at 3 seconds and E 1 foot at 7 seconds.
.MON NIGHT...NE winds 10 to 15 kt. Seas around 2 ft. Wave Detail:
NE 2 ft at 3 seconds and E 1 foot at 7 seconds.
.TUE...NE winds around 15 kt with gusts up to 20 kt. Seas 2 to
3 ft. Wave Detail: NE 2 ft at 4 seconds and E 2 ft at 8 seconds.
.TUE NIGHT...NE winds 10 to 15 kt with gusts up to 20 kt,
becoming W after midnight. Seas 2 to 3 ft. Wave Detail: E 3 ft at
9 seconds and NE 2 ft at 4 seconds.
.WED THROUGH THU NIGHT...S 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.

$$

ANZ233-010000-
Vineyard Sound-
704 AM EDT Sun Aug 31 2025

.TODAY...N winds 5 to 10 kt, becoming SE this afternoon. Seas
around 2 ft. Wave Detail: N 1 foot at 3 seconds and S 1 foot at
6 seconds.
.TONIGHT...SE winds around 5 kt, becoming N after midnight. Seas
1 foot or less. Wave Detail: NE 1 foot at 2 seconds and SW 1 foot
at 4 seconds.
.MON...NE winds 5 to 10 kt. Seas around 2 ft. Wave Detail: NE
1 foot at 2 seconds and SE 1 foot at 7 seconds.
.MON NIGHT...NE winds 10 to 15 kt. Seas around 2 ft. Wave Detail:
NE 1 foot at 3 seconds and SE 1 foot at 8 seconds.
.TUE...NE winds 10 to 15 kt with gusts up to 20 kt. Seas around
2 ft. Wave Detail: SE 2 ft at 8 seconds and NE 1 foot at
3 seconds.
.TUE NIGHT...NE winds 10 to 15 kt, becoming W after midnight.
Seas around 2 ft. Wave Detail: SE 2 ft at 9 seconds and W 1 foot
at 2 seconds.
.WED THROUGH THU...S winds 10 to 15 kt with gusts up to 20 kt.
Seas around 2 ft.
.THU NIGHT...S winds 10 to 15 kt. Seas around 2 ft. A chance of
showers.

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.

$$

ANZ234-010000-
Buzzards Bay-
704 AM EDT Sun Aug 31 2025

.TODAY...N winds 5 to 10 kt, becoming SE this afternoon. Seas
around 2 ft this morning, then 1 foot or less. Wave Detail: N
1 foot at 3 seconds and S 1 foot at 5 seconds, becoming N 1 foot
at 2 seconds and W 1 foot at 3 seconds.
.TONIGHT...S winds around 5 kt, becoming NW after midnight. Seas
1 foot or less. Wave Detail: NE 1 foot at 2 seconds and NW 1 foot
at 3 seconds.
.MON...NE winds 5 to 10 kt. Seas 1 foot or less, then around 2 ft
in the afternoon. Wave Detail: N 1 foot at 2 seconds and SE
1 foot at 7 seconds, becoming E 1 foot at 3 seconds and SE 1 foot
at 7 seconds.
.MON NIGHT...NE winds 10 to 15 kt. Seas 1 foot or less, then
around 2 ft after midnight. Wave Detail: NE 1 foot at 2 seconds
and SE 1 foot at 7 seconds.
.TUE...NE winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to
3 ft. Wave Detail: SE 2 ft at 8 seconds and NE 1 foot at
3 seconds.
.TUE NIGHT...NE winds 10 to 15 kt, becoming W after midnight.
Seas around 2 ft. Wave Detail: SE 2 ft at 9 seconds and W 1 foot
at 2 seconds.
.WED THROUGH THU NIGHT...S 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.

$$

ANZ235-010000-
Rhode Island Sound-
704 AM EDT Sun Aug 31 2025

.TODAY...N winds 5 to 10 kt, becoming S this afternoon. Seas 2 to
3 ft. Wave Detail: SE 2 ft at 7 seconds and N 1 foot at
3 seconds.
.TONIGHT...SE winds 5 to 10 kt, becoming N after midnight. Seas
around 2 ft. Wave Detail: SE 2 ft at 8 seconds and NE 1 foot at
2 seconds.
.MON...NE winds 5 to 10 kt. Seas around 2 ft. Wave Detail: E 2 ft
at 3 seconds and SE 2 ft at 7 seconds.
.MON NIGHT...NE winds 10 to 15 kt. Seas around 2 ft. Wave Detail:
E 2 ft at 3 seconds and SE 2 ft at 7 seconds.
.TUE...NE winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to
3 ft. Wave Detail: SE 3 ft at 9 seconds and NE 2 ft at 3 seconds.
.TUE NIGHT...E winds 10 to 15 kt, becoming SW after midnight.
Seas 2 to 4 ft. Wave Detail: SE 4 ft at 9 seconds and NE 2 ft at
3 seconds.
.WED THROUGH THU...S winds 10 to 15 kt with gusts up to 20 kt.
Seas 2 to 3 ft.
.THU NIGHT...S winds 10 to 15 kt with gusts up to 20 kt. Seas
2 to 3 ft. A chance of showers.

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.

$$

ANZ237-010000-
Block Island Sound-
704 AM EDT Sun Aug 31 2025

.TODAY...N winds 5 to 10 kt, becoming S this afternoon. Seas 2 to
3 ft. Wave Detail: SE 2 ft at 7 seconds and N 1 foot at
2 seconds.
.TONIGHT...S winds 5 to 10 kt, becoming NE after midnight. Seas
around 2 ft. Wave Detail: SE 2 ft at 8 seconds and S 1 foot at
3 seconds.
.MON...NE winds 5 to 10 kt, becoming E in the afternoon. Seas
around 2 ft. Wave Detail: E 2 ft at 3 seconds and SE 2 ft at
7 seconds.
.MON NIGHT...NE winds 10 to 15 kt. Seas around 2 ft. Wave Detail:
E 2 ft at 3 seconds and SE 2 ft at 7 seconds.
.TUE...NE winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to
3 ft. Wave Detail: SE 3 ft at 9 seconds and NE 2 ft at 3 seconds.
.TUE NIGHT...SE winds around 10 kt, becoming SW after midnight.
Seas 2 to 4 ft. Wave Detail: SE 4 ft at 9 seconds and NE 1 foot
at 4 seconds.
.WED THROUGH THU...S winds 10 to 15 kt with gusts up to 20 kt.
Seas 2 to 4 ft.
.THU NIGHT...S winds 10 to 15 kt with gusts up to 20 kt. Seas
2 to 3 ft. A chance of showers.

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.

$$

ANZ230-010000-
Boston Harbor-
704 AM EDT Sun Aug 31 2025

.TODAY...N winds 5 to 10 kt, becoming E this afternoon. Waves
1 foot or less.
.TONIGHT...SE winds 5 to 10 kt, becoming NW after midnight. Waves
1 foot or less.
.MON...N winds 5 to 10 kt, becoming NE in the afternoon. Waves
1 foot or less, then around 2 ft in the afternoon.
.MON NIGHT...NE winds 5 to 10 kt. Waves 1 foot or less.
.TUE...NE winds 5 to 10 kt. Waves 1 foot or less, then around
2 ft in the afternoon.
.TUE NIGHT...SE winds 5 to 10 kt, becoming SW after midnight.
Waves around 2 ft in the evening, then 1 foot or less.
.WED THROUGH THU...S winds 10 to 15 kt with gusts up to 20 kt.
Waves around 2 ft.
.THU NIGHT...S winds 10 to 15 kt with gusts up to 20 kt. Waves
around 2 ft. A chance of showers.

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.

$$

ANZ236-010000-
Narragansett Bay-
704 AM EDT Sun Aug 31 2025

.TODAY...N winds 5 to 10 kt, becoming S this afternoon. Waves
around 2 ft.
.TONIGHT...S winds 5 to 10 kt, becoming NW after midnight. Waves
1 foot or less.
.MON...NE winds 5 to 10 kt, becoming E in the afternoon. Waves
1 foot or less, then around 2 ft in the afternoon.
.MON NIGHT...NE winds 5 to 10 kt. Waves around 2 ft.
.TUE...NE winds around 10 kt. Waves around 2 ft.
.TUE NIGHT...SE winds 5 to 10 kt, becoming SW after midnight.
Waves around 2 ft.
.WED THROUGH THU...S winds 10 to 15 kt with gusts up to 20 kt.
Waves around 2 ft.
.THU NIGHT...S winds 10 to 15 kt with gusts up to 20 kt. Waves
around 2 ft. A chance of showers.

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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