500
FZUS51 KBOX 302305
CWFBOX

Coastal Waters Forecast for Massachusetts and Rhode Island
National Weather Service Boston/Norton MA
705 PM EDT Sat Aug 30 2025

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

ANZ200-311200-
705 PM EDT Sat Aug 30 2025

.Synopsis for Massachusetts and Rhode Island coastal waters...
High pressure 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.

$$

ANZ250-311200-
Coastal waters east of Ipswich Bay and the Stellwagen Bank
National Marine Sanctuary-
705 PM EDT Sat Aug 30 2025

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

$$

ANZ251-311200-
Massachusetts Bay and Ipswich Bay-
705 PM EDT Sat Aug 30 2025

.TONIGHT...SW winds 5 to 10 kt, becoming NW after midnight. Seas
around 2 ft. Wave Detail: E 2 ft at 8 seconds and W 1 foot at
2 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 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 7 seconds and N 1 foot at 3 seconds.
.MON NIGHT AND TUE...E winds 5 to 10 kt. Seas around 2 ft. Wave
Detail: E 2 ft at 8 seconds and NE 1 foot at 3 seconds.
.TUE NIGHT...SE winds around 10 kt, becoming SW after midnight.
Seas 2 to 3 ft. Wave Detail: E 3 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 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.

$$

ANZ231-311200-
Cape Cod Bay-
705 PM EDT Sat Aug 30 2025

.TONIGHT...SW winds 5 to 10 kt, becoming NW after midnight. Seas
around 2 ft. Wave Detail: SE 2 ft at 8 seconds and S 1 foot at
3 seconds.
.SUN...NW winds around 10 kt, becoming N in the afternoon. Seas
around 2 ft. Wave Detail: SE 2 ft at 7 seconds and N 1 foot at
3 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 S
1 foot at 5 seconds.
.MON...NE winds 5 to 10 kt. Seas 1 foot or less. Wave Detail: N
1 foot at 3 seconds and SE 1 foot at 6 seconds.
.MON NIGHT AND TUE...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.
.TUE NIGHT...E winds 5 to 10 kt, becoming SW after midnight. Seas
around 2 ft. Wave Detail: E 2 ft at 8 seconds and SW 1 foot at
2 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
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.

$$

ANZ254-311200-
Coastal waters from Provincetown MA to Chatham MA to Nantucket MA
out 20 nm-
705 PM EDT Sat Aug 30 2025

.TONIGHT...SW winds 5 to 10 kt, becoming W after midnight. Seas
2 to 3 ft. Wave Detail: SE 3 ft at 8 seconds and SW 1 foot at
4 seconds.
.SUN...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.
.SUN NIGHT...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 AND TUE...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 1 foot at
3 seconds.
.TUE NIGHT...NE winds 5 to 10 kt, becoming W after midnight. Seas
2 to 4 ft. Wave Detail: E 4 ft at 9 seconds.
.WED THROUGH THU...S winds 10 to 15 kt with gusts up to 20 kt.
Seas 3 to 4 ft.
.THU NIGHT...SE 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.

$$

ANZ255-311200-
Coastal Waters extending out to 25 nm South of Marthas Vineyard
and Nantucket-
705 PM EDT Sat Aug 30 2025

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

$$

ANZ256-311200-
Coastal Waters from Montauk NY to Marthas Vineyard extending out
to 20 nm South of Block Island-
705 PM EDT Sat Aug 30 2025

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

$$

ANZ232-311200-
Nantucket Sound-
705 PM EDT Sat Aug 30 2025

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

$$

ANZ233-311200-
Vineyard Sound-
705 PM EDT Sat Aug 30 2025

.TONIGHT...W winds around 10 kt, becoming NW after midnight. Seas
around 2 ft. Wave Detail: SW 1 foot at 5 seconds.
.SUN...N winds 5 to 10 kt, becoming SE in the afternoon. Seas
around 2 ft. Wave Detail: N 1 foot at 3 seconds and S 1 foot at
6 seconds.
.SUN NIGHT...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 5 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 6 seconds.
.MON NIGHT AND TUE...NE winds 10 to 15 kt. Seas around 2 ft. Wave
Detail: SE 2 ft at 8 seconds and E 1 foot at 4 seconds.
.TUE NIGHT...E winds 5 to 10 kt, becoming SW after midnight. Seas
around 2 ft. Wave Detail: SE 2 ft at 8 seconds and SW 1 foot at
2 seconds.
.WED THROUGH THU...S winds 10 to 15 kt with gusts up to 20 kt.
Seas 2 to 3 ft.
.THU NIGHT...SE 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.

$$

ANZ234-311200-
Buzzards Bay-
705 PM EDT Sat Aug 30 2025

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

$$

ANZ235-311200-
Rhode Island Sound-
705 PM EDT Sat Aug 30 2025

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

$$

ANZ237-311200-
Block Island Sound-
705 PM EDT Sat Aug 30 2025

.TONIGHT...W winds around 10 kt, becoming NW after midnight. Seas
2 to 3 ft. Wave Detail: SE 2 ft at 7 seconds and SW 1 foot at
4 seconds.
.SUN...N winds 5 to 10 kt, becoming S in the afternoon. Seas 2 to
3 ft. Wave Detail: SE 2 ft at 7 seconds and N 1 foot at
2 seconds.
.SUN NIGHT...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
4 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 AND TUE...E winds around 10 kt. Seas around 2 ft. Wave
Detail: E 2 ft at 3 seconds and SE 2 ft at 8 seconds.
.TUE NIGHT...SE winds 5 to 10 kt, becoming W after midnight. Seas
2 to 3 ft. Wave Detail: SE 3 ft at 8 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 3 ft.
.THU NIGHT...SE 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.

$$

ANZ230-311200-
Boston Harbor-
705 PM EDT Sat Aug 30 2025

.TONIGHT...NW 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...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 AND TUE...E winds 5 to 10 kt. Waves around 2 ft.
.TUE NIGHT...SE winds 5 to 10 kt, becoming SW after midnight.
Waves 1 foot or less.
.WED THROUGH THU...S winds 10 to 15 kt with gusts up to 20 kt.
Waves 2 to 3 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.

$$

ANZ236-311200-
Narragansett Bay-
705 PM EDT Sat Aug 30 2025

.TONIGHT...W winds 5 to 10 kt, becoming NW after midnight. Waves
around 2 ft.
.SUN...N winds 5 to 10 kt, becoming SE in the afternoon. Waves
around 2 ft.
.SUN NIGHT...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 in the
evening, then 1 foot or less.
.TUE AND TUE NIGHT...W winds 5 to 10 kt. 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...SE winds 10 to 15 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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