153
FZUS51 KBOX 022004
CWFBOX

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

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

ANZ200-030900-
404 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.

$$

ANZ250-030900-
Coastal waters east of Ipswich Bay and the Stellwagen Bank
National Marine Sanctuary-
404 PM EDT Tue Sep 2 2025

.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 and SE 1 foot at 2 seconds.
.WED NIGHT...S winds around 10 kt, becoming SW after midnight.
Seas 2 to 4 ft. Wave Detail: SE 3 ft at 8 seconds and S 1 foot at
2 seconds. Patchy fog. Vsby 1 to 3 NM.
.THU...SW winds 5 to 10 kt, becoming S 10 to 15 kt with gusts up
to 20 kt in the afternoon. Seas 2 to 3 ft. Wave Detail: E 3 ft at
8 seconds and S 2 ft at 3 seconds.
.THU NIGHT THROUGH FRI NIGHT...S winds 15 to 20 kt with gusts up
to 25 kt. Seas 2 to 4 ft. Wave Detail: S 4 ft at 5 seconds and E
3 ft at 8 seconds.
.SAT THROUGH SUN...W winds 10 to 15 kt with gusts up to 20 kt.
Seas 2 to 4 ft. Wave Detail: S 4 ft at 5 seconds and SE 2 ft at
9 seconds. A chance of showers.
.SUN NIGHT...W 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.

$$

ANZ251-030900-
Massachusetts Bay and Ipswich Bay-
404 PM EDT Tue Sep 2 2025

.TONIGHT...S winds 5 to 10 kt, becoming SW after midnight. Seas
2 to 3 ft. Wave Detail: E 3 ft at 8 seconds and E 1 foot at
3 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 3 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 SE
1 foot at 3 seconds. Patchy fog after midnight with vsby 1 to
3 NM.
.THU...S 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: E 3 ft
at 8 seconds and SE 2 ft at 4 seconds.
.THU NIGHT THROUGH 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 4 seconds and
SE 3 ft at 7 seconds.
.SAT THROUGH SUN...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 E 1 foot at
9 seconds. A chance of showers.
.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.

$$

ANZ231-030900-
Cape Cod Bay-
404 PM EDT Tue Sep 2 2025

.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 SE 1 foot at
2 seconds. Patchy fog. Vsby 1 to 3 NM, decreasing to 1 NM or less
after midnight.
.THU...S winds 5 to 10 kt. Seas 1 foot or less, then around 2 ft
in the afternoon. Wave Detail: S 1 foot at 2 seconds and E 1 foot
at 8 seconds, becoming E 2 ft at 8 seconds and S 1 foot at
2 seconds.
.THU NIGHT...S winds around 10 kt. Seas around 2 ft. Wave Detail:
E 2 ft at 8 seconds and SW 1 foot at 3 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 3 ft at 4 seconds and E 2 ft at
8 seconds.
.SAT THROUGH SUN...NW winds 10 to 15 kt with gusts up to 20 kt.
Seas 2 to 3 ft. A chance of showers.
.SUN NIGHT...NW 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.

$$

ANZ254-030900-
Coastal waters from Provincetown MA to Chatham MA to Nantucket MA
out 20 nm-
404 PM EDT Tue Sep 2 2025

.TONIGHT...E winds 5 to 10 kt. Seas 3 to 4 ft. Wave Detail: SE
4 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...S winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: E 3 ft at
8 seconds and S 1 foot at 3 seconds.
.THU NIGHT THROUGH FRI NIGHT...S winds 10 to 15 kt with gusts up
to 20 kt. Seas 2 to 4 ft. Wave Detail: SE 4 ft at 7 seconds and S
3 ft at 4 seconds.
.SAT THROUGH SUN NIGHT...NW winds 10 to 15 kt with gusts up to
20 kt. Seas 2 to 4 ft. Wave Detail: S 4 ft at 6 seconds and NW
2 ft at 3 seconds. 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.

$$

ANZ255-030900-
Coastal Waters extending out to 25 nm South of Marthas Vineyard
and Nantucket-
404 PM EDT Tue Sep 2 2025

.TONIGHT...E winds 5 to 10 kt. Seas 2 to 4 ft. Wave Detail: E
4 ft at 8 seconds.
.WED...E winds 5 to 10 kt. Seas 2 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: SE 3 ft at 8 seconds.
.THU...S winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: SE 3 ft
at 8 seconds.
.THU NIGHT THROUGH FRI NIGHT...S winds 10 to 15 kt with gusts up
to 20 kt. Seas 2 to 4 ft. Wave Detail: SW 4 ft at 5 seconds and
SE 3 ft at 8 seconds.
.SAT THROUGH SUN...W winds 10 to 15 kt with gusts up to 20 kt.
Seas 3 to 5 ft. Wave Detail: S 5 ft at 7 seconds and SE 2 ft at
9 seconds. A chance of showers.
.SUN NIGHT...NW winds 5 to 10 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.

$$

ANZ256-030900-
Coastal Waters from Montauk NY to Marthas Vineyard extending out
to 20 nm South of Block Island-
404 PM EDT Tue Sep 2 2025

.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: E 4 ft at 8 seconds.
.WED NIGHT...S winds around 5 kt. Seas 2 to 3 ft. Wave Detail: E
3 ft at 8 seconds.
.THU...S winds 5 to 10 kt. Seas around 2 ft. Wave Detail: SE 2 ft
at 7 seconds and S 1 foot at 3 seconds.
.THU NIGHT AND FRI...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.
.FRI NIGHT...S winds 10 to 15 kt with gusts up to 20 kt. Seas
3 to 5 ft. Wave Detail: S 5 ft at 7 seconds and S 1 foot at
4 seconds.
.SAT THROUGH SUN...NW winds 10 to 15 kt with gusts up to 20 kt.
Seas 3 to 5 ft. A chance of showers.
.SUN NIGHT...NW winds around 10 kt. Seas around 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.

$$

ANZ232-030900-
Nantucket Sound-
404 PM EDT Tue Sep 2 2025

.TONIGHT...E winds 5 to 10 kt. Seas around 2 ft. Wave Detail: E
2 ft at 8 seconds and E 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 NE 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 E 1 foot
at 2 seconds. Patchy fog after midnight.
.THU...S winds 5 to 10 kt. Seas 1 foot or less. Wave Detail: S
1 foot at 3 seconds and E 1 foot at 8 seconds.
.THU NIGHT THROUGH FRI NIGHT...S winds 10 to 15 kt with gusts up
to 20 kt. Seas 2 to 3 ft. Wave Detail: S 3 ft at 5 seconds and E
1 foot at 8 seconds.
.SAT THROUGH SUN NIGHT...NW 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 SW
2 ft at 7 seconds. 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.

$$

ANZ233-030900-
Vineyard Sound-
404 PM EDT Tue Sep 2 2025

.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 SE 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: SE 1 foot at 2 seconds and SE 1 foot at 8 seconds.
.THU...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 NIGHT THROUGH 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 6 seconds and S
2 ft at 4 seconds.
.SAT THROUGH SUN...W winds 10 to 15 kt with gusts up to 20 kt.
Seas 2 to 3 ft. Wave Detail: SW 3 ft at 7 seconds and S 2 ft at
4 seconds. A chance of showers.
.SUN NIGHT...NW 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.

$$

ANZ234-030900-
Buzzards Bay-
404 PM EDT Tue Sep 2 2025

.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 SE 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...S winds 5 to 10 kt. Seas 1 foot or less, then around 2 ft
in the afternoon. Wave Detail: S 1 foot at 2 seconds and SE
1 foot at 8 seconds, becoming S 1 foot at 3 seconds and SE 1 foot
at 7 seconds.
.THU NIGHT...S winds around 10 kt. Seas around 2 ft. Wave Detail:
SW 2 ft at 4 seconds and SE 1 foot 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: S 3 ft at 7 seconds and S 2 ft at
4 seconds.
.SAT THROUGH SUN...W winds 10 to 15 kt with gusts up to 20 kt.
Seas 2 to 3 ft. A chance of showers.
.SUN NIGHT...NW 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.

$$

ANZ235-030900-
Rhode Island Sound-
404 PM EDT Tue Sep 2 2025

.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 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...S winds 5 to 10 kt. Seas around 2 ft. Wave Detail: S 2 ft
at 3 seconds and SE 2 ft at 7 seconds.
.THU NIGHT AND 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. Wave Detail: S 5 ft at 6 seconds.
.SAT THROUGH SUN...W winds 10 to 15 kt with gusts up to 20 kt.
Seas 2 to 4 ft. A chance of showers.
.SUN NIGHT...NW winds around 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.

$$

ANZ237-030900-
Block Island Sound-
404 PM EDT Tue Sep 2 2025

.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...S winds 5 to 10 kt. Seas around 2 ft. Wave Detail: S 2 ft
at 3 seconds and SE 2 ft at 7 seconds.
.THU NIGHT AND FRI...S winds 10 to 15 kt with gusts up to 20 kt.
Seas 2 to 3 ft. Wave Detail: S 3 ft at 7 seconds and S 2 ft at
4 seconds.
.FRI NIGHT...S winds 10 to 15 kt with gusts up to 20 kt. Seas
3 to 5 ft. Wave Detail: SW 5 ft at 5 seconds and SE 2 ft at
8 seconds. A chance of showers after midnight.
.SAT THROUGH SUN...NW winds 10 to 15 kt with gusts up to 20 kt.
Seas 2 to 4 ft. A chance of showers.
.SUN NIGHT...NW 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.

$$

ANZ230-030900-
Boston Harbor-
404 PM EDT Tue Sep 2 2025

.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...S winds 5 to 10 kt, increasing to 10 to 15 kt with gusts
up to 20 kt in the afternoon. Waves 1 foot or less, then around
2 ft in the afternoon.
.THU NIGHT...S winds 10 to 15 kt. Gusts up to 20 kt in the
evening. Waves around 2 ft in the evening, then 1 foot or less.
.FRI AND FRI NIGHT...S winds 15 to 20 kt with gusts up to 25 kt.
Waves around 2 ft. A chance of showers through the day. A chance
of showers after midnight.
.SAT THROUGH SUN...W winds 10 to 15 kt with gusts up to 20 kt.
Waves around 2 ft. A chance of showers.
.SUN NIGHT...W 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.

$$

ANZ236-030900-
Narragansett Bay-
404 PM EDT Tue Sep 2 2025

.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...S winds 5 to 10 kt. Waves around 2 ft.
.THU NIGHT AND FRI...S winds 10 to 15 kt with gusts up to 20 kt.
Waves 2 to 3 ft.
.FRI NIGHT...S winds 10 to 15 kt. Gusts up to 20 kt in the
evening. Waves 2 to 4 ft. A chance of showers after midnight.
.SAT THROUGH SUN...W winds 10 to 15 kt with gusts up to 20 kt.
Waves 2 to 4 ft. A chance of showers.
.SUN NIGHT...NW 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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