164
FZUS51 KBOX 231403
CWFBOX

Coastal Waters Forecast for Massachusetts and Rhode Island
National Weather Service Boston/Norton MA
1003 AM EDT Sat Aug 23 2025

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

ANZ200-240300-
1003 AM EDT Sat Aug 23 2025

.Synopsis for Massachusetts and Rhode Island coastal waters...
High surf and dangerous rip currents remain a threat through
today. Seas will gradually trend downward today through Sun. Breezy
SW winds shift S Sun ahead of a cold front expected to pass over the
waters Mon afternoon/evening.

$$

ANZ250-240300-
Coastal waters east of Ipswich Bay and the Stellwagen Bank
National Marine Sanctuary-
1003 AM EDT Sat Aug 23 2025

...SMALL CRAFT ADVISORY IN EFFECT THROUGH SUNDAY EVENING...

.THIS AFTERNOON...S winds around 10 kt, increasing to 15 to 20 kt
with gusts up to 25 kt. Seas 6 to 7 ft. Wave Detail: E 7 ft at
11 seconds and S 3 ft at 3 seconds.
.TONIGHT...S winds 15 to 20 kt, diminishing to 10 to 15 kt after
midnight. Gusts up to 30 kt. Seas 5 to 7 ft. Wave Detail: E 6 ft
at 11 seconds and S 4 ft at 4 seconds.
.SUN...S winds 10 to 15 kt, increasing to 15 to 20 kt in the
afternoon. Gusts up to 25 kt. Seas 4 to 6 ft. Wave Detail: E 5 ft
at 11 seconds and SW 3 ft at 4 seconds.
.SUN NIGHT...S winds 15 to 20 kt, diminishing to 10 to 15 kt
after midnight. Gusts up to 25 kt. Seas 3 to 5 ft. Wave Detail: E
4 ft at 11 seconds and S 3 ft at 4 seconds. A chance of showers
after midnight.
.MON...SE winds 10 to 15 kt. Gusts up to 20 kt in the morning.
Seas 3 to 4 ft. Wave Detail: SE 3 ft at 9 seconds and SW 2 ft at
4 seconds. A chance of showers.
.MON NIGHT...SW winds around 10 kt, becoming W with gusts up to
20 kt after midnight. Seas 3 to 5 ft. Wave Detail: SE 5 ft at
8 seconds and S 1 foot at 3 seconds. A chance of showers in the
evening.
.TUE THROUGH WED NIGHT...W winds 10 to 15 kt with gusts up to
20 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.

$$

ANZ251-240300-
Massachusetts Bay and Ipswich Bay-
1003 AM EDT Sat Aug 23 2025

...SMALL CRAFT ADVISORY IN EFFECT THROUGH SUNDAY MORNING...

.THIS AFTERNOON...S winds 10 to 15 kt. Gusts up to 25 kt. Seas
4 to 6 ft. Wave Detail: E 6 ft at 12 seconds and S 2 ft at
4 seconds.
.TONIGHT...S winds 15 to 20 kt, diminishing to 10 to 15 kt after
midnight. Gusts up to 25 kt. Seas 4 to 6 ft. Wave Detail: E 6 ft
at 11 seconds and S 3 ft at 4 seconds.
.SUN...S winds 10 to 15 kt with gusts up to 25 kt. Seas 3 to
5 ft. Wave Detail: E 5 ft at 11 seconds and S 2 ft at 4 seconds.
.SUN NIGHT...S winds 15 to 20 kt with gusts up to 25 kt,
diminishing to 10 to 15 kt after midnight. Seas 2 to 4 ft. Wave
Detail: E 4 ft at 10 seconds and S 2 ft at 4 seconds. A chance of
showers after midnight.
.MON...SE winds around 10 kt. Seas 2 to 3 ft. Wave Detail: E 3 ft
at 10 seconds and S 1 foot at 4 seconds. A chance of showers.
.MON NIGHT...SW winds around 10 kt, becoming W after midnight.
Seas 2 to 3 ft. Wave Detail: E 3 ft at 9 seconds and S 1 foot at
3 seconds. A chance of showers in the evening.
.TUE THROUGH WED NIGHT...W winds around 10 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.

$$

ANZ231-240300-
Cape Cod Bay-
1003 AM EDT Sat Aug 23 2025

.THIS AFTERNOON...S winds 10 to 15 kt. Gusts up to 25 kt. Seas
2 to 4 ft. Wave Detail: NE 3 ft at 8 seconds and S 2 ft at
3 seconds.
.TONIGHT...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.
.SUN...S winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to
3 ft. Wave Detail: E 3 ft at 10 seconds and S 2 ft at 3 seconds.
.SUN NIGHT...S winds 10 to 15 kt. Gusts up to 20 kt in the
evening. Seas 2 to 3 ft. Wave Detail: S 2 ft at 3 seconds and E
2 ft at 11 seconds. A chance of showers after midnight.
.MON...SE winds around 10 kt. Seas around 2 ft. Wave Detail: E
2 ft at 9 seconds and SE 1 foot at 3 seconds. A chance of
showers.
.MON NIGHT...SW winds around 10 kt, becoming W after midnight.
Seas around 2 ft. Wave Detail: SE 2 ft at 8 seconds and SW 1 foot
at 2 seconds. A chance of showers in the evening.
.TUE THROUGH WED 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.

$$

ANZ254-240300-
Coastal waters from Provincetown MA to Chatham MA to Nantucket MA
out 20 nm-
1003 AM EDT Sat Aug 23 2025

...SMALL CRAFT ADVISORY IN EFFECT THROUGH SUNDAY EVENING...

.THIS AFTERNOON...S winds 5 to 10 kt, increasing to 10 to 15 kt
with gusts up to 20 kt. Seas 5 to 8 ft. Wave Detail: E 8 ft at
12 seconds.
.TONIGHT...S winds 10 to 15 kt with gusts up to 20 kt. Seas 5 to
7 ft. Wave Detail: E 6 ft at 11 seconds and S 1 foot at
4 seconds.
.SUN...S winds 10 to 15 kt with gusts up to 20 kt. Seas 4 to
5 ft. Wave Detail: E 5 ft at 11 seconds and S 2 ft at 4 seconds.
.SUN NIGHT...S winds 10 to 15 kt with gusts up to 20 kt. Seas
3 to 5 ft. Wave Detail: E 4 ft at 11 seconds and S 2 ft at
4 seconds. A chance of showers after midnight with vsby 1 to
3 NM.
.MON...SE winds 10 to 15 kt with gusts up to 20 kt, becoming S in
the afternoon. Seas 3 to 4 ft, building to 4 to 6 ft in the
afternoon. Wave Detail: SE 4 ft at 8 seconds and S 2 ft at
4 seconds, becoming SE 5 ft at 8 seconds and S 1 foot at
4 seconds. A chance of showers. Vsby 1 to 3 NM.
.MON NIGHT...W winds around 10 kt. Seas 4 to 6 ft. Wave Detail:
SE 6 ft at 8 seconds and SW 1 foot at 3 seconds. A chance of
showers in the evening.
.TUE THROUGH WED NIGHT...W winds 10 to 15 kt with gusts up to
20 kt. Seas 3 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.

$$

ANZ255-240300-
Coastal Waters extending out to 25 nm South of Marthas Vineyard
and Nantucket-
1003 AM EDT Sat Aug 23 2025

...SMALL CRAFT ADVISORY IN EFFECT THROUGH SUNDAY EVENING...

.THIS AFTERNOON...S winds 5 to 10 kt, increasing to 10 to 15 kt.
Seas 5 to 7 ft. Wave Detail: E 6 ft at 12 seconds and SW 1 foot
at 3 seconds.
.TONIGHT...S winds 10 to 15 kt. Seas 4 to 6 ft. Wave Detail: E
6 ft at 11 seconds and SW 2 ft at 4 seconds.
.SUN...S winds 10 to 15 kt with gusts up to 20 kt. Seas 3 to
5 ft. Wave Detail: E 4 ft at 11 seconds and S 3 ft at 4 seconds.
.SUN NIGHT...S winds 10 to 15 kt. Gusts up to 20 kt in the
evening. Seas 3 to 5 ft. Wave Detail: E 4 ft at 12 seconds and S
3 ft at 4 seconds. A chance of showers after midnight with vsby
1 to 3 NM.
.MON...SE winds 10 to 15 kt, becoming SW in the afternoon. Seas
4 to 6 ft. Wave Detail: SE 6 ft at 8 seconds and S 1 foot at
4 seconds. A chance of showers. Vsby 1 to 3 NM in the morning.
.MON NIGHT...W winds 10 to 15 kt. Seas 4 to 5 ft. Wave Detail: S
5 ft at 8 seconds and SW 1 foot at 3 seconds.
.TUE THROUGH WED NIGHT...W winds 10 to 15 kt with gusts up to
20 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.

$$

ANZ256-240300-
Coastal Waters from Montauk NY to Marthas Vineyard extending out
to 20 nm South of Block Island-
1003 AM EDT Sat Aug 23 2025

...SMALL CRAFT ADVISORY IN EFFECT THROUGH SUNDAY EVENING...

.THIS AFTERNOON...SW winds 10 to 15 kt. Seas 4 to 6 ft. Wave
Detail: E 6 ft at 11 seconds and SW 2 ft at 3 seconds.
.TONIGHT...S winds 10 to 15 kt. Seas 4 to 6 ft. Wave Detail: E
5 ft at 11 seconds and SW 2 ft at 3 seconds.
.SUN...S winds 10 to 15 kt. Gusts up to 20 kt in the afternoon.
Seas 4 to 5 ft. Wave Detail: E 5 ft at 11 seconds and S 3 ft at
4 seconds.
.SUN NIGHT...S winds 10 to 15 kt. Gusts up to 20 kt in the
evening. Seas 3 to 4 ft. Wave Detail: SE 4 ft at 12 seconds and S
3 ft at 4 seconds. A chance of showers after midnight.
.MON...SE winds around 10 kt, becoming SW in the afternoon. Seas
3 to 5 ft. Wave Detail: SE 5 ft at 8 seconds. A chance of
showers.
.MON NIGHT...SW winds 10 to 15 kt, becoming NW after midnight.
Seas 4 to 5 ft. Wave Detail: S 5 ft at 8 seconds and W 1 foot at
3 seconds.
.TUE THROUGH WED NIGHT...W winds 10 to 15 kt with gusts up to
20 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.

$$

ANZ232-240300-
Nantucket Sound-
1003 AM EDT Sat Aug 23 2025

...SMALL CRAFT ADVISORY IN EFFECT UNTIL 7 PM EDT THIS EVENING...

.THIS AFTERNOON...SW winds 10 to 15 kt. Gusts up to 20 kt. Seas
2 to 4 ft. Wave Detail: SE 3 ft at 12 seconds and SW 2 ft at
3 seconds.
.TONIGHT...S winds 10 to 15 kt. Gusts up to 20 kt in the evening.
Seas 2 to 4 ft. Wave Detail: SE 3 ft at 12 seconds and S 2 ft at
3 seconds.
.SUN...S winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to
3 ft. Wave Detail: S 2 ft at 3 seconds and SE 2 ft at 12 seconds.
.SUN NIGHT...S winds 10 to 15 kt. Gusts up to 20 kt in the
evening. Seas 2 to 3 ft. Wave Detail: S 2 ft at 4 seconds and E
2 ft at 11 seconds. A chance of showers after midnight.
.MON...SE winds 10 to 15 kt, becoming S in the afternoon. Seas
2 to 3 ft. Wave Detail: S 2 ft at 4 seconds and E 2 ft at
9 seconds. A chance of showers.
.MON NIGHT...SW winds 10 to 15 kt, becoming W after midnight.
Seas 2 to 3 ft. Wave Detail: SW 2 ft at 3 seconds and SE 2 ft at
8 seconds.
.TUE THROUGH WED 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.

$$

ANZ233-240300-
Vineyard Sound-
1003 AM EDT Sat Aug 23 2025

.THIS AFTERNOON...SW winds 10 to 15 kt. Gusts up to 20 kt. Seas
2 to 3 ft. Wave Detail: SW 2 ft at 3 seconds and SE 2 ft at
10 seconds.
.TONIGHT...S winds 10 to 15 kt. Seas 2 to 3 ft. Wave Detail: SW
2 ft at 4 seconds and SE 2 ft at 10 seconds.
.SUN...S winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to
3 ft. Wave Detail: S 2 ft at 4 seconds and SE 1 foot at
10 seconds.
.SUN NIGHT...S winds 10 to 15 kt. Gusts up to 20 kt in the
evening. Seas 2 to 3 ft. Wave Detail: S 2 ft at 4 seconds and SE
2 ft at 11 seconds. A chance of showers after midnight.
.MON...SE winds around 10 kt, becoming SW in the afternoon. Seas
2 to 3 ft. Wave Detail: SE 2 ft at 8 seconds and SE 1 foot at
4 seconds. A chance of showers.
.MON NIGHT...SW winds around 10 kt, becoming NW after midnight.
Seas 2 to 3 ft. Wave Detail: S 3 ft at 8 seconds and SW 1 foot at
3 seconds.
.TUE THROUGH WED 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.

$$

ANZ234-240300-
Buzzards Bay-
1003 AM EDT Sat Aug 23 2025

.THIS AFTERNOON...SW winds 10 to 15 kt. Gusts up to 20 kt. Seas
2 to 3 ft. Wave Detail: SW 2 ft at 3 seconds and SE 2 ft at
10 seconds.
.TONIGHT...S winds 10 to 15 kt. Gusts up to 20 kt in the evening.
Seas 2 to 3 ft. Wave Detail: SW 2 ft at 4 seconds and SE 2 ft at
10 seconds.
.SUN...S winds 10 to 15 kt with gusts up to 25 kt. Seas 2 to
3 ft. Wave Detail: S 2 ft at 4 seconds and SE 1 foot at
10 seconds.
.SUN NIGHT...S winds 10 to 15 kt. Gusts up to 20 kt in the
evening. Seas 2 to 3 ft. Wave Detail: S 2 ft at 4 seconds and SE
2 ft at 11 seconds. A chance of showers after midnight.
.MON...SE winds around 10 kt, becoming SW with gusts up to 20 kt
in the afternoon. Seas around 2 ft. Wave Detail: SE 2 ft at
8 seconds and SE 1 foot at 3 seconds. A chance of showers.
.MON NIGHT...SW winds around 10 kt, becoming W after midnight.
Seas around 2 ft. Wave Detail: S 2 ft at 8 seconds and SW 1 foot
at 3 seconds. A chance of showers in the evening.
.TUE THROUGH WED 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.

$$

ANZ235-240300-
Rhode Island Sound-
1003 AM EDT Sat Aug 23 2025

.THIS AFTERNOON...SW winds 10 to 15 kt. Gusts up to 20 kt. Seas
3 to 4 ft. Wave Detail: SE 4 ft at 11 seconds and SW 2 ft at
3 seconds.
.TONIGHT...S winds 10 to 15 kt. Gusts up to 20 kt in the evening.
Seas 2 to 4 ft. Wave Detail: SW 3 ft at 4 seconds and SE 3 ft at
11 seconds.
.SUN...S winds 10 to 15 kt. Gusts up to 20 kt in the afternoon.
Seas 2 to 3 ft. Wave Detail: S 3 ft at 4 seconds and SE 3 ft at
12 seconds.
.SUN NIGHT...S winds 10 to 15 kt. Gusts up to 20 kt in the
evening. Seas 2 to 3 ft. Wave Detail: S 3 ft at 5 seconds and SE
3 ft at 11 seconds. A chance of showers after midnight.
.MON...SE winds around 10 kt, becoming SW in the afternoon. Seas
2 to 4 ft. Wave Detail: SE 4 ft at 8 seconds and S 1 foot at
4 seconds. A chance of showers.
.MON NIGHT...SW winds 10 to 15 kt, becoming NW after midnight.
Seas 3 to 4 ft. Wave Detail: S 4 ft at 8 seconds.
.TUE THROUGH WED NIGHT...W winds 10 to 15 kt with gusts up to
20 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.

$$

ANZ237-240300-
Block Island Sound-
1003 AM EDT Sat Aug 23 2025

.THIS AFTERNOON...SW winds 10 to 15 kt. Gusts up to 20 kt. Seas
3 to 4 ft. Wave Detail: SE 4 ft at 11 seconds and SW 2 ft at
3 seconds.
.TONIGHT...S winds 10 to 15 kt. Gusts up to 20 kt in the evening.
Seas 3 to 4 ft. Wave Detail: SE 4 ft at 12 seconds and SW 2 ft at
3 seconds.
.SUN...S winds 10 to 15 kt. Gusts up to 20 kt in the afternoon.
Seas 2 to 4 ft. Wave Detail: SE 3 ft at 12 seconds and SW 2 ft at
4 seconds.
.SUN NIGHT...S winds 10 to 15 kt. Gusts up to 20 kt in the
evening. Seas 2 to 3 ft. Wave Detail: SE 3 ft at 12 seconds and S
2 ft at 4 seconds. A chance of showers after midnight.
.MON...SE winds around 10 kt, becoming SW in the afternoon. Seas
2 to 4 ft. Wave Detail: SE 4 ft at 7 seconds and S 1 foot at
4 seconds. A chance of showers.
.MON NIGHT...SW winds around 10 kt, becoming NW after midnight.
Seas 3 to 4 ft. Wave Detail: S 4 ft at 8 seconds and SW 1 foot at
3 seconds.
.TUE THROUGH WED NIGHT...W winds 10 to 15 kt with gusts up to
20 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.

$$

ANZ230-240300-
Boston Harbor-
1003 AM EDT Sat Aug 23 2025

.THIS AFTERNOON...S winds 5 to 10 kt, increasing to 10 to 15 kt
with gusts up to 20 kt. Waves 1 foot or less, then around 2 ft.
At the outer harbor entrance, waves 2 to 4 ft.
.TONIGHT...S winds 15 to 20 kt, diminishing to 10 to 15 kt after
midnight. Waves around 2 ft.
.SUN...S winds 10 to 15 kt. Gusts up to 20 kt in the afternoon.
Waves around 2 ft.
.SUN NIGHT...S winds 10 to 15 kt with gusts up to 20 kt,
diminishing to 5 to 10 kt after midnight. Waves around 2 ft in
the evening, then 1 foot or less. A chance of showers after
midnight.
.MON...SE winds 5 to 10 kt. Waves 1 foot or less, then around
2 ft in the afternoon. A chance of showers.
.MON NIGHT...W winds around 10 kt. Waves 1 foot or less. A chance
of showers in the evening.
.TUE THROUGH WED NIGHT...W winds 10 to 15 kt with gusts up to
20 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.

$$

ANZ236-240300-
Narragansett Bay-
1003 AM EDT Sat Aug 23 2025

.THIS AFTERNOON...S winds 10 to 15 kt. Gusts up to 20 kt. Waves
2 to 3 ft.
.TONIGHT...S winds 10 to 15 kt. Gusts up to 20 kt in the evening.
Waves around 2 ft.
.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,
diminishing to 5 to 10 kt after midnight. Waves around 2 ft. A
chance of showers after midnight.
.MON...S winds 5 to 10 kt, becoming SW in the afternoon. Waves
2 to 3 ft. A chance of showers.
.MON NIGHT...SW winds 5 to 10 kt, becoming NW after midnight.
Waves 2 to 3 ft. A chance of showers in the evening.
.TUE THROUGH WED 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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