160
FZUS51 KBOX 200504
CWFBOX

Coastal Waters Forecast for Massachusetts and Rhode Island
National Weather Service Boston/Norton MA
104 AM EDT Sun Apr 20 2025

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

ANZ200-201800-
104 AM EDT Sun Apr 20 2025

.Synopsis for Massachusetts and Rhode Island coastal waters...
NW winds today with no precipitation. Another high pres builds over
the region for Mon, with another front passing over the waters Tue.
Another high pres should arrive for Wed. High pressure maintains
control through Thurs. Periodic chances for rainfall Friday through
next weekend.

$$

ANZ250-201800-
Coastal waters east of Ipswich Bay and the Stellwagen Bank
National Marine Sanctuary-
104 AM EDT Sun Apr 20 2025

...SMALL CRAFT ADVISORY IN EFFECT THROUGH THIS EVENING...

.REST OF TONIGHT...W winds 15 to 20 kt with gusts up to 25 kt.
Seas 3 to 4 ft. Wave Detail: W 3 ft at 4 seconds and S 3 ft at
7 seconds.
.SUN...NW winds 15 to 20 kt with gusts up to 25 kt. Seas 3 to
5 ft. Wave Detail: W 4 ft at 4 seconds and SE 2 ft at 8 seconds.
.SUN NIGHT...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 4 seconds and SE 1 foot at 7 seconds.
.MON...N winds 5 to 10 kt, becoming SE in the afternoon. Seas
around 2 ft. Wave Detail: N 2 ft at 5 seconds.
.MON NIGHT AND TUE...S winds 10 to 15 kt with gusts up to 25 kt.
Seas 2 to 4 ft. Wave Detail: S 3 ft at 4 seconds. Showers likely
through the day. A chance of showers in the afternoon.
.TUE NIGHT...SW winds 10 to 15 kt with gusts up to 20 kt,
becoming W after midnight. Seas 2 to 4 ft. Wave Detail: SE 3 ft
at 7 seconds and SW 2 ft at 4 seconds.
.WED THROUGH THU 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.

$$

ANZ251-201800-
Massachusetts Bay and Ipswich Bay-
104 AM EDT Sun Apr 20 2025

.REST OF TONIGHT...W winds 15 to 20 kt with gusts up to 25 kt.
Seas 2 to 3 ft. Wave Detail: W 2 ft at 3 seconds and SE 1 foot at
6 seconds.
.SUN...NW winds 15 to 20 kt with gusts up to 25 kt. Seas 2 to
3 ft. Wave Detail: NW 3 ft at 4 seconds and SE 1 foot at
8 seconds.
.SUN NIGHT...NW 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: N 2 ft at 5 seconds.
.MON...N winds around 5 kt, becoming SE 10 to 15 kt in the
afternoon. Seas 1 foot or less, then around 2 ft in the
afternoon. Wave Detail: N 1 foot at 4 seconds, becoming E 2 ft at
5 seconds and NW 1 foot at 2 seconds.
.MON NIGHT AND TUE...SW winds 10 to 15 kt with gusts up to 20 kt.
Seas 2 to 3 ft. Wave Detail: S 2 ft at 3 seconds and SE 1 foot at
12 seconds. A chance of showers in the evening, then showers
likely through the day. A chance of showers in the afternoon.
.TUE NIGHT...W winds 10 to 15 kt. Seas around 2 ft. Wave Detail:
SE 2 ft at 6 seconds and SW 1 foot at 3 seconds.
.WED THROUGH THU NIGHT...S 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.

$$

ANZ231-201800-
Cape Cod Bay-
104 AM EDT Sun Apr 20 2025

.REST OF TONIGHT...W winds 10 to 15 kt with gusts up to 20 kt.
Seas 2 to 3 ft. Wave Detail: W 2 ft at 3 seconds and S 2 ft at
7 seconds.
.SUN...NW winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to
3 ft. Wave Detail: NW 2 ft at 4 seconds and S 2 ft at 8 seconds.
.SUN NIGHT...NW winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: NW
2 ft at 4 seconds and SE 1 foot at 7 seconds.
.MON...N winds around 5 kt, becoming SE in the afternoon. Seas
1 foot or less. Wave Detail: N 1 foot at 4 seconds.
.MON NIGHT AND TUE...SW winds 10 to 15 kt with gusts up to 20 kt.
Seas around 2 ft. Wave Detail: S 2 ft at 4 seconds and SE 1 foot
at 12 seconds. Showers likely through the day. A chance of
showers in the afternoon.
.TUE NIGHT...SW winds 10 to 15 kt with gusts up to 20 kt,
becoming W 5 to 10 kt after midnight. Seas around 2 ft. Wave
Detail: SW 2 ft at 3 seconds and SE 2 ft at 7 seconds.
.WED THROUGH THU NIGHT...S 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.

$$

ANZ254-201800-
Coastal waters from Provincetown MA to Chatham MA to Nantucket MA
out 20 nm-
104 AM EDT Sun Apr 20 2025

...SMALL CRAFT ADVISORY IN EFFECT THROUGH THIS EVENING...

.REST OF TONIGHT...W winds 15 to 20 kt with gusts up to 25 kt.
Seas 5 to 7 ft. Wave Detail: S 6 ft at 8 seconds and W 2 ft at
4 seconds.
.SUN...NW winds 15 to 20 kt, diminishing to 10 to 15 kt in the
afternoon. Gusts up to 25 kt. Seas 4 to 6 ft. Wave Detail: S 5 ft
at 8 seconds and NW 3 ft at 4 seconds.
.SUN NIGHT...NW winds 10 to 15 kt with gusts up to 20 kt,
becoming N 5 to 10 kt after midnight. Seas 3 to 5 ft. Wave
Detail: S 4 ft at 8 seconds and NW 3 ft at 5 seconds.
.MON...N winds around 5 kt, becoming SE in the afternoon. Seas
2 to 3 ft. Wave Detail: N 2 ft at 5 seconds and S 2 ft at
7 seconds.
.MON NIGHT...S winds 5 to 10 kt, increasing to 10 to 15 kt with
gusts up to 20 kt after midnight. Seas 2 to 3 ft. Wave Detail: SE
3 ft at 6 seconds and W 2 ft at 4 seconds. A chance of showers
after midnight.
.TUE...S winds 15 to 20 kt. Seas 3 to 5 ft. Wave Detail: S 4 ft
at 5 seconds and NW 1 foot at 4 seconds. A chance of showers.
.TUE NIGHT...SW winds 10 to 15 kt with gusts up to 20 kt,
becoming W after midnight. Seas 3 to 5 ft.
.WED AND WED NIGHT...W winds 5 to 10 kt, becoming S. Seas 2 to
4 ft.
.THU AND THU NIGHT...SE winds 5 to 10 kt, becoming S. 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.

$$

ANZ255-201800-
Coastal Waters extending out to 25 nm South of Marthas Vineyard
and Nantucket-
104 AM EDT Sun Apr 20 2025

...SMALL CRAFT ADVISORY IN EFFECT THROUGH THIS EVENING...

.REST OF TONIGHT...W winds 15 to 20 kt with gusts up to 25 kt.
Seas 5 to 8 ft. Wave Detail: SW 8 ft at 8 seconds and W 1 foot at
4 seconds.
.SUN...NW winds 15 to 20 kt, diminishing to 10 to 15 kt in the
afternoon. Seas 5 to 7 ft. Wave Detail: SW 7 ft at 8 seconds and
NW 1 foot at 4 seconds.
.SUN NIGHT...NW winds 5 to 10 kt. Seas 3 to 5 ft. Wave Detail: S
5 ft at 8 seconds and NW 1 foot at 4 seconds.
.MON...NE winds around 5 kt, becoming S in the afternoon. Seas
2 to 3 ft. Wave Detail: S 3 ft at 7 seconds and NW 1 foot at
3 seconds.
.MON NIGHT...S winds 10 to 15 kt. Gusts up to 20 kt after
midnight. Seas 2 to 4 ft. Wave Detail: S 3 ft at 4 seconds. A
chance of showers after midnight.
.TUE...S winds 15 to 20 kt with gusts up to 25 kt. Seas 3 to
5 ft. Wave Detail: S 5 ft at 6 seconds. A chance of showers.
.TUE NIGHT...SW winds 10 to 15 kt with gusts up to 20 kt,
becoming W after midnight. Seas 3 to 5 ft.
.WED AND WED NIGHT...W winds 5 to 10 kt, becoming S. Seas 2 to
4 ft.
.THU AND THU NIGHT...S 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.

$$

ANZ256-201800-
Coastal Waters from Montauk NY to Marthas Vineyard extending out
to 20 nm South of Block Island-
104 AM EDT Sun Apr 20 2025

...SMALL CRAFT ADVISORY IN EFFECT THROUGH THIS EVENING...

.REST OF TONIGHT...W winds 15 to 20 kt with gusts up to 25 kt.
Seas 6 to 7 ft. Wave Detail: S 7 ft at 8 seconds and W 1 foot at
4 seconds.
.SUN...NW winds 15 to 20 kt, diminishing to 10 to 15 kt in the
afternoon. Seas 5 to 7 ft. Wave Detail: S 6 ft at 8 seconds and
NW 2 ft at 3 seconds.
.SUN NIGHT...NW winds around 10 kt, becoming N after midnight.
Seas 2 to 4 ft. Wave Detail: S 4 ft at 8 seconds and NW 1 foot at
3 seconds.
.MON...NE winds around 5 kt, becoming S in the afternoon. Seas
2 to 3 ft. Wave Detail: S 3 ft at 7 seconds.
.MON NIGHT...S winds 10 to 15 kt, increasing to 15 to 20 kt after
midnight. Seas 2 to 4 ft. Wave Detail: S 3 ft at 5 seconds. A
chance of showers after midnight.
.TUE...SW winds 15 to 20 kt with gusts up to 25 kt. Seas 3 to
5 ft. Wave Detail: SW 5 ft at 5 seconds. A chance of showers.
.TUE NIGHT...SW winds 10 to 15 kt with gusts up to 20 kt,
becoming NW after midnight. Seas 3 to 5 ft.
.WED AND WED NIGHT...W winds 5 to 10 kt. Seas 2 to 4 ft.
.THU AND THU NIGHT...SE winds 5 to 10 kt, becoming S. 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.

$$

ANZ232-201800-
Nantucket Sound-
104 AM EDT Sun Apr 20 2025

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

$$

ANZ233-201800-
Vineyard Sound-
104 AM EDT Sun Apr 20 2025

...SMALL CRAFT ADVISORY IN EFFECT UNTIL 7 AM EDT THIS MORNING...

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

$$

ANZ234-201800-
Buzzards Bay-
104 AM EDT Sun Apr 20 2025

.REST OF TONIGHT...W winds 10 to 15 kt with gusts up to 20 kt.
Seas 3 to 4 ft. Wave Detail: SW 4 ft at 8 seconds and W 2 ft at
4 seconds.
.SUN...NW winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to
3 ft. Wave Detail: SW 3 ft at 8 seconds and W 2 ft at 4 seconds.
.SUN NIGHT...N winds 5 to 10 kt. Seas around 2 ft in the evening,
then 1 foot or less. Wave Detail: SW 2 ft at 7 seconds and NW
1 foot at 3 seconds, becoming NW 1 foot at 3 seconds and S 1 foot
at 7 seconds.
.MON...NE winds around 5 kt, becoming S in the afternoon. Seas
1 foot or less. Wave Detail: NW 1 foot at 4 seconds and S 1 foot
at 6 seconds.
.MON NIGHT AND TUE...SW winds 10 to 15 kt with gusts up to 20 kt.
Seas 2 to 3 ft. Wave Detail: S 3 ft at 5 seconds. Showers likely
through the day. A chance of showers in the afternoon.
.TUE NIGHT...SW winds 10 to 15 kt with gusts up to 20 kt,
becoming NW 5 to 10 kt after midnight. Seas 2 to 3 ft. Wave
Detail: SW 3 ft at 5 seconds.
.WED THROUGH THU NIGHT...S 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.

$$

ANZ235-201800-
Rhode Island Sound-
104 AM EDT Sun Apr 20 2025

...SMALL CRAFT ADVISORY IN EFFECT THROUGH THIS EVENING...

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

$$

ANZ237-201800-
Block Island Sound-
104 AM EDT Sun Apr 20 2025

...SMALL CRAFT ADVISORY IN EFFECT THROUGH THIS EVENING...

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

$$

ANZ230-201800-
Boston Harbor-
104 AM EDT Sun Apr 20 2025

.REST OF TONIGHT...W winds 15 to 20 kt with gusts up to 25 kt.
Waves around 2 ft.
.SUN...NW winds 15 to 20 kt with gusts up to 25 kt. Waves around
2 ft.
.SUN NIGHT...NW winds 10 to 15 kt with gusts up to 20 kt,
diminishing to 5 to 10 kt after midnight. Waves around 2 ft in
the evening, then 1 foot or less.
.MON...N winds around 5 kt, becoming SE in the afternoon. Waves
1 foot or less, then around 2 ft in the afternoon.
.MON NIGHT...S winds 10 to 15 kt. Waves around 2 ft. A chance of
showers in the evening, then showers likely after midnight.
.TUE...SW winds 10 to 15 kt. Waves around 2 ft. Showers likely in
the morning.
.TUE NIGHT...W winds 10 to 15 kt. Waves around 2 ft.
.WED THROUGH THU NIGHT...S winds 5 to 10 kt. Waves 1 foot or
less.

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.

$$

ANZ236-201800-
Narragansett Bay-
104 AM EDT Sun Apr 20 2025

.REST OF TONIGHT...W winds 10 to 15 kt with gusts up to 20 kt.
Waves 2 to 4 ft.
.SUN...NW winds 10 to 15 kt with gusts up to 20 kt. Waves 2 to
3 ft.
.SUN NIGHT...N winds 5 to 10 kt. Waves 2 to 3 ft.
.MON...NE winds around 5 kt, becoming S in the afternoon. Waves
1 foot or less.
.MON NIGHT AND TUE...SW winds 10 to 15 kt with gusts up to 20 kt.
Waves 2 to 3 ft. Showers likely through the day.
.TUE NIGHT...W winds around 10 kt, becoming NW after midnight.
Waves 2 to 3 ft.
.WED THROUGH THU NIGHT...SW winds 5 to 10 kt. Waves 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.

$$

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