519
FZUS51 KBOX 182103
CWFBOX

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

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

ANZ200-191000-
403 PM EST Tue Nov 18 2025

.Synopsis for Massachusetts and Rhode Island coastal waters...
Gusty winds this afternoon, weakening overnight into early Tuesday.
High pres 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.

$$

ANZ250-191000-
Coastal waters east of Ipswich Bay and the Stellwagen Bank
National Marine Sanctuary-
403 PM EST Tue Nov 18 2025

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

.TONIGHT...W winds 10 to 15 kt. Gusts up to 20 kt this 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 NE 1 foot
at 6 seconds.
.FRI AND FRI NIGHT...W winds 10 to 15 kt with gusts up to 25 kt.
Seas 2 to 4 ft. Wave Detail: SW 3 ft at 4 seconds and SE 1 foot
at 7 seconds. A chance of rain through the night.
.SAT THROUGH SUN NIGHT...W 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.

$$

ANZ251-191000-
Massachusetts Bay and Ipswich Bay-
403 PM EST Tue Nov 18 2025

.TONIGHT...W winds 10 to 15 kt. Gusts up to 20 kt this evening.
Seas around 2 ft. Wave Detail: W 2 ft at 4 seconds and E 1 foot
at 12 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 7 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 5 seconds.
.FRI AND FRI NIGHT...W winds 10 to 15 kt with gusts up to 20 kt.
Seas around 2 ft. Wave Detail: S 2 ft at 3 seconds and NE 1 foot
at 6 seconds.
.SAT THROUGH SUN NIGHT...W 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.

$$

ANZ231-191000-
Cape Cod Bay-
403 PM EST Tue Nov 18 2025

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

$$

ANZ254-191000-
Coastal waters from Provincetown MA to Chatham MA to Nantucket MA
out 20 nm-
403 PM EST Tue Nov 18 2025

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

.TONIGHT...W winds 10 to 15 kt. Gusts up to 20 kt this evening.
Seas 2 to 4 ft. Wave Detail: W 4 ft at 6 seconds and SE 1 foot at
10 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 10 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 NE
1 foot at 8 seconds, becoming W 1 foot at 5 seconds and NE 1 foot
at 6 seconds.
.THU NIGHT...NE winds around 5 kt, becoming NW after midnight.
Seas around 2 ft. Wave Detail: E 2 ft at 6 seconds and NW 1 foot
at 3 seconds.
.FRI...W winds 5 to 10 kt, becoming SW 10 to 15 kt with gusts up
to 20 kt in the afternoon. Seas 2 to 3 ft. Wave Detail: S 2 ft at
5 seconds.
.FRI NIGHT...SW winds around 15 kt, becoming W after midnight.
Gusts up to 20 kt. Seas 2 to 4 ft. A chance of rain.
.SAT THROUGH SUN NIGHT...W 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.

$$

ANZ255-191000-
Coastal Waters extending out to 25 nm South of Marthas Vineyard
and Nantucket-
403 PM EST Tue Nov 18 2025

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

.TONIGHT...W winds 10 to 15 kt. Gusts up to 20 kt this evening.
Seas 3 to 5 ft, subsiding to 2 to 3 ft after midnight. Wave
Detail: W 4 ft at 6 seconds and SE 1 foot at 12 seconds, becoming
W 3 ft at 6 seconds and E 1 foot at 12 seconds.
.WED...NW winds 5 to 10 kt, becoming N in the afternoon. Seas
2 to 3 ft. Wave Detail: W 2 ft at 6 seconds and SE 1 foot at
11 seconds.
.WED NIGHT...NE winds 5 to 10 kt. Seas around 2 ft. Wave Detail:
SW 2 ft at 5 seconds and NE 1 foot at 9 seconds.
.THU...NE winds 5 to 10 kt. Seas around 2 ft. Wave Detail: SW
2 ft at 6 seconds and NE 1 foot at 4 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 S 2 ft at
6 seconds.
.FRI...SW winds 5 to 10 kt, increasing to 15 to 20 kt in the
afternoon. Seas 2 to 4 ft. Wave Detail: S 3 ft at 5 seconds.
.FRI NIGHT...SW winds 15 to 20 kt, becoming W after midnight.
Seas 3 to 5 ft. A chance of rain.
.SAT...NW winds 10 to 15 kt with gusts up to 20 kt. Seas 3 to
5 ft. A chance of rain.
.SAT NIGHT...N winds 10 to 15 kt. Seas 3 to 5 ft.
.SUN AND SUN NIGHT...W winds around 10 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.

$$

ANZ256-191000-
Coastal Waters from Montauk NY to Marthas Vineyard extending out
to 20 nm South of Block Island-
403 PM EST Tue Nov 18 2025

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

.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 9 seconds.
.WED...N winds around 5 kt. Seas around 2 ft. Wave Detail: NW
2 ft at 5 seconds and S 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: SW 1 foot at 5 seconds
and E 1 foot at 10 seconds, becoming SW 1 foot at 4 seconds and
NE 1 foot at 6 seconds.
.THU...NE winds 5 to 10 kt. Seas around 2 ft. Wave Detail: NE
1 foot at 4 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: S 2 ft at 6 seconds.
.FRI...SW winds 10 to 15 kt, increasing to 15 to 20 kt in the
afternoon. Seas 2 to 4 ft. Wave Detail: S 3 ft at 5 seconds.
.FRI NIGHT...SW winds 15 to 20 kt, becoming NW after midnight.
Seas 3 to 5 ft. A chance of rain.
.SAT THROUGH SUN NIGHT...W 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.

$$

ANZ232-191000-
Nantucket Sound-
403 PM EST Tue Nov 18 2025

.TONIGHT...W winds 10 to 15 kt. Seas 2 to 3 ft. Wave Detail: W
3 ft at 4 seconds and SE 1 foot at 9 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 NW 1 foot at 4 seconds and E 1 foot at
10 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 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 4 seconds.
.THU NIGHT...N winds around 5 kt. Seas 1 foot or less. Wave
Detail: NE 1 foot at 4 seconds and SW 1 foot at 5 seconds.
.FRI...SW winds 5 to 10 kt, increasing to 10 to 15 kt with gusts
up to 20 kt in the afternoon. Seas 2 to 3 ft. Wave Detail: SW
2 ft at 4 seconds and SE 1 foot at 5 seconds.
.FRI NIGHT...SW winds around 15 kt, becoming W after midnight.
Gusts up to 20 kt. Seas 2 to 3 ft. A chance of rain.
.SAT THROUGH SUN NIGHT...W 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.

$$

ANZ233-191000-
Vineyard Sound-
403 PM EST Tue Nov 18 2025

.TONIGHT...NW winds 10 to 15 kt, becoming W 5 to 10 kt after
midnight. Seas 2 to 3 ft. Wave Detail: W 2 ft at 4 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 9 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, becoming NW after midnight.
Seas 1 foot or less. Wave Detail: E 1 foot at 4 seconds and SW
1 foot at 5 seconds.
.FRI...SW winds 5 to 10 kt, increasing to 10 to 15 kt with gusts
up to 20 kt in the afternoon. Seas 2 to 3 ft. Wave Detail: S 2 ft
at 5 seconds.
.FRI NIGHT...SW winds around 15 kt with gusts up to 20 kt,
becoming NW after midnight. Seas 2 to 3 ft. A chance of rain in
the evening.
.SAT THROUGH SUN NIGHT...W 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.

$$

ANZ234-191000-
Buzzards Bay-
403 PM EST Tue Nov 18 2025

.TONIGHT...W winds 10 to 15 kt, diminishing to 5 to 10 kt after
midnight. Seas around 2 ft this evening, then 1 foot or less.
Wave Detail: W 2 ft at 4 seconds and S 1 foot at 8 seconds,
becoming W 1 foot at 5 seconds and S 1 foot at 8 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 around 5 kt. Seas 1 foot or less. Wave
Detail: SW 1 foot at 5 seconds and NE 1 foot at 9 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 4 seconds.
.THU NIGHT...N winds around 5 kt. Seas 1 foot or less. Wave
Detail: E 1 foot at 3 seconds and SW 1 foot at 5 seconds.
.FRI AND FRI NIGHT...NW winds 10 to 15 kt with gusts up to 20 kt.
Seas 2 to 3 ft. Wave Detail: S 2 ft at 5 seconds.
.SAT THROUGH SUN NIGHT...W winds 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.

$$

ANZ235-191000-
Rhode Island Sound-
403 PM EST Tue Nov 18 2025

.TONIGHT...NW winds 10 to 15 kt, diminishing to 5 to 10 kt after
midnight. Seas 2 to 3 ft. Wave Detail: W 2 ft at 4 seconds and S
1 foot at 9 seconds.
.WED...N winds around 5 kt. Seas around 2 ft. 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.
.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 6 seconds.
.THU NIGHT...NE winds around 5 kt, becoming NW after midnight.
Seas around 2 ft. Wave Detail: E 2 ft at 6 seconds and S 1 foot
at 6 seconds.
.FRI...SW winds 10 to 15 kt, increasing to 15 to 20 kt in the
afternoon. Seas 2 to 3 ft. Wave Detail: SW 3 ft at 4 seconds and
SE 1 foot at 7 seconds.
.FRI NIGHT...SW winds around 15 kt, becoming NW after midnight.
Gusts up to 20 kt. Seas 2 to 4 ft. A chance of rain in the
evening.
.SAT THROUGH SUN NIGHT...W 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.

$$

ANZ237-191000-
Block Island Sound-
403 PM EST Tue Nov 18 2025

.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: W
1 foot at 4 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 SE 1 foot at 8 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 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: S 1 foot at 6 seconds.
.FRI AND FRI NIGHT...NW winds 10 to 15 kt with gusts up to 20 kt.
Seas 2 to 3 ft. Wave Detail: W 3 ft at 4 seconds and SE 1 foot at
6 seconds.
.SAT THROUGH SUN NIGHT...W 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.

$$

ANZ230-191000-
Boston Harbor-
403 PM EST Tue Nov 18 2025

.TONIGHT...W winds 10 to 15 kt, diminishing to 5 to 10 kt after
midnight. Waves around 2 ft this 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 AND FRI NIGHT...W winds 10 to 15 kt. Waves around 2 ft.
.SAT THROUGH SUN NIGHT...W 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.

$$

ANZ236-191000-
Narragansett Bay-
403 PM EST Tue Nov 18 2025

.TONIGHT...W winds 5 to 10 kt. Waves around 2 ft this 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 AND FRI NIGHT...NW winds 10 to 15 kt with gusts up to 20 kt.
Waves around 2 ft.
.SAT THROUGH SUN NIGHT...W 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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