315
FZUS51 KBOX 301706
CWFBOX

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

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

ANZ200-310600-
106 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.

$$

ANZ250-310600-
Coastal waters east of Ipswich Bay and the Stellwagen Bank
National Marine Sanctuary-
106 PM EDT Sat Aug 30 2025

.THIS AFTERNOON...SW winds 5 to 10 kt. Seas around 2 ft. Wave
Detail: SE 2 ft at 8 seconds and W 1 foot at 3 seconds.
.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...N winds 5 to 10 kt, becoming E 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 AND MON NIGHT...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.
.TUE THROUGH WED NIGHT...S winds 10 to 15 kt with gusts up to
20 kt. Seas 2 to 4 ft. Wave Detail: SE 4 ft at 8 seconds and S
2 ft at 4 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.

$$

ANZ251-310600-
Massachusetts Bay and Ipswich Bay-
106 PM EDT Sat Aug 30 2025

.THIS AFTERNOON...S winds 5 to 10 kt. Seas around 2 ft. Wave
Detail: NW 1 foot at 3 seconds and SE 1 foot at 4 seconds.
.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...N 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 AND MON NIGHT...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.
.TUE...NE winds 5 to 10 kt. Seas around 2 ft. Wave Detail: E 2 ft
at 8 seconds and NE 1 foot at 4 seconds.
.TUE NIGHT THROUGH WED NIGHT...S 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.

$$

ANZ231-310600-
Cape Cod Bay-
106 PM EDT Sat Aug 30 2025

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

$$

ANZ254-310600-
Coastal waters from Provincetown MA to Chatham MA to Nantucket MA
out 20 nm-
106 PM EDT Sat Aug 30 2025

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

$$

ANZ255-310600-
Coastal Waters extending out to 25 nm South of Marthas Vineyard
and Nantucket-
106 PM EDT Sat Aug 30 2025

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

$$

ANZ256-310600-
Coastal Waters from Montauk NY to Marthas Vineyard extending out
to 20 nm South of Block Island-
106 PM EDT Sat Aug 30 2025

.THIS AFTERNOON...W winds around 10 kt. Seas 2 to 3 ft. Wave
Detail: W 2 ft at 3 seconds and SE 2 ft at 7 seconds.
.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
3 seconds.
.SUN...N winds 5 to 10 kt, becoming SE 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: S 2 ft at 6 seconds.
.MON AND MON NIGHT...NE winds around 10 kt. Seas 2 to 3 ft. Wave
Detail: E 3 ft at 8 seconds and NE 2 ft at 3 seconds.
.TUE THROUGH WED NIGHT...S winds 10 to 15 kt. Seas 2 to 4 ft.
Wave Detail: SE 4 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.

$$

ANZ232-310600-
Nantucket Sound-
106 PM EDT Sat Aug 30 2025

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

$$

ANZ233-310600-
Vineyard Sound-
106 PM EDT Sat Aug 30 2025

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

$$

ANZ234-310600-
Buzzards Bay-
106 PM EDT Sat Aug 30 2025

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

$$

ANZ235-310600-
Rhode Island Sound-
106 PM EDT Sat Aug 30 2025

.THIS AFTERNOON...SW winds around 10 kt. Seas 2 to 3 ft. Wave
Detail: W 2 ft at 3 seconds and S 2 ft at 7 seconds.
.TONIGHT...W winds around 10 kt, becoming NW after midnight. Seas
2 to 3 ft. Wave Detail: SW 2 ft at 3 seconds and S 2 ft at
7 seconds.
.SUN...N winds 5 to 10 kt, becoming S 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 5 to 10 kt, becoming NE after midnight.
Seas around 2 ft. Wave Detail: SE 2 ft at 8 seconds and SW 1 foot
at 5 seconds.
.MON AND MON NIGHT...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.
.TUE THROUGH WED NIGHT...S 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 4 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.

$$

ANZ237-310600-
Block Island Sound-
106 PM EDT Sat Aug 30 2025

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

$$

ANZ230-310600-
Boston Harbor-
106 PM EDT Sat Aug 30 2025

.THIS AFTERNOON...SW winds around 10 kt. Waves 1 foot or less.
.TONIGHT...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...S winds 5 to 10 kt, becoming W after midnight. Waves
1 foot or less.
.MON AND MON NIGHT...N winds 5 to 10 kt. Waves around 2 ft.
.TUE THROUGH WED NIGHT...S 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.

$$

ANZ236-310600-
Narragansett Bay-
106 PM EDT Sat Aug 30 2025

.THIS AFTERNOON...W winds around 10 kt. Waves around 2 ft.
.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 in the morning, then 1 foot or less.
.SUN NIGHT...S winds 5 to 10 kt, becoming N after midnight. Waves
1 foot or less.
.MON...NE winds 5 to 10 kt. 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, then
around 2 ft after midnight.
.TUE THROUGH WED NIGHT...S 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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