Coastal Waters Forecast
Issued by NWS Boston, MA

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FZUS51 KBOX 200804
CWFBOX

Coastal Waters Forecast for Massachusetts and Rhode Island
National Weather Service Boston/Norton MA
404 AM EDT Wed Aug 20 2025

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

ANZ200-202100-
404 AM EDT Wed Aug 20 2025

.Synopsis for Massachusetts and Rhode Island coastal waters...
High pres over Quebec gradually shifts east into the Maritimes this
week. All mariners are urged to closely follow the National
Hurricane Center Forecasts for the impacts of Major Hurricane
Erin...especially those with interests in the Atlantic. Although the
Major Hurricane will be passing well to the east of our waters later
this week...high seas are expected to enter our open waters from
large southerly swell.

$$

ANZ250-202100-
Coastal waters east of Ipswich Bay and the Stellwagen Bank
National Marine Sanctuary-
404 AM EDT Wed Aug 20 2025

.TODAY...E winds 5 to 10 kt. Gusts up to 20 kt this afternoon.
Seas 2 to 3 ft. Wave Detail: E 2 ft at 7 seconds and SE 2 ft at
15 seconds. A slight chance of showers this morning, then a
chance of showers this afternoon.
.TONIGHT...E winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to
4 ft. Wave Detail: E 3 ft at 5 seconds and SE 2 ft at 15 seconds.
A chance of showers.
.THU...E winds 15 to 20 kt with gusts up to 30 kt. Seas 3 to
5 ft. Wave Detail: E 5 ft at 6 seconds and SE 2 ft at 15 seconds.
.THU NIGHT...NE winds 20 to 25 kt with gusts up to 35 kt. Seas
5 to 7 ft. Wave Detail: E 7 ft at 8 seconds and SE 2 ft at
8 seconds.
.FRI...NE winds 20 to 25 kt with gusts up to 40 kt. Seas 6 to
9 ft, building to 8 to 11 ft in the afternoon. Wave Detail: NE
9 ft at 8 seconds and SE 3 ft at 19 seconds, becoming NE 11 ft at
9 seconds and SE 6 ft at 19 seconds.
.FRI NIGHT...NE winds 15 to 20 kt, becoming NW after midnight.
Gusts up to 35 kt. Seas 8 to 11 ft. Wave Detail: NE 10 ft at
10 seconds and SE 10 ft at 15 seconds.
.SAT...NE winds 15 to 20 kt with gusts up to 30 kt. Seas 6 to
9 ft.
.SAT NIGHT...S winds 10 to 15 kt with gusts up to 25 kt. Seas
5 to 7 ft.
.SUN...S winds 15 to 20 kt with gusts up to 25 kt. Seas 4 to
5 ft.
.SUN NIGHT...S winds 15 to 20 kt with gusts up to 25 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.

$$

ANZ251-202100-
Massachusetts Bay and Ipswich Bay-
404 AM EDT Wed Aug 20 2025

.TODAY...E winds 5 to 10 kt, increasing to 10 to 15 kt with gusts
up to 20 kt this afternoon. Seas around 2 ft. Wave Detail: E 2 ft
at 6 seconds and SE 2 ft at 17 seconds. A slight chance of
showers this morning, then a chance of showers this afternoon.
.TONIGHT...E winds 10 to 15 kt with gusts up to 20 kt. Seas
around 2 ft. Wave Detail: E 2 ft at 5 seconds and S 2 ft at
17 seconds. Showers likely, mainly in the evening. Patchy fog in
the evening with vsby 1 to 3 NM.
.THU...NE winds 15 to 20 kt with gusts up to 25 kt. Seas 2 to
3 ft. Wave Detail: E 3 ft at 5 seconds and S 2 ft at 15 seconds.
.THU NIGHT...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: E
4 ft at 7 seconds and S 2 ft at 17 seconds.
.FRI...NE winds 20 to 25 kt with gusts up to 35 kt. Seas 5 to
7 ft. Wave Detail: E 7 ft at 9 seconds and SE 2 ft at 20 seconds.
.FRI NIGHT...NE winds 15 to 20 kt, becoming NW after midnight.
Gusts up to 30 kt. Seas 5 to 7 ft. Wave Detail: E 7 ft at
10 seconds and SE 4 ft at 16 seconds.
.SAT...NE winds 15 to 20 kt with gusts up to 25 kt. Seas 5 to
7 ft.
.SAT NIGHT...S winds 10 to 15 kt with gusts up to 20 kt. Seas
4 to 6 ft.
.SUN...S winds 15 to 20 kt with gusts up to 25 kt. Seas 3 to
4 ft.
.SUN NIGHT...S winds 10 to 15 kt with gusts up to 25 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.

$$

ANZ231-202100-
Cape Cod Bay-
404 AM EDT Wed Aug 20 2025

...GALE WATCH IN EFFECT FROM THURSDAY MORNING THROUGH LATE FRIDAY
NIGHT...

.TODAY...E winds 5 to 10 kt, increasing to 10 to 15 kt with gusts
up to 20 kt this afternoon. Seas 2 to 3 ft. Wave Detail: E 2 ft
at 3 seconds and S 2 ft at 14 seconds. A chance of showers this
afternoon.
.TONIGHT...E winds around 15 kt with gusts up to 20 kt. Seas 2 to
3 ft. Wave Detail: SE 2 ft at 3 seconds and S 2 ft at 15 seconds.
Patchy fog. Showers likely, mainly in the evening. Vsby 1 to
3 NM.
.THU...NE winds 15 to 20 kt with gusts up to 30 kt. Seas 3 to
4 ft. Wave Detail: E 3 ft at 4 seconds and S 3 ft at 16 seconds.
A chance of showers in the morning.
.THU NIGHT...NE winds 20 to 25 kt, increasing to 25 to 30 kt
after midnight. Seas 4 to 6 ft. Wave Detail: NE 5 ft at 5 seconds
and S 4 ft at 18 seconds.
.FRI AND FRI NIGHT...N winds 25 to 30 kt with gusts up to 40 kt.
Seas 4 to 6 ft. Wave Detail: N 6 ft at 5 seconds and S 4 ft at
18 seconds.
.SAT...N winds 15 to 20 kt with gusts up to 30 kt. Seas 3 to
5 ft. Wave Detail: NE 5 ft at 9 seconds and NW 3 ft at 5 seconds.
.SAT NIGHT AND SUN...S winds 10 to 15 kt with gusts up to 25 kt.
Seas 2 to 4 ft.
.SUN NIGHT...S 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.

$$

ANZ254-202100-
Coastal waters from Provincetown MA to Chatham MA to Nantucket MA
out 20 nm-
404 AM EDT Wed Aug 20 2025

...SMALL CRAFT ADVISORY IN EFFECT THROUGH THURSDAY MORNING...
...GALE WATCH IN EFFECT FROM THURSDAY MORNING THROUGH LATE FRIDAY
NIGHT...

.TODAY...E winds 10 to 15 kt. Gusts up to 20 kt this afternoon.
Seas 4 to 6 ft. Wave Detail: S 5 ft at 15 seconds and E 3 ft at
8 seconds. A chance of showers this afternoon.
.TONIGHT...E winds 15 to 20 kt with gusts up to 25 kt. Seas 5 to
7 ft. Wave Detail: E 5 ft at 6 seconds and S 5 ft at 15 seconds.
Patchy fog. Showers likely, mainly in the evening. Vsby 1 to 3 NM
after midnight.
.THU...E winds 15 to 20 kt, becoming NE 20 to 25 kt in the
afternoon. Gusts up to 30 kt. Seas 5 to 7 ft, building to 6 to
9 ft in the afternoon. S and E of Nantucket, seas 8 to 10 ft,
building to 9 to 13 ft in the afternoon. Wave Detail: E 6 ft at
6 seconds and S 6 ft at 17 seconds, becoming E 7 ft at 6 seconds
and S 7 ft at 17 seconds. A chance of showers.
.THU NIGHT...NE winds 25 to 30 kt with gusts up to 40 kt. Seas
8 to 11 ft, building to 9 to 13 ft after midnight. S and E of
Nantucket, seas 12 to 16 ft, building to 14 to 19 ft after
midnight. Wave Detail: E 9 ft at 7 seconds and S 9 ft at
17 seconds, becoming E 11 ft at 8 seconds and S 11 ft at
18 seconds.
.FRI...NE winds 25 to 30 kt with gusts up to 45 kt. Seas 10 to
14 ft. S and E of Nantucket, seas 13 to 18 ft, subsiding to 12 to
16 ft in the afternoon. Wave Detail: NE 12 ft at 9 seconds and S
11 ft at 18 seconds.
.FRI NIGHT...N winds 25 to 30 kt with gusts up to 40 kt,
diminishing to 20 to 25 kt with gusts up to 30 kt after midnight.
Seas 9 to 13 ft. Wave Detail: NE 12 ft at 10 seconds and SE 7 ft
at 14 seconds.
.SAT...N winds 20 to 25 kt with gusts up to 30 kt. Seas 7 to
10 ft.
.SAT NIGHT...S winds 10 to 15 kt with gusts up to 25 kt. Seas
5 to 7 ft.
.SUN...S winds 10 to 15 kt with gusts up to 20 kt. Seas 4 to
6 ft.
.SUN NIGHT...S 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.

$$

ANZ255-202100-
Coastal Waters extending out to 25 nm South of Marthas Vineyard
and Nantucket-
404 AM EDT Wed Aug 20 2025

...SMALL CRAFT ADVISORY IN EFFECT THROUGH THURSDAY MORNING...
...GALE WATCH IN EFFECT FROM THURSDAY MORNING THROUGH LATE FRIDAY
NIGHT...

.TODAY...E winds 10 to 15 kt, increasing to 15 to 20 kt this
afternoon. Gusts up to 25 kt. Seas 5 to 7 ft. Wave Detail: S 6 ft
at 14 seconds and E 4 ft at 5 seconds. Patchy fog this afternoon.
A chance of showers this afternoon with vsby 1 to 3 NM.
.TONIGHT...E winds 20 to 25 kt with gusts up to 30 kt. Seas 6 to
9 ft. Wave Detail: E 7 ft at 6 seconds and S 7 ft at 17 seconds.
Patchy fog. Showers likely. Vsby 1 to 3 NM.
.THU...E winds 20 to 25 kt, becoming NE 25 to 30 kt in the
afternoon. Seas 8 to 11 ft. Wave Detail: S 9 ft at 17 seconds and
E 8 ft at 7 seconds. A chance of showers.
.THU NIGHT...NE winds 30 to 35 kt with gusts up to 40 kt. Seas
10 to 14 ft, building to 12 to 16 ft after midnight. Wave Detail:
S 14 ft at 18 seconds and E 9 ft at 7 seconds, becoming S 16 ft
at 18 seconds and E 10 ft at 8 seconds. A chance of showers.
.FRI...NE winds 30 to 35 kt with gusts up to 45 kt. Seas 11 to
15 ft, subsiding to 9 to 12 ft in the afternoon. S and E of
Nantucket, seas 13 to 18 ft, subsiding to 12 to 16 ft in the
afternoon. Wave Detail: S 14 ft at 17 seconds and NE 11 ft at
9 seconds, becoming NE 11 ft at 9 seconds and SE 8 ft at
14 seconds.
.FRI NIGHT...N winds 25 to 30 kt with gusts up to 40 kt,
diminishing to 20 to 25 kt with gusts up to 30 kt after midnight.
Seas 8 to 11 ft. Wave Detail: NE 10 ft at 10 seconds and NW 6 ft
at 6 seconds.
.SAT...N winds 20 to 25 kt with gusts up to 30 kt. Seas 6 to
9 ft.
.SAT NIGHT...S winds 10 to 15 kt with gusts up to 20 kt. Seas
4 to 6 ft.
.SUN...S winds 10 to 15 kt with gusts up to 20 kt. Seas 3 to
5 ft.
.SUN NIGHT...S 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.

$$

ANZ256-202100-
Coastal Waters from Montauk NY to Marthas Vineyard extending out
to 20 nm South of Block Island-
404 AM EDT Wed Aug 20 2025

...SMALL CRAFT ADVISORY IN EFFECT THROUGH THURSDAY MORNING...
...GALE WATCH IN EFFECT FROM THURSDAY MORNING THROUGH FRIDAY
AFTERNOON...

.TODAY...E winds 10 to 15 kt, increasing to 15 to 20 kt this
afternoon. Gusts up to 25 kt. Seas 6 to 7 ft. Wave Detail: S 6 ft
at 14 seconds and E 5 ft at 5 seconds. Patchy fog this afternoon.
Showers likely this afternoon with vsby 1 to 3 NM.
.TONIGHT...E winds 20 to 25 kt with gusts up to 30 kt. Seas 7 to
8 ft, building to 8 to 10 ft after midnight. Wave Detail: E 7 ft
at 6 seconds and S 5 ft at 15 seconds, becoming E 9 ft at
7 seconds and S 6 ft at 17 seconds. Patchy fog. Showers likely in
the evening. A chance of showers after midnight. Vsby 1 to 3 NM.
.THU...NE winds 25 to 30 kt with gusts up to 35 kt. Seas 9 to
11 ft, building to 9 to 13 ft in the afternoon. Wave Detail: E
9 ft at 7 seconds and S 7 ft at 16 seconds, becoming E 10 ft at
7 seconds and S 9 ft at 17 seconds. A chance of showers. Patchy
fog in the morning with vsby 1 to 3 NM.
.THU NIGHT...NE winds 30 to 35 kt with gusts up to 45 kt. Seas
12 to 16 ft, building to 14 to 17 ft after midnight. Wave Detail:
E 12 ft at 8 seconds and S 12 ft at 17 seconds, becoming S 14 ft
at 18 seconds and NE 13 ft at 8 seconds.
.FRI...NE winds 30 to 35 kt, becoming N 25 to 30 kt in the
afternoon. Gusts up to 45 kt. Seas 12 to 16 ft, subsiding to 9 to
13 ft in the afternoon. Wave Detail: N 13 ft at 7 seconds and S
13 ft at 17 seconds, becoming N 12 ft at 7 seconds and SE 7 ft at
14 seconds.
.FRI NIGHT...N winds 25 to 30 kt, becoming NW 20 to 25 kt after
midnight. Seas 7 to 10 ft. Wave Detail: NE 10 ft at 10 seconds
and SE 6 ft at 14 seconds.
.SAT...W winds 15 to 20 kt with gusts up to 25 kt. Seas 6 to
9 ft.
.SAT NIGHT AND SUN...S winds 10 to 15 kt. Gusts up to 20 kt. Seas
4 to 6 ft.
.SUN NIGHT...S winds around 15 kt with gusts up to 20 kt. Seas
4 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.

$$

ANZ232-202100-
Nantucket Sound-
404 AM EDT Wed Aug 20 2025

...GALE WATCH IN EFFECT FROM THURSDAY MORNING THROUGH LATE FRIDAY
NIGHT...

.TODAY...E winds 10 to 15 kt, increasing to 15 to 20 kt this
afternoon. Seas 2 to 4 ft. Wave Detail: E 3 ft at 4 seconds and S
2 ft at 14 seconds. A chance of showers this afternoon with vsby
1 to 3 NM.
.TONIGHT...E winds 15 to 20 kt, increasing to 20 to 25 kt after
midnight. Seas 3 to 5 ft. Wave Detail: E 4 ft at 5 seconds and S
2 ft at 15 seconds. Patchy fog. Showers likely. Vsby 1 to 3 NM.
.THU...NE winds 20 to 25 kt with gusts up to 30 kt. Seas 4 to
6 ft. Wave Detail: SE 5 ft at 5 seconds and S 3 ft at 16 seconds.
A chance of showers.
.THU NIGHT...NE winds 25 to 30 kt, increasing to 30 to 35 kt
after midnight. Seas 5 to 8 ft. Wave Detail: NE 7 ft at 6 seconds
and S 4 ft at 18 seconds.
.FRI AND FRI NIGHT...N winds 25 to 35 kt with gusts up to 40 kt.
Seas 5 to 7 ft. Wave Detail: N 7 ft at 6 seconds and S 3 ft at
18 seconds.
.SAT...NW winds 20 to 25 kt with gusts up to 30 kt. Seas 4 to
6 ft. Wave Detail: NW 4 ft at 4 seconds and E 4 ft at 11 seconds.
.SAT NIGHT...SW winds 10 to 15 kt with gusts up to 20 kt. Seas
3 to 5 ft.
.SUN...S winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to
3 ft.
.SUN NIGHT...S winds around 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.

$$

ANZ233-202100-
Vineyard Sound-
404 AM EDT Wed Aug 20 2025

...GALE WATCH IN EFFECT FROM THURSDAY MORNING THROUGH FRIDAY
AFTERNOON...

.TODAY...E winds 10 to 15 kt, increasing to 15 to 20 kt with
gusts up to 25 kt this afternoon. Seas 2 to 4 ft. Wave Detail: S
3 ft at 14 seconds and E 2 ft at 4 seconds. Showers likely this
afternoon with vsby 1 to 3 NM.
.TONIGHT...E winds 15 to 20 kt with gusts up to 25 kt. Seas 4 to
6 ft. Wave Detail: S 4 ft at 17 seconds and SE 3 ft at 4 seconds.
Patchy fog. Showers. Vsby 1 to 3 NM.
.THU...NE winds 20 to 25 kt with gusts up to 30 kt. Seas 5 to
7 ft. Wave Detail: S 5 ft at 17 seconds and NE 4 ft at 5 seconds.
A chance of showers.
.THU NIGHT...NE winds 25 to 30 kt with gusts up to 35 kt. Seas
7 to 10 ft. Wave Detail: S 7 ft at 17 seconds and NE 5 ft at
5 seconds.
.FRI...NE winds 25 to 30 kt with gusts up to 40 kt. Seas 6 to
9 ft, subsiding to 5 to 7 ft in the afternoon. Wave Detail: S
6 ft at 17 seconds and N 5 ft at 5 seconds, becoming N 4 ft at
6 seconds and S 4 ft at 14 seconds.
.FRI NIGHT...N winds 20 to 25 kt with gusts up to 30 kt. Seas
3 to 5 ft. Wave Detail: N 4 ft at 6 seconds and SE 3 ft at
13 seconds.
.SAT THROUGH SUN...S winds 15 to 20 kt with gusts up to 25 kt.
Seas 2 to 4 ft.
.SUN NIGHT...S 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.

$$

ANZ234-202100-
Buzzards Bay-
404 AM EDT Wed Aug 20 2025

...GALE WATCH IN EFFECT FROM THURSDAY MORNING THROUGH FRIDAY
AFTERNOON...

.TODAY...E winds 10 to 15 kt, increasing to 15 to 20 kt with
gusts up to 25 kt this afternoon. Seas 2 to 3 ft. Wave Detail: S
3 ft at 14 seconds and E 2 ft at 3 seconds. Showers likely this
afternoon with vsby 1 to 3 NM.
.TONIGHT...E winds 15 to 20 kt with gusts up to 25 kt. Seas 3 to
4 ft. Wave Detail: SE 3 ft at 4 seconds and S 3 ft at 15 seconds.
Patchy fog. Showers. Vsby 1 to 3 NM.
.THU...NE winds 15 to 20 kt, increasing to 20 to 25 kt in the
afternoon. Gusts up to 30 kt. Seas 4 to 6 ft. Wave Detail: NE
4 ft at 4 seconds and S 4 ft at 17 seconds. A chance of showers.
.THU NIGHT...NE winds 25 to 30 kt with gusts up to 35 kt. Seas
5 to 7 ft. Wave Detail: S 5 ft at 18 seconds and NE 4 ft at
4 seconds.
.FRI...N winds 25 to 30 kt with gusts up to 40 kt. Seas 4 to
6 ft. Wave Detail: S 5 ft at 17 seconds and N 4 ft at 6 seconds.
.FRI NIGHT...N winds 20 to 25 kt with gusts up to 35 kt, becoming
NW 15 to 20 kt with gusts up to 25 kt after midnight. Seas 3 to
5 ft. Wave Detail: N 4 ft at 6 seconds and SE 3 ft at 13 seconds.
.SAT THROUGH SUN...S winds 15 to 20 kt with gusts up to 25 kt.
Seas 2 to 3 ft.
.SUN NIGHT...S 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.

$$

ANZ235-202100-
Rhode Island Sound-
404 AM EDT Wed Aug 20 2025

...GALE WATCH IN EFFECT FROM THURSDAY MORNING THROUGH FRIDAY
AFTERNOON...

.TODAY...E winds 10 to 15 kt, increasing to 15 to 20 kt this
afternoon. Gusts up to 25 kt. Seas 4 to 6 ft. Wave Detail: S 5 ft
at 14 seconds and E 4 ft at 5 seconds. Patchy fog this afternoon.
Showers likely this afternoon with vsby 1 to 3 NM.
.TONIGHT...E winds 20 to 25 kt. Seas 5 to 8 ft. Wave Detail: E
7 ft at 7 seconds and S 6 ft at 17 seconds. Patchy fog. Showers
likely. Vsby 1 to 3 NM.
.THU...NE winds 20 to 25 kt with gusts up to 30 kt. Seas 6 to
8 ft, building to 7 to 10 ft in the afternoon. Wave Detail: E
7 ft at 7 seconds and S 6 ft at 16 seconds, becoming E 8 ft at
7 seconds and S 8 ft at 17 seconds. A chance of showers.
.THU NIGHT...NE winds 25 to 30 kt with gusts up to 40 kt. Seas
9 to 12 ft, building to 10 to 14 ft after midnight. Wave Detail:
S 11 ft at 17 seconds and E 8 ft at 7 seconds, becoming S 14 ft
at 18 seconds and NE 8 ft at 7 seconds.
.FRI...N winds 25 to 30 kt with gusts up to 40 kt. Seas 9 to
13 ft, subsiding to 6 to 9 ft in the afternoon. Wave Detail: S
13 ft at 17 seconds and NE 8 ft at 7 seconds, becoming N 8 ft at
7 seconds and SE 8 ft at 14 seconds.
.FRI NIGHT...N winds 20 to 25 kt, becoming NW 15 to 20 kt after
midnight. Gusts up to 30 kt. Seas 5 to 8 ft. Wave Detail: SE 7 ft
at 13 seconds and N 6 ft at 5 seconds.
.SAT...W winds 15 to 20 kt with gusts up to 25 kt. Seas 4 to
6 ft.
.SAT NIGHT AND SUN...S winds 10 to 15 kt. Gusts up to 20 kt. Seas
2 to 4 ft.
.SUN NIGHT...S winds around 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.

$$

ANZ237-202100-
Block Island Sound-
404 AM EDT Wed Aug 20 2025

...GALE WATCH IN EFFECT FROM THURSDAY MORNING THROUGH FRIDAY
AFTERNOON...

.TODAY...E winds 10 to 15 kt, increasing to 15 to 20 kt this
afternoon. Gusts up to 25 kt. Seas 4 to 6 ft. Wave Detail: S 5 ft
at 14 seconds and E 4 ft at 5 seconds. Patchy fog this afternoon.
A chance of showers this afternoon with vsby 1 to 3 NM.
.TONIGHT...E winds 20 to 25 kt. Seas 5 to 8 ft. Wave Detail: E
7 ft at 7 seconds and S 6 ft at 17 seconds. Patchy fog. Showers
likely. Vsby 1 to 3 NM.
.THU...NE winds 20 to 25 kt with gusts up to 30 kt. Seas 7 to
10 ft. Wave Detail: E 8 ft at 7 seconds and S 8 ft at 17 seconds.
A chance of showers. Patchy fog in the morning.
.THU NIGHT...NE winds 25 to 30 kt with gusts up to 35 kt. Seas
8 to 11 ft, building to 9 to 13 ft after midnight. Wave Detail: S
10 ft at 17 seconds and E 8 ft at 7 seconds, becoming S 12 ft at
18 seconds and E 8 ft at 8 seconds.
.FRI...N winds 25 to 30 kt, becoming NE 20 to 25 kt in the
afternoon. Gusts up to 40 kt. Seas 9 to 13 ft, subsiding to 7 to
10 ft in the afternoon. Wave Detail: S 12 ft at 17 seconds and E
8 ft at 8 seconds, becoming NE 8 ft at 7 seconds and SE 8 ft at
15 seconds.
.FRI NIGHT...N winds 15 to 20 kt with gusts up to 30 kt, becoming
NW with gusts up to 20 kt after midnight. Seas 5 to 8 ft. Wave
Detail: E 7 ft at 10 seconds and SE 7 ft at 13 seconds.
.SAT...W winds 10 to 15 kt with gusts up to 20 kt. Seas 4 to
6 ft.
.SAT NIGHT AND SUN...S winds 10 to 15 kt. Gusts up to 20 kt. Seas
3 to 4 ft.
.SUN NIGHT...S 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.

$$

ANZ230-202100-
Boston Harbor-
404 AM EDT Wed Aug 20 2025

.TODAY...E winds 5 to 10 kt, increasing to 10 to 15 kt with gusts
up to 20 kt this afternoon. Waves 1 foot or less, then around
2 ft this afternoon. A chance of showers this morning, then
showers likely this afternoon.
.TONIGHT...E winds 10 to 15 kt. Gusts up to 20 kt in the evening.
Waves around 2 ft. Showers likely, mainly in the evening. Patchy
fog in the evening with vsby 1 to 3 NM.
.THU...E winds 10 to 15 kt, becoming NE 15 to 20 kt in the
afternoon. Gusts up to 25 kt. Waves 2 to 3 ft.
.THU NIGHT...NE winds 15 to 20 kt with gusts up to 25 kt. Waves
2 to 3 ft.
.FRI...NE winds 15 to 20 kt with gusts up to 30 kt. Waves 2 to
3 ft.
.FRI NIGHT...NE winds 15 to 20 kt, becoming NW 10 to 15 kt after
midnight. Gusts up to 25 kt. Waves 2 to 3 ft, except 3 to 5 ft at
the outer harbor entrance.
.SAT THROUGH SUN...S winds 10 to 15 kt with gusts up to 25 kt.
Waves 2 to 3 ft.
.SUN NIGHT...S winds 10 to 15 kt with gusts up to 20 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.

$$

ANZ236-202100-
Narragansett Bay-
404 AM EDT Wed Aug 20 2025

.TODAY...E winds 5 to 10 kt, increasing to 10 to 15 kt with gusts
up to 20 kt this afternoon. Waves 2 to 4 ft. Patchy fog this
afternoon. Showers likely this afternoon with vsby 1 to 3 NM.
.TONIGHT...E winds 10 to 15 kt with gusts up to 20 kt. Waves 2 to
3 ft, except 4 to 6 ft at the bay entrance. Patchy fog. Showers.
Vsby 1 to 3 NM.
.THU...NE winds 15 to 20 kt with gusts up to 30 kt. Waves 2 to
3 ft, except 5 to 7 ft at the bay entrance. A chance of showers
in the morning.
.THU NIGHT...NE winds 20 to 25 kt with gusts up to 30 kt. Waves
around 3 ft, except 5 to 8 ft at the bay entrance.
.FRI...N winds 20 to 25 kt with gusts up to 35 kt. Waves around
3 ft, except 5 to 8 ft at the bay entrance.
.FRI NIGHT...N winds 15 to 20 kt with gusts up to 30 kt, becoming
NW 10 to 15 kt with gusts up to 20 kt after midnight. Waves 2 to
3 ft, except 4 to 6 ft at the bay entrance.
.SAT THROUGH SUN...S winds 10 to 15 kt with gusts up to 20 kt.
Waves 2 to 3 ft.
.SUN NIGHT...S winds 10 to 15 kt with gusts up to 20 kt. Waves
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.

$$

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