318
FZUS51 KBOX 312004
CWFBOX

Coastal Waters Forecast for Massachusetts and Rhode Island
National Weather Service Boston/Norton MA
404 PM EDT Thu Jul 31 2025

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

ANZ200-010900-
404 PM EDT Thu Jul 31 2025

.Synopsis for Massachusetts and Rhode Island coastal waters...
Low pressure tracks along a front south of New England tonight into
Friday, then out to sea Friday night. A sprawling high pressure
builds across New England this weekend, with winds beginning to
slacken Saturday afternoon. High pressure and tranquil marine
weather lingers into early next week.

$$

ANZ250-010900-
Coastal waters east of Ipswich Bay and the Stellwagen Bank
National Marine Sanctuary-
404 PM EDT Thu Jul 31 2025

...SMALL CRAFT ADVISORY IN EFFECT FROM 8 PM EDT THIS EVENING
THROUGH SATURDAY MORNING...

.TONIGHT...NE winds 15 to 20 kt with gusts up to 30 kt. Seas 2 to
4 ft. Wave Detail: NE 4 ft at 5 seconds and SE 1 foot at
9 seconds. Showers likely with isolated tstms. Vsby 1 to 3 NM.
.FRI...NE winds 15 to 20 kt with gusts up to 30 kt. Seas 3 to
5 ft. Wave Detail: NE 5 ft at 6 seconds and SE 2 ft at 9 seconds.
A chance of showers in the morning with vsby 1 to 3 NM.
.FRI NIGHT...NE winds around 15 kt with gusts up to 25 kt. Seas
4 to 5 ft. Wave Detail: NE 4 ft at 6 seconds and SE 1 foot at
9 seconds.
.SAT...N winds 10 to 15 kt with gusts up to 20 kt, becoming NE
5 to 10 kt in the afternoon. Seas 3 to 4 ft. Wave Detail: E 4 ft
at 7 seconds and N 1 foot at 3 seconds.
.SAT NIGHT...S winds 5 to 10 kt, becoming SW after midnight. Seas
around 3 ft. Wave Detail: E 3 ft at 8 seconds and NE 1 foot at
3 seconds.
.SUN AND SUN NIGHT...SW 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 3 ft at
8 seconds.
.MON THROUGH TUE NIGHT...S winds 10 to 15 kt with gusts up to
20 kt. Seas 2 to 3 ft.

Winds and seas higher in and near tstms.

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.

$$

ANZ251-010900-
Massachusetts Bay and Ipswich Bay-
404 PM EDT Thu Jul 31 2025

...SMALL CRAFT ADVISORY IN EFFECT FROM 2 AM EDT FRIDAY THROUGH
FRIDAY EVENING...

.TONIGHT...NE winds 15 to 20 kt with gusts up to 25 kt. Seas 2 to
3 ft. Wave Detail: NE 3 ft at 5 seconds and E 1 foot at
9 seconds. Showers with isolated tstms. Vsby 1 to 3 NM.
.FRI...NE winds 15 to 20 kt with gusts up to 25 kt. Seas 3 to
4 ft. Wave Detail: NE 4 ft at 6 seconds and E 1 foot at
10 seconds. A chance of showers in the morning with vsby 1 to
3 NM.
.FRI NIGHT...NE winds 10 to 15 kt with gusts up to 25 kt. Seas
2 to 4 ft. Wave Detail: E 4 ft at 6 seconds and SE 1 foot at
9 seconds.
.SAT...N winds 10 to 15 kt with gusts up to 20 kt, becoming E
5 to 10 kt in the afternoon. Seas 2 to 3 ft. Wave Detail: E 3 ft
at 7 seconds.
.SAT NIGHT...S winds around 10 kt, becoming SW after midnight.
Seas 2 to 3 ft. Wave Detail: E 3 ft at 7 seconds and S 1 foot at
2 seconds.
.SUN AND SUN NIGHT...SW 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
4 seconds.
.MON THROUGH TUE NIGHT...S winds 10 to 15 kt with gusts up to
20 kt. Seas around 2 ft.

Winds and seas higher in and near tstms.

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.

$$

ANZ231-010900-
Cape Cod Bay-
404 PM EDT Thu Jul 31 2025

...SMALL CRAFT ADVISORY IN EFFECT FROM 8 PM EDT THIS EVENING
THROUGH LATE FRIDAY NIGHT...

.TONIGHT...NE winds 15 to 20 kt. Gusts up to 20 kt, increasing to
30 kt after midnight. Seas 2 to 4 ft. Wave Detail: N 4 ft at
4 seconds and SE 1 foot at 9 seconds. A chance of showers this
evening, then showers with isolated tstms after midnight with
vsby 1 to 3 NM.
.FRI...NE winds 15 to 20 kt with gusts up to 30 kt. Seas 3 to
4 ft. Wave Detail: N 4 ft at 5 seconds and SE 1 foot at
9 seconds. Patchy fog in the morning. Showers in the morning with
vsby 1 to 3 NM.
.FRI NIGHT...NE winds 15 to 20 kt with gusts up to 25 kt. Seas
2 to 4 ft. Wave Detail: N 4 ft at 4 seconds and SE 1 foot at
9 seconds.
.SAT...N winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to
3 ft. Wave Detail: N 3 ft at 4 seconds and E 3 ft at 7 seconds.
.SAT NIGHT...SE winds 5 to 10 kt, becoming SW after midnight.
Seas around 2 ft. Wave Detail: E 2 ft at 7 seconds and N 1 foot
at 4 seconds.
.SUN AND SUN NIGHT...SW winds 10 to 15 kt with gusts up to 20 kt.
Seas around 2 ft. Wave Detail: E 2 ft at 8 seconds and SW 1 foot
at 2 seconds.
.MON THROUGH TUE NIGHT...SE winds 5 to 10 kt. Seas around 2 ft.

Winds and seas higher in and near tstms.

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.

$$

ANZ254-010900-
Coastal waters from Provincetown MA to Chatham MA to Nantucket MA
out 20 nm-
404 PM EDT Thu Jul 31 2025

...SMALL CRAFT ADVISORY IN EFFECT FROM 8 PM EDT THIS EVENING
THROUGH SATURDAY MORNING...

.TONIGHT...NE winds 10 to 15 kt, increasing to 15 to 20 kt after
midnight. Gusts up to 25 kt. Seas 2 to 4 ft. Wave Detail: NE 4 ft
at 5 seconds and S 1 foot at 4 seconds. A slight chance of
showers this evening, then showers likely with isolated tstms
after midnight. Vsby 1 NM or less, increasing to 1 to 3 NM after
midnight.
.FRI...NE winds 15 to 20 kt with gusts up to 30 kt. Seas 3 to
5 ft. Wave Detail: NE 5 ft at 5 seconds and SE 1 foot at
9 seconds. Patchy fog. Showers likely, mainly in the morning.
Vsby 1 NM or less, increasing to 1 to 3 NM in the afternoon.
.FRI NIGHT...NE winds 15 to 20 kt with gusts up to 25 kt. Seas
4 to 5 ft. Wave Detail: NE 5 ft at 6 seconds and SE 1 foot at
9 seconds.
.SAT...N winds 15 to 20 kt, diminishing to 10 to 15 kt in the
afternoon. Gusts up to 25 kt. Seas 3 to 5 ft. Wave Detail: NE
5 ft at 7 seconds.
.SAT NIGHT...E winds 5 to 10 kt, becoming W after midnight. Seas
3 to 4 ft. Wave Detail: E 4 ft at 7 seconds and NE 1 foot at
3 seconds.
.SUN AND SUN NIGHT...SW winds 5 to 10 kt with gusts up to 20 kt.
Seas 2 to 3 ft. Wave Detail: E 3 ft at 8 seconds and SW 1 foot at
3 seconds.
.MON THROUGH TUE NIGHT...SE winds 5 to 10 kt. Seas 2 to 3 ft.

Winds and seas higher in and near tstms.

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.

$$

ANZ255-010900-
Coastal Waters extending out to 25 nm South of Marthas Vineyard
and Nantucket-
404 PM EDT Thu Jul 31 2025

...SMALL CRAFT ADVISORY IN EFFECT FROM 8 PM EDT THIS EVENING
THROUGH SATURDAY MORNING...

.TONIGHT...NE winds 15 to 20 kt, increasing to 20 to 25 kt after
midnight. Seas 2 to 4 ft. Wave Detail: NE 4 ft at 4 seconds and
SW 1 foot at 4 seconds. A slight chance of showers this evening,
then a chance of showers with isolated tstms after midnight. Vsby
1 NM or less, increasing to 1 to 3 NM after midnight.
.FRI...NE winds 20 to 25 kt with gusts up to 30 kt. Seas 3 to
5 ft. Wave Detail: NE 5 ft at 5 seconds and SE 1 foot at
9 seconds. Patchy fog. Showers likely, mainly in the morning.
Vsby 1 NM or less, increasing to 1 to 3 NM in the afternoon.
.FRI NIGHT...NE winds 20 to 25 kt with gusts up to 30 kt. Seas
4 to 5 ft. Wave Detail: N 5 ft at 5 seconds and SE 1 foot at
9 seconds.
.SAT...NE winds 15 to 20 kt with gusts up to 25 kt. Seas 3 to
5 ft. Wave Detail: N 4 ft at 5 seconds and E 3 ft at 8 seconds.
.SAT NIGHT...E winds 5 to 10 kt, becoming W after midnight. Seas
2 to 4 ft. Wave Detail: E 4 ft at 7 seconds and N 2 ft at
4 seconds.
.SUN AND SUN NIGHT...SW winds 5 to 10 kt. Seas 2 to 3 ft. Wave
Detail: E 3 ft at 8 seconds and SW 1 foot at 2 seconds.
.MON THROUGH TUE NIGHT...E winds 5 to 10 kt. Seas 2 to 3 ft.

Winds and seas higher in and near tstms.

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.

$$

ANZ256-010900-
Coastal Waters from Montauk NY to Marthas Vineyard extending out
to 20 nm South of Block Island-
404 PM EDT Thu Jul 31 2025

...SMALL CRAFT ADVISORY IN EFFECT FROM 8 PM EDT THIS EVENING
THROUGH SATURDAY MORNING...

.TONIGHT...NE winds 15 to 20 kt, increasing to 20 to 25 kt after
midnight. Gusts up to 30 kt. Seas 3 to 5 ft. Wave Detail: NE 5 ft
at 5 seconds and SW 1 foot at 4 seconds. A chance of showers this
evening, then showers with a slight chance of tstms after
midnight. Vsby 1 to 3 NM.
.FRI...NE winds 20 to 25 kt with gusts up to 30 kt. Seas 4 to
6 ft. Wave Detail: NE 6 ft at 6 seconds and SE 1 foot at
9 seconds. Patchy fog. Showers likely in the morning. A chance of
showers in the afternoon. Vsby 1 to 3 NM.
.FRI NIGHT...NE winds 20 to 25 kt with gusts up to 30 kt. Seas
4 to 6 ft. Wave Detail: N 6 ft at 5 seconds and SE 1 foot at
8 seconds.
.SAT...NE 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: N 5 ft
at 5 seconds and SE 1 foot at 8 seconds.
.SAT NIGHT THROUGH SUN NIGHT...SW winds 5 to 10 kt. Seas 2 to
4 ft. Wave Detail: E 3 ft at 8 seconds.
.MON THROUGH TUE NIGHT...E winds 10 to 15 kt. Seas 2 to 3 ft.
Wave Detail: SE 3 ft at 8 seconds and SW 1 foot at 3 seconds.

Winds and seas higher in and near tstms.

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.

$$

ANZ232-010900-
Nantucket Sound-
404 PM EDT Thu Jul 31 2025

...SMALL CRAFT ADVISORY IN EFFECT FROM 8 PM EDT THIS EVENING
THROUGH LATE FRIDAY NIGHT...

.TONIGHT...NE winds 15 to 20 kt, increasing to 20 to 25 kt after
midnight. Seas 2 to 3 ft. Wave Detail: NE 3 ft at 4 seconds and
SW 1 foot at 4 seconds. A chance of showers this evening, then
showers likely with isolated tstms after midnight with vsby 1 to
3 NM.
.FRI...NE winds 20 to 25 kt with gusts up to 30 kt. Seas around
3 ft. Wave Detail: NE 3 ft at 4 seconds and SE 1 foot at
9 seconds. Patchy fog. Showers, mainly in the morning. Vsby 1 NM
or less, increasing to 1 to 3 NM in the afternoon.
.FRI NIGHT...NE winds 15 to 20 kt with gusts up to 25 kt. Seas
around 3 ft. Wave Detail: N 3 ft at 4 seconds and SE 1 foot at
9 seconds.
.SAT...N winds 15 to 20 kt, becoming NE 10 to 15 kt in the
afternoon. Gusts up to 25 kt. Seas 2 to 3 ft. Wave Detail: N 3 ft
at 4 seconds and E 2 ft at 8 seconds.
.SAT NIGHT THROUGH SUN NIGHT...SW winds 5 to 10 kt. Seas 2 to
3 ft. Wave Detail: E 2 ft at 7 seconds and N 1 foot at 4 seconds.
.MON THROUGH TUE NIGHT...SE winds 10 to 15 kt. Seas around 2 ft.
Wave Detail: E 2 ft at 7 seconds and SW 1 foot at 3 seconds.

Winds and seas higher in and near tstms.

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.

$$

ANZ233-010900-
Vineyard Sound-
404 PM EDT Thu Jul 31 2025

...SMALL CRAFT ADVISORY IN EFFECT FROM 8 PM EDT THIS EVENING
THROUGH LATE FRIDAY NIGHT...

.TONIGHT...NE winds 15 to 20 kt, increasing to 20 to 25 kt after
midnight. Seas 2 to 4 ft. Wave Detail: NE 3 ft at 4 seconds and
SW 1 foot at 4 seconds. A chance of showers this evening, then
showers with a slight chance of tstms after midnight with vsby
1 to 3 NM.
.FRI...NE winds 20 to 25 kt with gusts up to 30 kt. Seas 3 to
4 ft. Wave Detail: NE 3 ft at 4 seconds and SE 1 foot at
9 seconds. Patchy fog. Showers in the morning. A chance of
showers in the afternoon. Vsby 1 to 3 NM.
.FRI NIGHT...NE winds 15 to 20 kt with gusts up to 25 kt. Seas
2 to 4 ft. Wave Detail: N 3 ft at 5 seconds and SE 1 foot at
9 seconds.
.SAT...N winds 15 to 20 kt, becoming NE 10 to 15 kt in the
afternoon. Seas 2 to 3 ft. Wave Detail: N 2 ft at 4 seconds and
SE 1 foot at 8 seconds.
.SAT NIGHT THROUGH SUN NIGHT...SW winds 5 to 10 kt. Seas around
2 ft. Wave Detail: E 1 foot at 3 seconds and SE 1 foot at
7 seconds.
.MON THROUGH TUE NIGHT...SE winds 5 to 10 kt. Seas around 2 ft.
Wave Detail: SE 2 ft at 8 seconds and E 1 foot at 3 seconds.

Winds and seas higher in and near tstms.

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.

$$

ANZ234-010900-
Buzzards Bay-
404 PM EDT Thu Jul 31 2025

...SMALL CRAFT ADVISORY IN EFFECT FROM 8 PM EDT THIS EVENING
THROUGH LATE FRIDAY NIGHT...

.TONIGHT...NE winds 15 to 20 kt with gusts up to 25 kt. Seas 2 to
4 ft. Wave Detail: NE 3 ft at 4 seconds and SW 1 foot at
4 seconds. A chance of showers this evening, then showers with a
slight chance of tstms after midnight with vsby 1 to 3 NM.
.FRI...NE winds around 20 kt with gusts up to 30 kt. Seas 3 to
4 ft. Wave Detail: NE 3 ft at 4 seconds and SE 1 foot at
9 seconds. Patchy fog in the morning. Showers in the morning.
Vsby 1 to 3 NM.
.FRI NIGHT...N winds 15 to 20 kt with gusts up to 25 kt. Seas
2 to 4 ft. Wave Detail: N 3 ft at 4 seconds and SE 1 foot at
8 seconds.
.SAT...NE winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to
3 ft. Wave Detail: N 2 ft at 4 seconds and SE 1 foot at
8 seconds.
.SAT NIGHT THROUGH SUN NIGHT...SW winds 10 to 15 kt. Seas around
2 ft. Wave Detail: E 1 foot at 3 seconds and SE 1 foot at
7 seconds.
.MON THROUGH TUE NIGHT...SE winds 10 to 15 kt. Seas around 2 ft.
Wave Detail: SE 2 ft at 8 seconds and E 1 foot at 3 seconds.

Winds and seas higher in and near tstms.

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.

$$

ANZ235-010900-
Rhode Island Sound-
404 PM EDT Thu Jul 31 2025

...SMALL CRAFT ADVISORY IN EFFECT FROM 8 PM EDT THIS EVENING
THROUGH LATE FRIDAY NIGHT...

.TONIGHT...NE winds 15 to 20 kt, increasing to 20 to 25 kt after
midnight. Seas 2 to 4 ft. Wave Detail: NE 4 ft at 5 seconds and
SW 1 foot at 4 seconds. A chance of showers this evening, then
showers with a slight chance of tstms after midnight with vsby
1 to 3 NM.
.FRI...NE winds 20 to 25 kt with gusts up to 30 kt. Seas 3 to
4 ft. Wave Detail: NE 4 ft at 5 seconds and SE 1 foot at
9 seconds. Patchy fog in the morning. Showers likely in the
morning. Vsby 1 to 3 NM.
.FRI NIGHT...N winds 15 to 20 kt with gusts up to 25 kt. Seas
2 to 4 ft. Wave Detail: N 4 ft at 5 seconds and SE 1 foot at
9 seconds.
.SAT...N winds 15 to 20 kt, becoming NE 10 to 15 kt in the
afternoon. Seas 2 to 4 ft. Wave Detail: N 3 ft at 4 seconds and
SE 1 foot at 8 seconds.
.SAT NIGHT THROUGH SUN NIGHT...SW winds 5 to 10 kt. Seas 2 to
3 ft. Wave Detail: SE 2 ft at 8 seconds and SE 1 foot at
3 seconds.
.MON THROUGH TUE NIGHT...SE winds 5 to 10 kt. Seas around 2 ft.
Wave Detail: SE 2 ft at 8 seconds and SW 1 foot at 3 seconds.

Winds and seas higher in and near tstms.

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.

$$

ANZ237-010900-
Block Island Sound-
404 PM EDT Thu Jul 31 2025

...SMALL CRAFT ADVISORY IN EFFECT FROM 8 PM EDT THIS EVENING
THROUGH LATE FRIDAY NIGHT...

.TONIGHT...NE winds 15 to 20 kt, increasing to 20 to 25 kt after
midnight. Gusts up to 30 kt. Seas 3 to 4 ft. Wave Detail: NE 4 ft
at 5 seconds and S 1 foot at 4 seconds. A slight chance of tstms.
A chance of showers this evening, then showers after midnight.
Vsby 1 to 3 NM.
.FRI...NE winds 20 to 25 kt with gusts up to 30 kt. Seas 3 to
4 ft. Wave Detail: NE 4 ft at 5 seconds and SE 1 foot at
9 seconds. Patchy fog in the morning. Showers likely in the
morning. Vsby 1 to 3 NM.
.FRI NIGHT...NE winds 15 to 20 kt with gusts up to 25 kt. Seas
2 to 4 ft. Wave Detail: E 4 ft at 7 seconds.
.SAT...N winds 10 to 15 kt with gusts up to 20 kt, becoming E in
the afternoon. Seas 2 to 4 ft. Wave Detail: N 3 ft at 4 seconds
and SE 1 foot at 8 seconds.
.SAT NIGHT THROUGH SUN NIGHT...SW winds 5 to 10 kt. Seas 2 to
3 ft. Wave Detail: SE 2 ft at 8 seconds and SE 1 foot at
2 seconds.
.MON THROUGH TUE NIGHT...SE winds 5 to 10 kt. Seas around 2 ft.
Wave Detail: SE 2 ft at 8 seconds and SW 1 foot at 3 seconds.

Winds and seas higher in and near tstms.

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.

$$

ANZ230-010900-
Boston Harbor-
404 PM EDT Thu Jul 31 2025

.TONIGHT...NE winds 15 to 20 kt with gusts up to 25 kt. Waves
2 to 3 ft. A slight chance of tstms. Showers likely this evening,
then showers after midnight. Patchy fog this evening. Vsby 1 to
3 NM.
.FRI...NE winds 15 to 20 kt with gusts up to 25 kt. Waves 2 to
3 ft. Patchy fog in the morning. A chance of showers in the
morning with vsby 1 to 3 NM.
.FRI NIGHT...NE winds 10 to 15 kt with gusts up to 20 kt,
becoming N after midnight. Waves 2 to 3 ft in the evening, then
1 foot or less.
.SAT...N winds 5 to 10 kt, becoming E in the afternoon. Waves
1 foot or less.
.SAT NIGHT...S winds 5 to 10 kt, becoming SW after midnight.
Waves 1 foot or less.
.SUN AND SUN NIGHT...SW winds 10 to 15 kt. Waves around 2 ft.
.MON THROUGH TUE NIGHT...S winds 5 to 10 kt. Waves around 2 ft.

Winds and waves higher in and near tstms.

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.

$$

ANZ236-010900-
Narragansett Bay-
404 PM EDT Thu Jul 31 2025

...SMALL CRAFT ADVISORY IN EFFECT FROM 2 AM EDT FRIDAY THROUGH
FRIDAY EVENING...

.TONIGHT...NE winds 15 to 20 kt with gusts up to 25 kt. Waves
2 to 3 ft. Isolated tstms. A chance of showers this evening, then
showers after midnight with vsby 1 to 3 NM.
.FRI...NE winds 15 to 20 kt with gusts up to 25 kt. Waves around
3 ft. Patchy fog in the morning. Showers likely in the morning
with vsby 1 to 3 NM.
.FRI NIGHT...N winds 10 to 15 kt. Gusts up to 25 kt in the
evening. Waves 2 to 3 ft.
.SAT...N winds around 10 kt, becoming NE in the afternoon. Waves
around 2 ft.
.SAT NIGHT THROUGH SUN NIGHT...SW winds 5 to 10 kt. Waves around
2 ft.
.MON THROUGH TUE NIGHT...SE winds 5 to 10 kt. Waves around 2 ft.

Winds and waves higher in and near tstms.

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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