Coastal Waters Forecast
Issued by NWS Boston, MA

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FZUS51 KBOX 021704
CWFBOX

Coastal Waters Forecast for Massachusetts and Rhode Island
National Weather Service Boston/Norton MA
104 PM EDT Tue Sep 2 2025

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

ANZ200-030600-
104 PM EDT Tue Sep 2 2025

.Synopsis for Massachusetts and Rhode Island coastal waters...
High pressure will continue to dominate through the middle of next
week before a cold front approaches from the west.Expect dry
conditions and winds less than 25 kts through Thursday, although
seas may start to build tonight into Tuesday to around 4 feet on the
outer waters. Next chance for precipitation comes Friday and
Saturday as the cold front moves through.

$$

ANZ250-030600-
Coastal waters east of Ipswich Bay and the Stellwagen Bank
National Marine Sanctuary-
104 PM EDT Tue Sep 2 2025

.THIS AFTERNOON...SE winds 5 to 10 kt. Seas 2 to 3 ft. Wave
Detail: SE 3 ft at 8 seconds and NE 1 foot at 3 seconds.
.TONIGHT...S winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: SE
3 ft at 8 seconds.
.WED...S winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: SE 3 ft
at 8 seconds.
.WED NIGHT...S winds around 10 kt, becoming SW after midnight.
Seas 2 to 4 ft. Wave Detail: E 3 ft at 8 seconds and S 1 foot at
3 seconds. Patchy fog. Vsby 1 to 3 NM.
.THU AND THU NIGHT...S winds 10 to 15 kt with gusts up to 20 kt.
Seas 2 to 3 ft. Wave Detail: E 3 ft at 8 seconds and S 2 ft at
3 seconds.
.FRI AND FRI NIGHT...S winds 15 to 20 kt with gusts up to 25 kt.
Seas 2 to 4 ft. Wave Detail: S 3 ft at 4 seconds and E 2 ft at
8 seconds.
.SAT AND SAT NIGHT...S winds 10 to 15 kt, becoming SW. Gusts up
to 20 kt. Seas 2 to 4 ft. A chance of showers.

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.

$$

ANZ251-030600-
Massachusetts Bay and Ipswich Bay-
104 PM EDT Tue Sep 2 2025

.THIS AFTERNOON...SE winds 5 to 10 kt. Seas around 2 ft. Wave
Detail: E 2 ft at 8 seconds and NE 1 foot at 3 seconds.
.TONIGHT...S winds 5 to 10 kt, becoming SW after midnight. Seas
2 to 3 ft. Wave Detail: E 3 ft at 8 seconds.
.WED...S winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: E 3 ft at
8 seconds and SE 1 foot at 2 seconds.
.WED NIGHT...S winds 10 to 15 kt, becoming SW 5 to 10 kt after
midnight. Seas 2 to 3 ft. Wave Detail: E 3 ft at 8 seconds and S
1 foot at 3 seconds. Patchy fog after midnight with vsby 1 to
3 NM.
.THU AND THU NIGHT...S winds 10 to 15 kt with gusts up to 20 kt.
Seas 2 to 3 ft. Wave Detail: E 3 ft at 8 seconds and S 2 ft at
3 seconds.
.FRI AND FRI NIGHT...S winds 10 to 15 kt with gusts up to 25 kt.
Seas 2 to 3 ft. Wave Detail: SE 3 ft at 6 seconds and SW 1 foot
at 3 seconds.
.SAT AND SAT NIGHT...S winds 10 to 15 kt, becoming W. Gusts up to
20 kt. Seas 2 to 3 ft. A chance of showers.

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.

$$

ANZ231-030600-
Cape Cod Bay-
104 PM EDT Tue Sep 2 2025

.THIS AFTERNOON...E winds 5 to 10 kt. Seas around 2 ft. Wave
Detail: E 2 ft at 8 seconds and E 1 foot at 2 seconds.
.TONIGHT...SE winds 5 to 10 kt, diminishing to around 5 kt after
midnight. Seas around 2 ft. Wave Detail: E 2 ft at 8 seconds and
E 1 foot at 2 seconds.
.WED...E winds around 5 kt, becoming SE in the afternoon. Seas
around 2 ft. Wave Detail: E 2 ft at 8 seconds and SE 1 foot at
2 seconds.
.WED NIGHT...S winds 5 to 10 kt, becoming SW after midnight. Seas
around 2 ft. Wave Detail: E 2 ft at 8 seconds and S 1 foot at
2 seconds. Patchy fog. Vsby 1 to 3 NM, decreasing to 1 NM or less
after midnight.
.THU AND THU NIGHT...S winds 5 to 10 kt. Seas around 2 ft. Wave
Detail: E 2 ft at 8 seconds.
.FRI AND FRI NIGHT...S winds 10 to 15 kt with gusts up to 25 kt.
Seas 2 to 4 ft. Wave Detail: SW 2 ft at 3 seconds and S 2 ft at
6 seconds.
.SAT AND SAT NIGHT...SW winds 10 to 15 kt with gusts up to 20 kt.
Seas 2 to 3 ft. A chance of showers.

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.

$$

ANZ254-030600-
Coastal waters from Provincetown MA to Chatham MA to Nantucket MA
out 20 nm-
104 PM EDT Tue Sep 2 2025

.THIS AFTERNOON...E winds 5 to 10 kt. Seas 2 to 4 ft. Wave
Detail: SE 3 ft at 8 seconds and N 1 foot at 3 seconds.
.TONIGHT...E winds 5 to 10 kt. Seas 3 to 4 ft. Wave Detail: SE
3 ft at 8 seconds.
.WED...E winds 5 to 10 kt. Seas 3 to 4 ft. Wave Detail: E 3 ft at
8 seconds.
.WED NIGHT...SE winds 5 to 10 kt, becoming S after midnight. Seas
2 to 3 ft. Wave Detail: E 3 ft at 8 seconds.
.THU AND THU NIGHT...S winds 5 to 10 kt. Seas 2 to 3 ft. Wave
Detail: E 3 ft at 8 seconds and S 1 foot at 2 seconds.
.FRI AND FRI NIGHT...S winds 10 to 15 kt with gusts up to 20 kt.
Seas 2 to 4 ft. Wave Detail: S 2 ft at 3 seconds and S 2 ft at
7 seconds.
.SAT AND SAT NIGHT...SW winds 10 to 15 kt with gusts up to 20 kt.
Seas 3 to 4 ft. A chance of showers.

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.

$$

ANZ255-030600-
Coastal Waters extending out to 25 nm South of Marthas Vineyard
and Nantucket-
104 PM EDT Tue Sep 2 2025

.THIS AFTERNOON...E winds around 10 kt. Seas 2 to 4 ft. Wave
Detail: SE 3 ft at 8 seconds.
.TONIGHT...E winds 5 to 10 kt. Seas 2 to 4 ft. Wave Detail: E
3 ft at 8 seconds and NE 1 foot at 3 seconds.
.WED...E winds 5 to 10 kt. Seas 2 to 4 ft. Wave Detail: SE 3 ft
at 8 seconds.
.WED NIGHT...SE winds 5 to 10 kt, becoming S after midnight. Seas
2 to 3 ft. Wave Detail: SE 3 ft at 8 seconds.
.THU AND THU NIGHT...S winds 5 to 10 kt. Seas 2 to 3 ft. Wave
Detail: E 3 ft at 8 seconds and S 2 ft at 3 seconds.
.FRI AND FRI NIGHT...S winds 10 to 15 kt with gusts up to 20 kt.
Seas 2 to 4 ft. Wave Detail: S 4 ft at 7 seconds and S 3 ft at
4 seconds.
.SAT AND SAT NIGHT...SW winds 10 to 15 kt with gusts up to 20 kt.
Seas 3 to 5 ft. A chance of showers.

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.

$$

ANZ256-030600-
Coastal Waters from Montauk NY to Marthas Vineyard extending out
to 20 nm South of Block Island-
104 PM EDT Tue Sep 2 2025

.THIS AFTERNOON...E winds around 10 kt. Seas 3 to 4 ft. Wave
Detail: SE 3 ft at 8 seconds.
.TONIGHT...E winds 5 to 10 kt. Seas 3 to 4 ft. Wave Detail: SE
4 ft at 8 seconds.
.WED...NE winds 5 to 10 kt, becoming E in the afternoon. Seas
2 to 4 ft. Wave Detail: SE 4 ft at 8 seconds.
.WED NIGHT...S winds around 5 kt. Seas 2 to 3 ft. Wave Detail: SE
3 ft at 8 seconds.
.THU AND THU NIGHT...S winds 5 to 10 kt. Seas 2 to 3 ft. Wave
Detail: E 3 ft at 8 seconds and S 2 ft at 4 seconds.
.FRI AND FRI NIGHT...S winds 10 to 15 kt with gusts up to 20 kt.
Seas 3 to 5 ft. Wave Detail: S 4 ft at 7 seconds and S 2 ft at
4 seconds.
.SAT AND SAT NIGHT...SW winds 10 to 15 kt, becoming W. Gusts up
to 20 kt. Seas 3 to 5 ft. A chance of showers.

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.

$$

ANZ232-030600-
Nantucket Sound-
104 PM EDT Tue Sep 2 2025

.THIS AFTERNOON...E winds around 10 kt. Seas around 2 ft. Wave
Detail: E 2 ft at 8 seconds and E 1 foot at 3 seconds.
.TONIGHT...E winds 5 to 10 kt. Seas around 2 ft. Wave Detail: E
2 ft at 8 seconds and NE 1 foot at 3 seconds.
.WED...E winds 5 to 10 kt. Seas around 2 ft. Wave Detail: E 2 ft
at 8 seconds and SE 1 foot at 2 seconds.
.WED NIGHT...SE winds 5 to 10 kt, becoming SW after midnight.
Seas around 2 ft. Wave Detail: E 2 ft at 8 seconds and S 1 foot
at 2 seconds. Patchy fog after midnight.
.THU AND THU NIGHT...S winds 10 to 15 kt. Seas around 2 ft. Wave
Detail: S 2 ft at 3 seconds and S 1 foot at 7 seconds.
.FRI AND FRI NIGHT...S winds 10 to 15 kt with gusts up to 20 kt.
Seas 2 to 3 ft. Wave Detail: SW 2 ft at 3 seconds and S 2 ft at
7 seconds.
.SAT AND SAT NIGHT...SW winds 10 to 15 kt with gusts up to 20 kt.
Seas 2 to 3 ft. A chance of showers.

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.

$$

ANZ233-030600-
Vineyard Sound-
104 PM EDT Tue Sep 2 2025

.THIS AFTERNOON...E winds around 10 kt. Seas around 2 ft. Wave
Detail: SE 2 ft at 8 seconds and E 1 foot at 2 seconds.
.TONIGHT...E winds 5 to 10 kt. Seas around 2 ft. Wave Detail: SE
2 ft at 8 seconds and E 1 foot at 2 seconds.
.WED...NE winds around 5 kt, becoming SE in the afternoon. Seas
around 2 ft in the morning, then 1 foot or less. Wave Detail: SE
1 foot at 8 seconds, becoming S 1 foot at 2 seconds and SE 1 foot
at 8 seconds.
.WED NIGHT...S winds 5 to 10 kt. Seas 1 foot or less. Wave
Detail: S 1 foot at 2 seconds and SE 1 foot at 8 seconds.
.THU AND THU NIGHT...S winds 5 to 10 kt. Seas around 2 ft. Wave
Detail: SW 1 foot at 3 seconds and SE 1 foot at 7 seconds.
.FRI AND FRI NIGHT...S winds 10 to 15 kt with gusts up to 20 kt.
Seas 2 to 4 ft. Wave Detail: S 3 ft at 7 seconds and S 2 ft at
4 seconds.
.SAT AND SAT NIGHT...SW winds 10 to 15 kt with gusts up to 20 kt.
Seas 2 to 3 ft. A chance of showers.

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.

$$

ANZ234-030600-
Buzzards Bay-
104 PM EDT Tue Sep 2 2025

.THIS AFTERNOON...E winds around 10 kt. Seas around 2 ft. Wave
Detail: SE 2 ft at 8 seconds and E 1 foot at 2 seconds.
.TONIGHT...SE winds 5 to 10 kt, becoming E after midnight. Seas
around 2 ft. Wave Detail: SE 2 ft at 8 seconds and E 1 foot at
2 seconds.
.WED...NE winds around 5 kt, becoming SE in the afternoon. Seas
around 2 ft in the morning, then 1 foot or less. Wave Detail: SE
2 ft at 8 seconds, becoming S 1 foot at 2 seconds and SE 1 foot
at 8 seconds.
.WED NIGHT...S winds 5 to 10 kt. Seas 1 foot or less. Wave
Detail: S 1 foot at 2 seconds and SE 1 foot at 7 seconds.
.THU AND THU NIGHT...S winds 5 to 10 kt. Seas around 2 ft. Wave
Detail: S 1 foot at 2 seconds and S 1 foot at 7 seconds.
.FRI AND FRI NIGHT...S winds 10 to 15 kt with gusts up to 25 kt.
Seas 2 to 4 ft. Wave Detail: S 2 ft at 3 seconds and S 2 ft at
7 seconds.
.SAT AND SAT NIGHT...SW winds 10 to 15 kt with gusts up to 20 kt.
Seas 2 to 3 ft. A chance of showers.

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.

$$

ANZ235-030600-
Rhode Island Sound-
104 PM EDT Tue Sep 2 2025

.THIS AFTERNOON...E winds around 10 kt. Seas 2 to 3 ft. Wave
Detail: SE 3 ft at 8 seconds and NE 1 foot at 2 seconds.
.TONIGHT...E winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: SE
3 ft at 8 seconds and NE 1 foot at 2 seconds.
.WED...NE winds around 5 kt, becoming SE in the afternoon. Seas
2 to 3 ft. Wave Detail: SE 3 ft at 8 seconds.
.WED NIGHT...S winds 5 to 10 kt. Seas around 2 ft. Wave Detail:
SE 2 ft at 8 seconds. Patchy fog after midnight with vsby 1 to
3 NM.
.THU AND THU NIGHT...S winds 10 to 15 kt. Seas around 2 ft. Wave
Detail: S 2 ft at 4 seconds and SE 2 ft at 7 seconds.
.FRI...S winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to
3 ft. Wave Detail: S 3 ft at 4 seconds and S 3 ft at 7 seconds.
.FRI NIGHT...S winds 10 to 15 kt with gusts up to 20 kt. Seas
3 to 5 ft.
.SAT AND SAT NIGHT...SW winds 10 to 15 kt, becoming W. Gusts up
to 20 kt. Seas 3 to 4 ft. A chance of showers.

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.

$$

ANZ237-030600-
Block Island Sound-
104 PM EDT Tue Sep 2 2025

.THIS AFTERNOON...E winds around 10 kt. Seas 2 to 3 ft. Wave
Detail: SE 3 ft at 8 seconds and E 1 foot at 3 seconds.
.TONIGHT...E winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: SE
3 ft at 8 seconds and E 1 foot at 3 seconds.
.WED...NE winds around 5 kt, becoming SE in the afternoon. Seas
2 to 3 ft. Wave Detail: SE 3 ft at 8 seconds.
.WED NIGHT...S winds around 5 kt. Seas around 2 ft. Wave Detail:
SE 2 ft at 8 seconds. Patchy fog after midnight with vsby 1 to
3 NM.
.THU AND THU NIGHT...S winds 5 to 10 kt. Seas 2 to 3 ft. Wave
Detail: S 2 ft at 3 seconds and SE 2 ft at 7 seconds.
.FRI...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 2 ft at 8 seconds.
.FRI NIGHT AND SAT...SW winds 10 to 15 kt with gusts up to 20 kt.
Seas 3 to 5 ft. A chance of showers.
.SAT NIGHT...W winds 10 to 15 kt with gusts up to 20 kt. Seas
2 to 4 ft. A chance of showers.

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.

$$

ANZ230-030600-
Boston Harbor-
104 PM EDT Tue Sep 2 2025

.THIS AFTERNOON...E winds 5 to 10 kt. Waves 1 foot or less.
.TONIGHT...SE winds 5 to 10 kt, becoming SW after midnight. Waves
1 foot or less.
.WED...S winds around 5 kt, becoming SE in the afternoon. Waves
1 foot or less.
.WED NIGHT...S winds 5 to 10 kt, becoming SW after midnight.
Waves 1 foot or less.
.THU AND THU NIGHT...S winds 10 to 15 kt with gusts up to 20 kt.
Waves around 2 ft.
.FRI THROUGH SAT NIGHT...W winds 15 to 20 kt with gusts up to
25 kt. Waves around 2 ft. A chance of showers.

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.

$$

ANZ236-030600-
Narragansett Bay-
104 PM EDT Tue Sep 2 2025

.THIS AFTERNOON...SE winds 5 to 10 kt. Waves around 2 ft.
.TONIGHT...SE winds 5 to 10 kt, becoming N after midnight. Waves
around 2 ft.
.WED...NE winds around 5 kt, becoming S in the afternoon. Waves
around 2 ft.
.WED NIGHT...SW winds 5 to 10 kt. Waves around 2 ft. Patchy fog.
Vsby 1 to 3 NM.
.THU AND THU NIGHT...S winds 5 to 10 kt. Waves around 2 ft.
.FRI...S winds 10 to 15 kt with gusts up to 20 kt. Waves 2 to
3 ft.
.FRI NIGHT THROUGH SAT NIGHT...W winds 10 to 15 kt with gusts up
to 20 kt. Waves 2 to 4 ft. A chance of showers.

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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