847
FZUS51 KBOX 300506
CWFBOX

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

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

ANZ200-301800-
105 AM EDT Sat Aug 30 2025

.Synopsis for Massachusetts and Rhode Island coastal waters...
A cold front will move offshore tonight. High pressure will build
into the Northeast behind the front and remain anchored over the
region into the middle of next week.

$$

ANZ250-301800-
Coastal waters east of Ipswich Bay and the Stellwagen Bank
National Marine Sanctuary-
105 AM EDT Sat Aug 30 2025

.REST OF TONIGHT...W winds around 10 kt. Seas around 2 ft. Wave
Detail: SE 2 ft at 5 seconds and W 1 foot at 3 seconds. A chance
of showers with a slight chance of tstms.
.SAT...NW winds around 10 kt, becoming W in the afternoon. Seas
around 2 ft. Wave Detail: NW 2 ft at 3 seconds and SE 2 ft at
8 seconds.
.SAT NIGHT...SW winds around 10 kt, becoming NW after midnight.
Seas 2 to 3 ft. Wave Detail: NW 2 ft at 3 seconds and SE 2 ft at
7 seconds.
.SUN...NW winds 5 to 10 kt, becoming NE in the afternoon. Seas
2 to 3 ft. Wave Detail: NW 2 ft at 3 seconds and SE 2 ft at
8 seconds.
.SUN NIGHT...S winds around 5 kt, becoming W after midnight. Seas
around 2 ft. Wave Detail: SE 2 ft at 8 seconds and NW 1 foot at
3 seconds.
.MON AND MON 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.
.TUE AND TUE NIGHT...NE winds 5 to 10 kt, becoming S. Seas around
2 ft.
.WED AND WED NIGHT...S winds 10 to 15 kt with gusts up to 20 kt.
Seas 2 to 4 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.

$$

ANZ251-301800-
Massachusetts Bay and Ipswich Bay-
105 AM EDT Sat Aug 30 2025

.REST OF TONIGHT...W winds around 10 kt. Seas around 2 ft. Wave
Detail: SE 2 ft at 4 seconds and W 1 foot at 2 seconds. A slight
chance of showers with isolated tstms.
.SAT...NW winds around 10 kt, becoming SW in the afternoon. Seas
around 2 ft. Wave Detail: N 1 foot at 3 seconds and SE 1 foot at
4 seconds.
.SAT NIGHT...SW winds 5 to 10 kt, becoming NW after midnight.
Seas around 2 ft. Wave Detail: E 2 ft at 8 seconds and NE 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 W after midnight. Seas
around 2 ft. Wave Detail: E 2 ft at 8 seconds and SE 1 foot at
3 seconds.
.MON AND MON NIGHT...NW winds 5 to 10 kt. Seas around 2 ft. Wave
Detail: E 2 ft at 7 seconds and N 1 foot at 2 seconds.
.TUE THROUGH WED NIGHT...S winds 10 to 15 kt with gusts up to
20 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.

$$

ANZ231-301800-
Cape Cod Bay-
105 AM EDT Sat Aug 30 2025

.REST OF TONIGHT...W winds 5 to 10 kt. Seas 1 foot or less. Wave
Detail: W 1 foot at 2 seconds and SE 1 foot at 4 seconds. A
chance of showers with isolated tstms.
.SAT...NW winds around 10 kt, becoming N in the afternoon. Seas
around 2 ft in the morning, then 1 foot or less. Wave Detail: NW
1 foot at 3 seconds and SE 1 foot at 5 seconds, becoming N 1 foot
at 3 seconds and SE 1 foot at 6 seconds.
.SAT NIGHT...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 6 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 S 1 foot
at 7 seconds.
.SUN NIGHT...SE winds around 5 kt, becoming W 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 7 seconds.
.TUE THROUGH WED 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.

$$

ANZ254-301800-
Coastal waters from Provincetown MA to Chatham MA to Nantucket MA
out 20 nm-
105 AM EDT Sat Aug 30 2025

.REST OF TONIGHT...SW winds around 10 kt. Seas around 2 ft. Wave
Detail: S 2 ft at 4 seconds and E 1 foot at 8 seconds. A chance
of showers with isolated tstms.
.SAT...W winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: SE 3 ft
at 8 seconds and W 1 foot at 3 seconds.
.SAT NIGHT...SW winds 5 to 10 kt, becoming NW after midnight.
Seas 2 to 3 ft. Wave Detail: S 2 ft at 7 seconds and SE 2 ft at
8 seconds.
.SUN...N 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.
.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 8 seconds and N 1 foot at 3 seconds.
.TUE THROUGH WED NIGHT...S winds 5 to 10 kt. Seas 2 to 4 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.

$$

ANZ255-301800-
Coastal Waters extending out to 25 nm South of Marthas Vineyard
and Nantucket-
105 AM EDT Sat Aug 30 2025

.REST OF TONIGHT...W winds around 10 kt. Seas around 2 ft. Wave
Detail: SE 2 ft at 7 seconds and SW 1 foot at 4 seconds. A slight
chance of showers with isolated tstms.
.SAT...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.
.SAT NIGHT...W winds around 10 kt, becoming NW after midnight.
Seas 2 to 3 ft. Wave Detail: W 2 ft at 4 seconds and SE 2 ft at
7 seconds.
.SUN...N winds 5 to 10 kt. Seas around 2 ft. Wave Detail: NW 2 ft
at 4 seconds and SE 2 ft at 8 seconds.
.SUN NIGHT THROUGH MON NIGHT...NE winds 5 to 10 kt. Seas around
2 ft. Wave Detail: NE 2 ft at 3 seconds and E 2 ft at 8 seconds.
.TUE THROUGH WED NIGHT...S winds around 10 kt. Seas 2 to 4 ft.
Wave Detail: E 4 ft at 8 seconds and SE 1 foot at 3 seconds.

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.

$$

ANZ256-301800-
Coastal Waters from Montauk NY to Marthas Vineyard extending out
to 20 nm South of Block Island-
105 AM EDT Sat Aug 30 2025

.REST OF TONIGHT...NW winds 10 to 15 kt. Seas 2 to 3 ft. Wave
Detail: W 2 ft at 4 seconds and SE 2 ft at 7 seconds.
.SAT...NW winds around 10 kt, becoming W 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 10 to 15 kt, becoming NW after midnight.
Seas 2 to 3 ft. Wave Detail: W 2 ft at 4 seconds and SE 2 ft at
7 seconds.
.SUN...N winds 5 to 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 N after midnight.
Seas around 2 ft. Wave Detail: SE 2 ft at 8 seconds and NE 1 foot
at 2 seconds.
.MON AND MON NIGHT...NE winds around 10 kt. Seas around 2 ft.
Wave Detail: NE 2 ft at 3 seconds and SE 2 ft at 9 seconds.
.TUE THROUGH WED NIGHT...S winds 10 to 15 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.

$$

ANZ232-301800-
Nantucket Sound-
105 AM EDT Sat Aug 30 2025

.REST OF TONIGHT...W winds around 10 kt. Seas around 2 ft. Wave
Detail: E 1 foot at 3 seconds and SW 1 foot at 4 seconds. A
chance of showers with isolated tstms.
.SAT...NW winds around 10 kt, becoming W in the afternoon. Seas
around 2 ft. Wave Detail: NW 1 foot at 3 seconds and E 1 foot at
4 seconds.
.SAT NIGHT...W winds 10 to 15 kt, becoming NW after midnight.
Seas around 2 ft. Wave Detail: W 1 foot at 3 seconds and SE
1 foot at 7 seconds.
.SUN...N winds 5 to 10 kt. Seas around 2 ft. Wave Detail: N
1 foot at 3 seconds and S 1 foot at 7 seconds.
.SUN NIGHT...E winds 5 to 10 kt, becoming N after midnight. Seas
1 foot or less. Wave Detail: NE 1 foot at 2 seconds and NW 1 foot
at 3 seconds.
.MON AND MON NIGHT...NE winds 5 to 10 kt. Seas around 2 ft. Wave
Detail: N 1 foot at 3 seconds and SE 1 foot at 7 seconds.
.TUE THROUGH WED NIGHT...S winds 10 to 15 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.

$$

ANZ233-301800-
Vineyard Sound-
105 AM EDT Sat Aug 30 2025

.REST OF TONIGHT...NW winds around 10 kt. Seas around 2 ft. Wave
Detail: W 1 foot at 4 seconds and SE 1 foot at 7 seconds. A
slight chance of showers with isolated tstms.
.SAT...NW winds around 10 kt, becoming W in the afternoon. Seas
around 2 ft. Wave Detail: NW 1 foot at 3 seconds and SE 1 foot at
7 seconds.
.SAT NIGHT...W winds 10 to 15 kt, becoming NW after midnight.
Seas around 2 ft. Wave Detail: SW 2 ft at 4 seconds and SE 1 foot
at 7 seconds.
.SUN...N winds 5 to 10 kt. 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 7 seconds, becoming N 1 foot at 2 seconds and W 1 foot at
4 seconds.
.SUN NIGHT...S 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 5 seconds.
.MON AND MON NIGHT...NE winds 5 to 10 kt. Seas around 2 ft. Wave
Detail: N 1 foot at 2 seconds and S 1 foot at 6 seconds.
.TUE THROUGH WED 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.

$$

ANZ234-301800-
Buzzards Bay-
105 AM EDT Sat Aug 30 2025

.REST OF TONIGHT...NW winds around 10 kt. Seas 1 foot or less.
Wave Detail: SW 1 foot at 4 seconds and SE 1 foot at 8 seconds. A
slight chance of showers with isolated tstms.
.SAT...NW winds around 10 kt, becoming SW in the afternoon. Seas
1 foot or less, then around 2 ft in the afternoon. Wave Detail:
NW 1 foot at 3 seconds and SE 1 foot at 7 seconds, becoming SW
1 foot at 3 seconds and SE 1 foot at 7 seconds.
.SAT NIGHT...NW winds around 10 kt. 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
1 foot or less. Wave Detail: N 1 foot at 3 seconds and S 1 foot
at 7 seconds.
.SUN NIGHT...S 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 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 S 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.

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.

$$

ANZ235-301800-
Rhode Island Sound-
105 AM EDT Sat Aug 30 2025

.REST OF TONIGHT...NW winds around 10 kt. Seas around 2 ft. Wave
Detail: SE 2 ft at 5 seconds and W 1 foot at 4 seconds.
.SAT...NW winds around 10 kt, becoming W in the afternoon. Seas
around 2 ft. Wave Detail: NW 2 ft at 3 seconds and SE 2 ft at
7 seconds.
.SAT NIGHT...NW winds 10 to 15 kt. Seas around 2 ft. Wave Detail:
W 2 ft at 4 seconds and SE 2 ft at 7 seconds.
.SUN...N winds 5 to 10 kt, becoming SW in the afternoon. Seas
around 2 ft. Wave Detail: N 2 ft at 3 seconds and SE 2 ft at
7 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 NE 1 foot at
2 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 2 seconds.
.TUE THROUGH WED NIGHT...S winds 10 to 15 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.

$$

ANZ237-301800-
Block Island Sound-
105 AM EDT Sat Aug 30 2025

.REST OF TONIGHT...NW winds 10 to 15 kt. Seas around 2 ft. Wave
Detail: NW 1 foot at 3 seconds and S 1 foot at 5 seconds.
.SAT...NW winds around 10 kt, becoming W in the afternoon. Seas
around 2 ft. Wave Detail: SE 2 ft at 7 seconds and NW 1 foot at
3 seconds.
.SAT NIGHT...NW winds around 10 kt. Seas around 2 ft. Wave
Detail: SE 2 ft at 7 seconds and W 1 foot at 3 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
3 seconds.
.MON AND MON NIGHT...NE winds 5 to 10 kt. Seas around 2 ft. Wave
Detail: SE 2 ft at 6 seconds and NE 1 foot at 2 seconds.
.TUE THROUGH WED NIGHT...S winds 5 to 10 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.

$$

ANZ230-301800-
Boston Harbor-
105 AM EDT Sat Aug 30 2025

.REST OF TONIGHT...NW winds 5 to 10 kt. Waves 1 foot or less.
.SAT...NW winds around 10 kt, becoming W in the afternoon. Waves
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...S winds 5 to 10 kt, becoming W after midnight. Waves
1 foot or less.
.MON AND MON NIGHT...NW 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.

$$

ANZ236-301800-
Narragansett Bay-
105 AM EDT Sat Aug 30 2025

.REST OF TONIGHT...NW winds 5 to 10 kt. Waves 1 foot or less.
.SAT...NW winds 5 to 10 kt, becoming W in the afternoon. Waves
around 2 ft.
.SAT NIGHT...NW winds 5 to 10 kt. 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 NW after midnight.
Waves 1 foot or less.
.MON AND MON NIGHT...N winds 5 to 10 kt. Waves 1 foot or less.
.TUE THROUGH WED NIGHT...S winds 5 to 10 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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