Coastal Waters Forecast
Issued by NWS Boston, MA

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064
FZUS51 KBOX 181803
CWFBOX

Coastal Waters Forecast for Massachusetts and Rhode Island
National Weather Service Boston/Norton MA
103 PM EST Tue Nov 18 2025

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

ANZ200-190700-
103 PM EST Tue Nov 18 2025

.Synopsis for Massachusetts and Rhode Island coastal waters...
Gusty winds linger today, then high pressure moves into the waters
Wednesday and Thursday bringing light winds. Low pres will track
well south of the waters Wednesday and Wednesday night. A cold front
approaches from the Great Lakes Friday and moves south of the waters
Friday night into Saturday. Rain showers possible.

$$

ANZ250-190700-
Coastal waters east of Ipswich Bay and the Stellwagen Bank
National Marine Sanctuary-
103 PM EST Tue Nov 18 2025

...SMALL CRAFT ADVISORY IN EFFECT UNTIL 7 PM EST THIS EVENING...

.THIS AFTERNOON...W winds 15 to 20 kt with gusts up to 25 kt.
Seas 3 to 5 ft. Wave Detail: W 4 ft at 5 seconds and SE 1 foot at
12 seconds.
.TONIGHT...W winds 10 to 15 kt. Gusts up to 20 kt in the evening.
Seas 2 to 4 ft. Wave Detail: W 3 ft at 5 seconds and SE 1 foot at
11 seconds.
.WED...NW winds 5 to 10 kt. Seas around 2 ft. Wave Detail: W 2 ft
at 4 seconds and E 1 foot at 11 seconds.
.WED NIGHT...N winds around 5 kt. Seas 1 foot or less. Wave
Detail: NW 1 foot at 3 seconds and E 1 foot at 11 seconds.
.THU...NE winds around 5 kt. Seas 1 foot or less. Wave Detail: NW
1 foot at 2 seconds and E 1 foot at 10 seconds.
.THU NIGHT...E winds around 5 kt, becoming W after midnight. Seas
1 foot or less. Wave Detail: NW 1 foot at 2 seconds and E 1 foot
at 10 seconds.
.FRI...SW winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to
3 ft.
.FRI NIGHT...W winds around 15 kt with gusts up to 25 kt. Seas
2 to 4 ft. A chance of rain.
.SAT AND SAT NIGHT...NW winds 10 to 15 kt. 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.

$$

ANZ251-190700-
Massachusetts Bay and Ipswich Bay-
103 PM EST Tue Nov 18 2025

.THIS AFTERNOON...W winds 15 to 20 kt with gusts up to 25 kt.
Seas 2 to 3 ft. Wave Detail: W 3 ft at 4 seconds and E 1 foot at
12 seconds.
.TONIGHT...W winds 10 to 15 kt. Gusts up to 20 kt in the evening.
Seas around 2 ft. Wave Detail: W 2 ft at 4 seconds and E 1 foot
at 11 seconds.
.WED...NW winds 5 to 10 kt. Seas 1 foot or less. Wave Detail: NW
1 foot at 3 seconds and NE 1 foot at 10 seconds.
.WED NIGHT...N winds around 5 kt. Seas 1 foot or less. Wave
Detail: NW 1 foot at 2 seconds and NE 1 foot at 8 seconds.
.THU...NE winds around 5 kt. Seas 1 foot or less. Wave Detail: NW
1 foot at 2 seconds and NE 1 foot at 9 seconds.
.THU NIGHT...N winds around 5 kt, becoming W after midnight. Seas
1 foot or less. Wave Detail: NW 1 foot at 2 seconds and NE 1 foot
at 6 seconds.
.FRI THROUGH SAT NIGHT...NW winds 10 to 15 kt with gusts up to
20 kt. Seas 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.

$$

ANZ231-190700-
Cape Cod Bay-
103 PM EST Tue Nov 18 2025

.THIS AFTERNOON...W winds 10 to 15 kt with gusts up to 25 kt.
Seas 2 to 3 ft. Wave Detail: W 3 ft at 5 seconds and NE 1 foot at
11 seconds.
.TONIGHT...W winds 10 to 15 kt with gusts up to 20 kt,
diminishing to 5 to 10 kt after midnight. Seas around 2 ft. Wave
Detail: NW 2 ft at 4 seconds and E 1 foot at 11 seconds.
.WED...W winds 5 to 10 kt, becoming NW in the afternoon. Seas
1 foot or less. Wave Detail: NW 1 foot at 4 seconds and NE 1 foot
at 10 seconds.
.WED NIGHT...N winds around 5 kt. Seas 1 foot or less. Wave
Detail: NW 1 foot at 4 seconds and NE 1 foot at 9 seconds.
.THU...NE winds around 5 kt. Seas 1 foot or less. Wave Detail: N
1 foot at 3 seconds and NE 1 foot at 7 seconds.
.THU NIGHT...NE winds around 5 kt, becoming W around 5 kt after
midnight. Seas 1 foot or less. Wave Detail: NE 1 foot at
5 seconds.
.FRI...SW winds 10 to 15 kt with gusts up to 20 kt. Seas around
2 ft.
.FRI NIGHT...W winds 10 to 15 kt with gusts up to 20 kt. Seas
around 2 ft. A chance of rain.
.SAT AND SAT NIGHT...NW winds 10 to 15 kt with gusts up to 20 kt,
diminishing to 5 to 10 kt. Seas 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.

$$

ANZ254-190700-
Coastal waters from Provincetown MA to Chatham MA to Nantucket MA
out 20 nm-
103 PM EST Tue Nov 18 2025

...SMALL CRAFT ADVISORY IN EFFECT UNTIL 7 PM EST THIS EVENING...

.THIS AFTERNOON...W winds 15 to 20 kt with gusts up to 25 kt.
Seas 3 to 5 ft. Wave Detail: W 5 ft at 6 seconds and E 1 foot at
11 seconds.
.TONIGHT...W winds 10 to 15 kt. Gusts up to 20 kt in the evening.
Seas 2 to 4 ft. Wave Detail: W 4 ft at 6 seconds and SE 1 foot at
11 seconds.
.WED...NW winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: W 2 ft
at 5 seconds and SE 1 foot at 10 seconds.
.WED NIGHT...N winds around 5 kt. Seas around 2 ft. Wave Detail:
NW 2 ft at 5 seconds and E 1 foot at 11 seconds.
.THU...NE winds 5 to 10 kt. Seas 1 foot or less, then around 2 ft
in the afternoon. Wave Detail: SW 1 foot at 5 seconds and E
1 foot at 10 seconds, becoming SW 1 foot at 5 seconds and NE
1 foot at 7 seconds.
.THU NIGHT...NE winds around 5 kt, becoming NW after midnight.
Seas around 2 ft. Wave Detail: S 2 ft at 6 seconds.
.FRI...SW winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to
3 ft.
.FRI NIGHT...W winds around 15 kt with gusts up to 20 kt. Seas
2 to 4 ft. A chance of rain.
.SAT AND SAT NIGHT...NW winds 10 to 15 kt. 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.

$$

ANZ255-190700-
Coastal Waters extending out to 25 nm South of Marthas Vineyard
and Nantucket-
103 PM EST Tue Nov 18 2025

...SMALL CRAFT ADVISORY IN EFFECT UNTIL 7 PM EST THIS EVENING...

.THIS AFTERNOON...W winds 15 to 20 kt with gusts up to 25 kt.
Seas 4 to 6 ft. Wave Detail: W 6 ft at 7 seconds and E 1 foot at
13 seconds.
.TONIGHT...W winds 10 to 15 kt. Gusts up to 20 kt in the evening.
Seas 3 to 5 ft, subsiding to 2 to 3 ft after midnight. Wave
Detail: W 4 ft at 6 seconds and E 1 foot at 12 seconds, becoming
W 3 ft at 6 seconds and E 1 foot at 11 seconds.
.WED...NW winds 5 to 10 kt, becoming N in the afternoon. Seas
2 to 3 ft. Wave Detail: W 3 ft at 6 seconds and SE 1 foot at
12 seconds.
.WED NIGHT...NE winds 5 to 10 kt. Seas around 2 ft. Wave Detail:
SW 2 ft at 5 seconds and E 1 foot at 12 seconds.
.THU...NE winds 5 to 10 kt. Seas around 2 ft. Wave Detail: SW
1 foot at 6 seconds and NE 1 foot at 6 seconds.
.THU NIGHT...N winds 5 to 10 kt, becoming NW after midnight. Seas
around 2 ft. Wave Detail: NE 2 ft at 6 seconds and SW 1 foot at
6 seconds.
.FRI...SW winds 15 to 20 kt. Seas 2 to 4 ft.
.FRI NIGHT AND SAT...W winds 15 to 20 kt, becoming NW 10 to
15 kt. Seas 3 to 5 ft. A chance of rain.
.SAT NIGHT...N winds 10 to 15 kt. Seas 3 to 5 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.

$$

ANZ256-190700-
Coastal Waters from Montauk NY to Marthas Vineyard extending out
to 20 nm South of Block Island-
103 PM EST Tue Nov 18 2025

...SMALL CRAFT ADVISORY IN EFFECT UNTIL 7 PM EST THIS EVENING...

.THIS AFTERNOON...W winds 15 to 20 kt with gusts up to 25 kt.
Seas 3 to 5 ft. Wave Detail: W 5 ft at 5 seconds and S 1 foot at
10 seconds.
.TONIGHT...NW winds 10 to 15 kt with gusts up to 20 kt,
diminishing to 5 to 10 kt after midnight. Seas 2 to 4 ft. Wave
Detail: NW 3 ft at 5 seconds and S 1 foot at 11 seconds.
.WED...N winds around 5 kt. Seas around 2 ft. Wave Detail: NW
2 ft at 5 seconds and SE 1 foot at 11 seconds.
.WED NIGHT...NE winds 5 to 10 kt. Seas around 2 ft in the
evening, then 1 foot or less. Wave Detail: W 2 ft at 5 seconds
and E 1 foot at 11 seconds, becoming SW 1 foot at 5 seconds and
NE 1 foot at 10 seconds.
.THU...NE winds 5 to 10 kt. Seas around 2 ft. Wave Detail: NE
1 foot at 5 seconds and SW 1 foot at 6 seconds.
.THU NIGHT...NE winds around 5 kt, becoming W after midnight.
Seas around 2 ft. Wave Detail: E 2 ft at 6 seconds and SW 1 foot
at 6 seconds.
.FRI...SW winds 15 to 20 kt. Seas 2 to 4 ft.
.FRI NIGHT...W winds 15 to 20 kt. Seas 3 to 5 ft. A chance of
rain.
.SAT AND SAT NIGHT...N winds 10 to 15 kt. Gusts up to 20 kt. Seas
3 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.

$$

ANZ232-190700-
Nantucket Sound-
103 PM EST Tue Nov 18 2025

.THIS AFTERNOON...W winds 15 to 20 kt with gusts up to 25 kt.
Seas 2 to 3 ft. Wave Detail: W 3 ft at 4 seconds and E 1 foot at
10 seconds.
.TONIGHT...W winds 10 to 15 kt. Seas 2 to 3 ft. Wave Detail: W
3 ft at 4 seconds and E 1 foot at 10 seconds.
.WED...NW winds 5 to 10 kt. Seas around 2 ft in the morning, then
1 foot or less. Wave Detail: W 1 foot at 4 seconds and SE 1 foot
at 10 seconds, becoming W 1 foot at 4 seconds and E 1 foot at
11 seconds.
.WED NIGHT...N winds 5 to 10 kt. Seas 1 foot or less. Wave
Detail: W 1 foot at 4 seconds and NE 1 foot at 11 seconds.
.THU...NE winds 5 to 10 kt. Seas 1 foot or less. Wave Detail: NE
1 foot at 4 seconds and SW 1 foot at 5 seconds.
.THU NIGHT...N winds around 5 kt. Seas 1 foot or less. Wave
Detail: NE 1 foot at 3 seconds and SW 1 foot at 5 seconds.
.FRI...SW winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to
3 ft.
.FRI NIGHT...W winds around 15 kt with gusts up to 20 kt. Seas
2 to 3 ft. A chance of rain.
.SAT AND SAT NIGHT...NW 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.

$$

ANZ233-190700-
Vineyard Sound-
103 PM EST Tue Nov 18 2025

.THIS AFTERNOON...W winds 15 to 20 kt. Seas 2 to 3 ft. Wave
Detail: W 3 ft at 5 seconds and S 1 foot at 10 seconds.
.TONIGHT...NW winds 10 to 15 kt, becoming W 5 to 10 kt after
midnight. Seas 2 to 3 ft. Wave Detail: W 3 ft at 5 seconds and S
1 foot at 9 seconds.
.WED...NW winds around 5 kt. Seas 1 foot or less. Wave Detail: W
1 foot at 5 seconds and S 1 foot at 8 seconds.
.WED NIGHT...N winds 5 to 10 kt. Seas 1 foot or less. Wave
Detail: SW 1 foot at 5 seconds and NE 1 foot at 10 seconds.
.THU...NE winds 5 to 10 kt. Seas 1 foot or less. Wave Detail: NE
1 foot at 2 seconds and SW 1 foot at 5 seconds.
.THU NIGHT...N winds around 5 kt, becoming NW after midnight.
Seas 1 foot or less. Wave Detail: NE 1 foot at 3 seconds and SW
1 foot at 5 seconds.
.FRI...SW winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to
3 ft.
.FRI NIGHT...W winds 10 to 15 kt with gusts up to 20 kt. Seas
2 to 3 ft. A chance of rain.
.SAT AND SAT NIGHT...NW winds 10 to 15 kt, diminishing to 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.

$$

ANZ234-190700-
Buzzards Bay-
103 PM EST Tue Nov 18 2025

.THIS AFTERNOON...W winds 15 to 20 kt. Seas 2 to 3 ft. Wave
Detail: W 3 ft at 5 seconds and S 1 foot at 10 seconds.
.TONIGHT...W winds 10 to 15 kt, diminishing to 5 to 10 kt after
midnight. Seas around 2 ft in the evening, then 1 foot or less.
Wave Detail: W 2 ft at 5 seconds and S 1 foot at 9 seconds,
becoming W 1 foot at 5 seconds and S 1 foot at 9 seconds.
.WED...NW winds around 5 kt. Seas 1 foot or less. Wave Detail: W
1 foot at 5 seconds and S 1 foot at 9 seconds.
.WED NIGHT...N winds around 5 kt. Seas 1 foot or less. Wave
Detail: SW 1 foot at 5 seconds and E 1 foot at 10 seconds.
.THU...NE winds 5 to 10 kt. Seas 1 foot or less. Wave Detail: NE
1 foot at 3 seconds and SW 1 foot at 5 seconds.
.THU NIGHT...N winds around 5 kt. Seas 1 foot or less. Wave
Detail: NE 1 foot at 3 seconds and SW 1 foot at 5 seconds.
.FRI THROUGH SAT NIGHT...NW 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.

$$

ANZ235-190700-
Rhode Island Sound-
103 PM EST Tue Nov 18 2025

.THIS AFTERNOON...W winds 15 to 20 kt. Seas 2 to 4 ft. Wave
Detail: W 3 ft at 5 seconds and S 1 foot at 9 seconds.
.TONIGHT...NW winds 10 to 15 kt, diminishing to 5 to 10 kt after
midnight. Seas 2 to 3 ft. Wave Detail: W 3 ft at 5 seconds and S
1 foot at 9 seconds.
.WED...N winds around 5 kt. Seas around 2 ft. Wave Detail: SW
2 ft at 7 seconds.
.WED NIGHT...N winds 5 to 10 kt. Seas 1 foot or less. Wave
Detail: SW 1 foot at 5 seconds and SE 1 foot at 9 seconds.
.THU...NE winds 5 to 10 kt. Seas 1 foot or less. Wave Detail: NE
1 foot at 4 seconds and S 1 foot at 6 seconds.
.THU NIGHT...NE winds around 5 kt, becoming NW after midnight.
Seas around 2 ft. Wave Detail: E 1 foot at 5 seconds and SW
1 foot at 6 seconds.
.FRI...SW winds 15 to 20 kt. Seas 2 to 3 ft.
.FRI NIGHT...W winds 10 to 15 kt with gusts up to 20 kt. Seas
2 to 4 ft. A chance of rain.
.SAT AND SAT NIGHT...NW 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.

$$

ANZ237-190700-
Block Island Sound-
103 PM EST Tue Nov 18 2025

.THIS AFTERNOON...W winds 10 to 15 kt with gusts up to 20 kt.
Seas 2 to 3 ft. Wave Detail: W 2 ft at 4 seconds and S 1 foot at
10 seconds.
.TONIGHT...NW winds 10 to 15 kt, diminishing to 5 to 10 kt after
midnight. Seas around 2 ft. Wave Detail: W 2 ft at 4 seconds and
S 1 foot at 9 seconds.
.WED...N winds around 5 kt. Seas 1 foot or less. Wave Detail: NW
1 foot at 4 seconds and S 1 foot at 9 seconds.
.WED NIGHT...N winds 5 to 10 kt. Seas 1 foot or less. Wave
Detail: SW 1 foot at 5 seconds and SE 1 foot at 9 seconds.
.THU...NE winds 5 to 10 kt. Seas 1 foot or less. Wave Detail: NE
1 foot at 5 seconds and S 1 foot at 6 seconds.
.THU NIGHT...NE winds around 5 kt, becoming W around 5 kt after
midnight. Seas 1 foot or less, then around 2 ft after midnight.
Wave Detail: E 1 foot at 5 seconds and S 1 foot at 6 seconds,
becoming S 1 foot at 6 seconds.
.FRI THROUGH SAT NIGHT...N 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.

$$

ANZ230-190700-
Boston Harbor-
103 PM EST Tue Nov 18 2025

.THIS AFTERNOON...W winds 10 to 15 kt with gusts up to 20 kt.
Waves around 2 ft.
.TONIGHT...W winds 10 to 15 kt, diminishing to 5 to 10 kt after
midnight. Waves around 2 ft in the evening, then 1 foot or less.
.WED...NW winds 5 to 10 kt. Waves 1 foot or less.
.WED NIGHT...NW winds around 5 kt. Waves 1 foot or less.
.THU...N winds around 5 kt. Waves 1 foot or less.
.THU NIGHT...N winds around 5 kt, becoming W after midnight.
Waves 1 foot or less.
.FRI THROUGH SAT NIGHT...NW 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.

$$

ANZ236-190700-
Narragansett Bay-
103 PM EST Tue Nov 18 2025

.THIS AFTERNOON...W winds 10 to 15 kt with gusts up to 20 kt.
Waves 2 to 3 ft.
.TONIGHT...W winds 5 to 10 kt. Waves around 2 ft in the evening,
then 1 foot or less.
.WED...N winds around 5 kt. Waves 1 foot or less.
.WED NIGHT...N winds around 5 kt. Waves 1 foot or less.
.THU...NE winds around 5 kt. Waves 1 foot or less.
.THU NIGHT...N winds around 5 kt, becoming NW after midnight.
Waves 1 foot or less.
.FRI THROUGH SAT NIGHT...NW 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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