554
FZUS51 KBOX 201105
CWFBOX

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

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

ANZ200-210000-
705 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 pres maintains control
through Thu. Periodic chances for rainfall Friday through next
weekend.

$$

ANZ250-210000-
Coastal waters east of Ipswich Bay and the Stellwagen Bank
National Marine Sanctuary-
705 AM EDT Sun Apr 20 2025

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

.TODAY...NW winds 15 to 20 kt with gusts up to 30 kt. Seas 3 to
5 ft. Wave Detail: W 4 ft at 5 seconds and SE 2 ft at 8 seconds.
.TONIGHT...NW winds 10 to 15 kt with gusts up to 25 kt. Seas 2 to
4 ft. Wave Detail: W 4 ft at 5 seconds and N 1 foot at 5 seconds.
.MON...N winds 5 to 10 kt, becoming SE 10 to 15 kt with gusts up
to 20 kt in the afternoon. Seas around 2 ft. Wave Detail: NW 2 ft
at 4 seconds and N 2 ft at 5 seconds.
.MON NIGHT...S 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 N 1 foot at
4 seconds. Showers likely after midnight.
.TUE...S winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to
4 ft. Wave Detail: SE 3 ft at 4 seconds and SE 1 foot at
10 seconds. Showers likely, mainly in the morning.
.TUE NIGHT...SW winds 10 to 15 kt with gusts up to 20 kt,
becoming NW after midnight. Seas 2 to 4 ft. Wave Detail: S 3 ft
at 6 seconds and W 2 ft at 3 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.

$$

ANZ251-210000-
Massachusetts Bay and Ipswich Bay-
705 AM EDT Sun Apr 20 2025

...SMALL CRAFT ADVISORY IN EFFECT UNTIL 1 PM EDT THIS AFTERNOON...

.TODAY...NW winds 15 to 20 kt with gusts up to 30 kt. Seas 2 to
3 ft. Wave Detail: W 3 ft at 4 seconds and N 1 foot at 4 seconds.
.TONIGHT...NW winds 10 to 15 kt with gusts up to 25 kt,
diminishing to 5 to 10 kt after midnight. Seas around 2 ft. Wave
Detail: NW 2 ft at 4 seconds and N 1 foot at 5 seconds.
.MON...N winds 5 to 10 kt, becoming SE 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: NW 1 foot at 3 seconds and N
1 foot at 5 seconds, becoming N 1 foot at 3 seconds and SE 1 foot
at 5 seconds.
.MON NIGHT...S winds 10 to 15 kt. Gusts up to 20 kt in the
evening. Seas around 2 ft. Wave Detail: SE 2 ft at 3 seconds and
NE 1 foot at 4 seconds. A chance of showers in the evening, then
showers likely after midnight.
.TUE...S winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to
3 ft. Wave Detail: SE 2 ft at 5 seconds and SE 1 foot at
10 seconds. Showers likely, mainly in the morning.
.TUE NIGHT...W winds 10 to 15 kt. Seas around 2 ft. Wave Detail:
SW 2 ft at 4 seconds and E 1 foot 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.

$$

ANZ231-210000-
Cape Cod Bay-
705 AM EDT Sun Apr 20 2025

...SMALL CRAFT ADVISORY IN EFFECT UNTIL 1 PM EDT THIS AFTERNOON...

.TODAY...NW winds 15 to 20 kt, diminishing to 10 to 15 kt this
afternoon. Gusts up to 25 kt. Seas 2 to 3 ft. Wave Detail: W 3 ft
at 5 seconds and S 2 ft at 8 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 3 ft. Wave
Detail: NW 2 ft at 5 seconds and N 1 foot at 5 seconds.
.MON...N winds 5 to 10 kt, becoming SE in the afternoon. Seas
1 foot or less. Wave Detail: N 1 foot at 5 seconds and S 1 foot
at 7 seconds.
.MON NIGHT...S winds 10 to 15 kt. Gusts up to 20 kt after
midnight. Seas 1 foot or less, then around 2 ft after midnight.
Wave Detail: S 1 foot at 2 seconds and N 1 foot at 5 seconds,
becoming S 1 foot at 3 seconds and N 1 foot at 5 seconds. A
chance of showers after midnight.
.TUE...S winds 10 to 15 kt with gusts up to 20 kt. Seas around
2 ft. Wave Detail: S 2 ft at 3 seconds and N 1 foot at 4 seconds.
Showers likely, mainly in the morning.
.TUE NIGHT...SW winds 10 to 15 kt, becoming NW 5 to 10 kt after
midnight. Seas around 2 ft. Wave Detail: SW 1 foot at 4 seconds
and E 1 foot 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.

$$

ANZ254-210000-
Coastal waters from Provincetown MA to Chatham MA to Nantucket MA
out 20 nm-
705 AM EDT Sun Apr 20 2025

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

.TODAY...NW winds 15 to 20 kt with gusts up to 30 kt. Seas 4 to
6 ft. Wave Detail: S 5 ft at 9 seconds and NW 3 ft at 4 seconds.
.TONIGHT...NW winds 10 to 15 kt with gusts up to 25 kt. Seas 3 to
5 ft. Wave Detail: NW 3 ft at 6 seconds and S 3 ft at 8 seconds.
.MON...N winds 5 to 10 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: S
2 ft at 4 seconds and N 2 ft at 5 seconds. A chance of showers
after midnight.
.TUE...S winds around 15 kt with gusts up to 20 kt. Seas 3 to
5 ft. Wave Detail: S 4 ft at 5 seconds and N 1 foot 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. Wave Detail: SW 4 ft
at 5 seconds and SE 1 foot at 9 seconds.
.WED AND WED NIGHT...W winds 5 to 10 kt, becoming SW. 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.

$$

ANZ255-210000-
Coastal Waters extending out to 25 nm South of Marthas Vineyard
and Nantucket-
705 AM EDT Sun Apr 20 2025

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

.TODAY...W winds 15 to 20 kt, becoming NW 10 to 15 kt this
afternoon. Gusts up to 25 kt. Seas 5 to 7 ft. Wave Detail: SW
7 ft at 8 seconds and NW 1 foot at 4 seconds.
.TONIGHT...NW winds 5 to 10 kt. Seas 3 to 5 ft. Wave Detail: SW
5 ft at 8 seconds and N 1 foot at 4 seconds.
.MON...NE winds 5 to 10 kt, becoming SE in the afternoon. Seas
2 to 3 ft. Wave Detail: S 2 ft at 7 seconds and NW 1 foot at
3 seconds.
.MON NIGHT...S winds around 10 kt, increasing to 15 to 20 kt
after midnight. Seas 2 to 3 ft. Wave Detail: S 3 ft at 4 seconds
and NE 1 foot at 5 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 4 ft at 5 seconds and NE 1 foot 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. Wave Detail: SW 4 ft
at 6 seconds and W 1 foot at 3 seconds.
.WED AND WED NIGHT...W winds 5 to 10 kt, becoming SW. 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.

$$

ANZ256-210000-
Coastal Waters from Montauk NY to Marthas Vineyard extending out
to 20 nm South of Block Island-
705 AM EDT Sun Apr 20 2025

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

.TODAY...NW winds 15 to 20 kt, diminishing to 10 to 15 kt this
afternoon. Gusts up to 25 kt. Seas 5 to 7 ft. Wave Detail: S 6 ft
at 8 seconds and NW 2 ft at 4 seconds.
.TONIGHT...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 5 to 10 kt, becoming S in the afternoon. Seas
2 to 3 ft. Wave Detail: S 2 ft at 7 seconds and N 1 foot at
3 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 4 seconds and SE
1 foot at 9 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: S 4 ft at 5 seconds and SE 1 foot at
9 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. Wave Detail: SW 4 ft
at 6 seconds and SE 1 foot at 9 seconds.
.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.

$$

ANZ232-210000-
Nantucket Sound-
705 AM EDT Sun Apr 20 2025

.TODAY...NW winds 10 to 15 kt with gusts up to 25 kt. Seas 2 to
4 ft. Wave Detail: NW 2 ft at 4 seconds and S 2 ft at 8 seconds.
.TONIGHT...NW winds 5 to 10 kt. Gusts up to 20 kt in the evening.
Seas around 2 ft. Wave Detail: NW 2 ft at 3 seconds and S 2 ft at
8 seconds.
.MON...NE winds 5 to 10 kt, becoming S in the afternoon. Seas
1 foot or less. Wave Detail: NE 1 foot at 3 seconds and NW 1 foot
at 3 seconds.
.MON NIGHT...S winds 10 to 15 kt. Gusts up to 20 kt after
midnight. Seas 1 foot or less, then around 2 ft after midnight.
Wave Detail: S 1 foot at 3 seconds and N 1 foot at 5 seconds,
becoming S 2 ft at 3 seconds and NE 1 foot at 5 seconds. A chance
of showers after midnight.
.TUE...S winds 15 to 20 kt. Seas 2 to 3 ft. Wave Detail: S 3 ft
at 4 seconds and N 1 foot at 5 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 2 ft at 5 seconds and SE 1 foot at 9 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.

$$

ANZ233-210000-
Vineyard Sound-
705 AM EDT Sun Apr 20 2025

.TODAY...NW winds 10 to 15 kt with gusts up to 25 kt. Seas 2 to
4 ft. Wave Detail: S 4 ft at 8 seconds and NW 2 ft at 3 seconds.
.TONIGHT...N winds 5 to 10 kt. Seas around 2 ft. Wave Detail: SW
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: N 1 foot at 4 seconds and SW 1 foot
at 7 seconds.
.MON NIGHT...S winds 10 to 15 kt. Gusts up to 20 kt after
midnight. Seas 1 foot or less, then around 2 ft after midnight.
Wave Detail: S 1 foot at 4 seconds and SE 1 foot at 9 seconds,
becoming S 2 ft at 4 seconds and SE 1 foot at 9 seconds. A chance
of showers after midnight.
.TUE...SW winds 15 to 20 kt. Seas 2 to 3 ft. Wave Detail: S 3 ft
at 5 seconds and SE 1 foot at 9 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 and W 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.

$$

ANZ234-210000-
Buzzards Bay-
705 AM EDT Sun Apr 20 2025

.TODAY...NW winds 10 to 15 kt with gusts up to 25 kt. Seas 2 to
3 ft. Wave Detail: SW 3 ft at 8 seconds and NW 2 ft at 3 seconds.
.TONIGHT...NW winds 5 to 10 kt. Gusts up to 20 kt in the evening.
Seas around 2 ft in the evening, then 1 foot or less. Wave
Detail: SW 2 ft at 8 seconds and NW 1 foot at 3 seconds, becoming
N 1 foot at 4 seconds and SW 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 3 seconds and N 1 foot
at 4 seconds.
.MON NIGHT...S winds 10 to 15 kt. Gusts up to 20 kt after
midnight. Seas 1 foot or less, then around 2 ft after midnight.
Wave Detail: S 1 foot at 3 seconds and NE 1 foot at 5 seconds,
becoming S 2 ft at 3 seconds and NE 1 foot at 5 seconds. A chance
of showers after midnight.
.TUE...SW winds around 15 kt with gusts up to 20 kt. Seas 2 to
3 ft. Wave Detail: SW 3 ft at 5 seconds and NE 1 foot at
5 seconds. Showers likely, mainly in the morning.
.TUE NIGHT...W 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 and W 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.

$$

ANZ235-210000-
Rhode Island Sound-
705 AM EDT Sun Apr 20 2025

...SMALL CRAFT ADVISORY IN EFFECT UNTIL 1 PM EDT THIS AFTERNOON...

.TODAY...NW winds 15 to 20 kt, diminishing to 10 to 15 kt this
afternoon. Gusts up to 25 kt. Seas 3 to 5 ft. Wave Detail: S 5 ft
at 8 seconds and W 2 ft at 5 seconds.
.TONIGHT...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 5 to 10 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 and N 1 foot at 3 seconds, becoming NE 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 and SE
1 foot at 9 seconds. A chance of showers after midnight.
.TUE...SW winds around 15 kt with gusts up to 20 kt. Seas 2 to
4 ft. Wave Detail: S 4 ft at 5 seconds and SE 1 foot at
9 seconds. Showers likely, mainly in the morning.
.TUE NIGHT...SW winds 10 to 15 kt with gusts up to 20 kt,
becoming NW after midnight. Seas 2 to 4 ft. Wave Detail: S 4 ft
at 6 seconds and W 1 foot at 3 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.

$$

ANZ237-210000-
Block Island Sound-
705 AM EDT Sun Apr 20 2025

...SMALL CRAFT ADVISORY IN EFFECT UNTIL 1 PM EDT THIS AFTERNOON...

.TODAY...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 5 seconds.
.TONIGHT...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 and SE
1 foot at 9 seconds. A chance of showers 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 and SE 1 foot at
9 seconds. A chance of showers.
.TUE NIGHT...W winds 10 to 15 kt, becoming NW 5 to 10 kt after
midnight. Seas 2 to 3 ft. Wave Detail: S 3 ft at 6 seconds and W
1 foot at 3 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.

$$

ANZ230-210000-
Boston Harbor-
705 AM EDT Sun Apr 20 2025

...SMALL CRAFT ADVISORY IN EFFECT UNTIL 1 PM EDT THIS AFTERNOON...

.TODAY...NW winds 20 to 25 kt, diminishing to 15 to 20 kt this
afternoon. Gusts up to 30 kt. Waves around 2 ft.
.TONIGHT...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 10 to 15 kt 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...S winds 10 to 15 kt. Waves around 2 ft. Showers likely,
mainly in the morning.
.TUE NIGHT...W winds 10 to 15 kt. Waves around 2 ft in the
evening, then 1 foot or less.
.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.

$$

ANZ236-210000-
Narragansett Bay-
705 AM EDT Sun Apr 20 2025

.TODAY...NW winds 10 to 15 kt with gusts up to 25 kt. Waves 2 to
3 ft.
.TONIGHT...N winds 5 to 10 kt. Gusts up to 20 kt in the evening.
Waves 2 to 3 ft.
.MON...NE winds around 5 kt, becoming S in the afternoon. Waves
1 foot or less.
.MON NIGHT...S winds 10 to 15 kt. Waves 2 to 3 ft. A chance of
showers after midnight.
.TUE...SW winds 10 to 15 kt with gusts up to 20 kt. Waves 2 to
3 ft. A chance of showers.
.TUE NIGHT...W winds around 10 kt, becoming NW after midnight.
Waves 2 to 3 ft.
.WED THROUGH THU 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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