Coastal Waters Forecast
Issued by NWS Boston, MA

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FZUS51 KBOX 210502
CWFBOX

Coastal Waters Forecast for Massachusetts and Rhode Island
National Weather Service Boston/Norton MA
101 AM EDT Sun Apr 21 2024

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

ANZ200-211800-
101 AM EDT Sun Apr 21 2024

.Synopsis for Massachusetts and Rhode Island coastal waters...
A cold front sweeps across the MA and RI waters late this afternoon
and will be accompanied by scattered showers. High pres then returns
and brings dry weather tonight, Sun and Mon, accompanied by westerly
winds and good vsby. The high moves overhead on Tue, then offshore
Wednesday, with low pressure moving across New England. This feature
will be accompanied by showers. Then improving trends Thu as low
pressure exits offshore, followed by high pressure over New England
Friday.

$$

ANZ250-211800-
Coastal waters east of Ipswich Bay and the Stellwagen Bank
National Marine Sanctuary-
101 AM EDT Sun Apr 21 2024

.REST OF TONIGHT...NW winds around 15 kt with gusts up to 25 kt.
Seas 2 to 4 ft. Wave Detail: W 2 ft at 3 seconds and SE 2 ft at
7 seconds.
.SUN...W winds 10 to 15 kt with gusts up to 20 kt, becoming SW in
the afternoon. Seas 2 to 3 ft. Wave Detail: W 2 ft at 3 seconds
and SE 2 ft at 7 seconds.
.SUN NIGHT...W winds 10 to 15 kt with gusts up to 25 kt. Seas
2 to 3 ft. Wave Detail: W 3 ft at 4 seconds and SE 2 ft at
7 seconds.
.MON...NW winds 10 to 15 kt. Gusts up to 20 kt in the morning.
Seas 2 to 4 ft. Wave Detail: W 3 ft at 4 seconds and SE 2 ft at
7 seconds.
.MON NIGHT...SW winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: NW
2 ft at 4 seconds and SE 1 ft at 7 seconds.
.TUE AND TUE NIGHT...S winds 20 to 25 kt with gusts up to 30 kt.
Seas 2 to 4 ft. Wave Detail: NW 2 ft at 3 seconds and SE 2 ft at
7 seconds.
.WED AND WED NIGHT...S winds 15 to 20 kt, becoming W. Gusts up to
30 kt. Seas 3 to 5 ft. A chance of showers.
.THU AND THU NIGHT...W winds 10 to 15 kt with gusts up to 25 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.

$$

ANZ251-211800-
Massachusetts Bay and Ipswich Bay-
101 AM EDT Sun Apr 21 2024

.REST OF TONIGHT...NW winds 10 to 15 kt with gusts up to 20 kt.
Seas around 2 ft. Wave Detail: W 2 ft at 3 seconds and SE 1 ft at
7 seconds.
.SUN...W winds 5 to 10 kt, becoming SW in the afternoon. Seas
around 2 ft. Wave Detail: W 2 ft at 3 seconds and SE 1 ft at
7 seconds.
.SUN NIGHT...W winds 10 to 15 kt with gusts up to 20 kt. Seas
around 2 ft. Wave Detail: W 2 ft at 3 seconds and SE 1 ft at
7 seconds.
.MON...NW winds 10 to 15 kt with gusts up to 20 kt, diminishing
to 5 to 10 kt in the afternoon. Seas around 2 ft. Wave Detail: W
2 ft at 3 seconds and SE 1 ft at 7 seconds.
.MON NIGHT...S winds 5 to 10 kt, becoming SW after midnight. Seas
around 2 ft. Wave Detail: NW 2 ft at 3 seconds and SE 1 ft at
7 seconds.
.TUE AND TUE NIGHT...S winds 20 to 25 kt with gusts up to 30 kt.
Seas 2 to 4 ft. Wave Detail: SE 2 ft at 7 seconds and NW 1 ft at
3 seconds.
.WED AND WED NIGHT...S winds 15 to 20 kt, becoming W. Gusts up to
25 kt. Seas 2 to 4 ft. A chance of showers.
.THU AND THU NIGHT...W winds 10 to 15 kt with gusts up to 25 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.

$$

ANZ231-211800-
Cape Cod Bay-
101 AM EDT Sun Apr 21 2024

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

$$

ANZ254-211800-
Coastal waters from Provincetown MA to Chatham MA to Nantucket MA
out 20 nm-
101 AM EDT Sun Apr 21 2024

.REST OF TONIGHT...NW winds 10 to 15 kt with gusts up to 25 kt.
Seas 3 to 4 ft. Wave Detail: SE 3 ft at 7 seconds and NW 1 ft at
3 seconds.
.SUN...NW winds 10 to 15 kt, becoming SW in the afternoon. Seas
2 to 4 ft. Wave Detail: SE 3 ft at 7 seconds and W 2 ft at
4 seconds.
.SUN NIGHT...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 SE 2 ft at
7 seconds.
.MON...NW winds 10 to 15 kt. Gusts up to 20 kt in the morning.
Seas 2 to 4 ft. Wave Detail: NW 2 ft at 4 seconds and SE 2 ft at
7 seconds.
.MON NIGHT THROUGH TUE NIGHT...S winds 10 to 15 kt with gusts up
to 25 kt. Seas 2 to 3 ft. Wave Detail: NW 2 ft at 4 seconds and
SE 1 ft at 7 seconds.
.WED...S winds 15 to 20 kt with gusts up to 30 kt. Seas 3 to
4 ft. Wave Detail: S 3 ft at 8 seconds and SW 1 ft at 4 seconds.
.WED NIGHT THROUGH THU NIGHT...W winds 15 to 20 kt with gusts up
to 25 kt. Seas 4 to 6 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.

$$

ANZ255-211800-
Coastal Waters extending out to 25 nm South of Marthas Vineyard
and Nantucket-
101 AM EDT Sun Apr 21 2024

.REST OF TONIGHT...NW winds 10 to 15 kt with gusts up to 25 kt.
Seas 2 to 4 ft. Wave Detail: SE 3 ft at 7 seconds and W 1 ft at
3 seconds.
.SUN...NW winds 10 to 15 kt, becoming W with gusts up to 20 kt in
the afternoon. Seas 2 to 4 ft. Wave Detail: SE 3 ft at 7 seconds
and W 2 ft at 4 seconds.
.SUN NIGHT...W winds 10 to 15 kt with gusts up to 20 kt. Seas
2 to 3 ft. Wave Detail: SW 3 ft at 4 seconds and SE 2 ft at
7 seconds.
.MON...NW winds 10 to 15 kt with gusts up to 20 kt, becoming W
5 to 10 kt in the afternoon. Seas 2 to 3 ft. Wave Detail: W 3 ft
at 5 seconds and SE 2 ft at 7 seconds.
.MON NIGHT THROUGH TUE NIGHT...S winds 10 to 15 kt with gusts up
to 20 kt. Seas 2 to 3 ft. Wave Detail: SW 2 ft at 4 seconds and
SE 1 ft at 7 seconds.
.WED...S winds 15 to 20 kt with gusts up to 30 kt. Seas 2 to
4 ft. Wave Detail: S 4 ft at 7 seconds and SW 3 ft at 4 seconds.
.WED NIGHT AND THU...W winds around 15 kt with gusts up to 25 kt.
Seas 4 to 6 ft.
.THU NIGHT...W winds 10 to 15 kt with gusts up to 25 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.

$$

ANZ256-211800-
Coastal Waters from Montauk NY to Marthas Vineyard extending out
to 20 nm South of Block Island-
101 AM EDT Sun Apr 21 2024

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

$$

ANZ232-211800-
Nantucket Sound-
101 AM EDT Sun Apr 21 2024

.REST OF TONIGHT...NW winds 10 to 15 kt with gusts up to 20 kt.
Seas around 2 ft. Wave Detail: W 1 ft at 3 seconds and SE 1 ft at
7 seconds.
.SUN...NW winds 5 to 10 kt, becoming SW 10 to 15 kt with gusts up
to 20 kt in the afternoon. Seas around 2 ft. Wave Detail: W 2 ft
at 3 seconds and SE 1 ft at 7 seconds.
.SUN NIGHT...W winds 10 to 15 kt with gusts up to 20 kt. Seas
around 2 ft. Wave Detail: SW 2 ft at 3 seconds and SE 1 ft at
7 seconds.
.MON...NW winds 10 to 15 kt with gusts up to 20 kt, diminishing
to 5 to 10 kt in the afternoon. Seas around 2 ft in the morning,
then 1 foot or less. Wave Detail: W 2 ft at 3 seconds and SE 1 ft
at 7 seconds, becoming W 1 ft at 3 seconds and SE 1 ft at
7 seconds.
.MON NIGHT THROUGH TUE NIGHT...S winds 10 to 15 kt with gusts up
to 20 kt. Seas around 2 ft. Wave Detail: SW 1 ft at 4 seconds and
SE 1 ft at 7 seconds.
.WED THROUGH THU NIGHT...W winds 15 to 20 kt with gusts up to
30 kt. Seas 2 to 4 ft. Wave Detail: NW 3 ft at 4 seconds and S
2 ft at 4 seconds.

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.

$$

ANZ233-211800-
Vineyard Sound-
101 AM EDT Sun Apr 21 2024

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

$$

ANZ234-211800-
Buzzards Bay-
101 AM EDT Sun Apr 21 2024

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

$$

ANZ235-211800-
Rhode Island Sound-
101 AM EDT Sun Apr 21 2024

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

$$

ANZ237-211800-
Block Island Sound-
101 AM EDT Sun Apr 21 2024

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

$$

ANZ230-211800-
Boston Harbor-
101 AM EDT Sun Apr 21 2024

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

$$

ANZ236-211800-
Narragansett Bay-
101 AM EDT Sun Apr 21 2024

.REST OF TONIGHT...NW winds 5 to 10 kt with gusts up to 20 kt.
Waves around 2 ft.
.SUN...NW winds 5 to 10 kt, becoming SW 10 to 15 kt with gusts up
to 20 kt in the afternoon. Waves around 2 ft.
.SUN NIGHT...W winds 5 to 10 kt. Waves around 2 ft.
.MON...W winds 5 to 10 kt. Waves 1 foot or less.
.MON NIGHT...W winds 5 to 10 kt. Waves 1 foot or less.
.TUE AND TUE NIGHT...S winds 15 to 20 kt with gusts up to 25 kt.
Waves around 2 ft.
.WED AND WED NIGHT...S winds 15 to 20 kt, becoming W 10 to 15 kt.
Gusts up to 30 kt. Waves 2 to 4 ft. A chance of showers.
.THU AND THU NIGHT...W winds 10 to 15 kt with gusts up to 20 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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