Coastal Waters Forecast
Issued by NWS Boston, MA

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484
FZUS51 KBOX 210804
CWFBOX

Coastal Waters Forecast for Massachusetts and Rhode Island
National Weather Service Boston/Norton MA
404 AM EDT Tue Jul 21 2026

Coastal waters from the Merrimack River MA to Watch Hill RI out
to 60 NM

ANZ200-212100-
404 AM EDT Tue Jul 21 2026

.Synopsis for Massachusetts and Rhode Island coastal waters...
An approaching cold front will result in S-SW wind gusts approaching
gale force levels late Tue into Wed. Scattered thunderstorms may
result in even localized brief stronger wind gusts Tue night. In
addition...long southerly fetch will result in seas building to
between 7 and 12 feet across our southern waters by Wed. High pres
builds across the waters Thu into at least part of the weekend
bringing much lighter winds/lowering wave heights.

$$

ANZ250-212100-
Coastal waters east of Ipswich Bay and the Stellwagen Bank
National Marine Sanctuary-
404 AM EDT Tue Jul 21 2026

...SMALL CRAFT ADVISORY IN EFFECT FROM THIS EVENING THROUGH
WEDNESDAY EVENING...

.TODAY...S winds 10 to 15 kt, becoming SE 15 to 20 kt this
afternoon. Gusts up to 25 kt. Seas 2 to 3 ft. Wave Detail: S 3 ft
at 4 seconds and SE 3 ft at 7 seconds.
.TONIGHT...S winds 15 to 20 kt with gusts up to 30 kt. Seas 3 to
5 ft. Wave Detail: S 4 ft at 5 seconds and SE 1 foot at
11 seconds. Showers with a chance of tstms in the evening, then
showers likely after midnight.
.WED...S winds 15 to 20 kt with gusts up to 30 kt. Seas 4 to
6 ft. Wave Detail: S 5 ft at 7 seconds and SW 3 ft at 4 seconds.
A chance of showers.
.WED NIGHT...SW winds 15 to 20 kt with gusts up to 30 kt,
becoming W around 10 kt with gusts up to 20 kt after midnight.
Seas 4 to 6 ft. Wave Detail: S 5 ft at 7 seconds and SE 4 ft at
8 seconds. A chance of showers in the evening.
.THU...NW winds 5 to 10 kt, becoming SW in the afternoon. Seas
2 to 4 ft. Wave Detail: SE 4 ft at 10 seconds and S 3 ft at
6 seconds.
.THU NIGHT...S winds around 5 kt, becoming W after midnight. Seas
2 to 3 ft. Wave Detail: SE 3 ft at 8 seconds and NW 1 foot at
3 seconds.
.FRI THROUGH SAT NIGHT...E winds around 5 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.

$$

ANZ251-212100-
Massachusetts Bay and Ipswich Bay-
404 AM EDT Tue Jul 21 2026

.TODAY...S winds 10 to 15 kt, becoming SE 15 to 20 kt this
afternoon. Gusts up to 25 kt. Seas 2 to 3 ft. Wave Detail: S 3 ft
at 4 seconds and E 1 foot at 12 seconds.
.TONIGHT...S winds 15 to 20 kt with gusts up to 25 kt. Seas
around 3 ft. Wave Detail: S 3 ft at 4 seconds and E 1 foot at
11 seconds. Showers with a chance of tstms in the evening, then a
chance of showers after midnight.
.WED...S winds 15 to 20 kt, diminishing to 10 to 15 kt in the
afternoon. Gusts up to 25 kt. Seas 2 to 3 ft. Wave Detail: SE
3 ft at 6 seconds and SW 2 ft at 3 seconds. A chance of showers.
.WED NIGHT...SW winds 10 to 15 kt with gusts up to 25 kt,
becoming W 5 to 10 kt after midnight. Seas 2 to 3 ft. Wave
Detail: SW 3 ft at 4 seconds and SE 2 ft at 7 seconds. A chance
of showers in the evening.
.THU...NW winds 5 to 10 kt, becoming S in the afternoon. Seas
around 2 ft. Wave Detail: SE 2 ft at 9 seconds and W 1 foot at
2 seconds.
.THU NIGHT...S winds 5 to 10 kt, becoming W after midnight. Seas
around 2 ft. Wave Detail: E 2 ft at 7 seconds and S 2 ft at
8 seconds.
.FRI THROUGH SAT NIGHT...E 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.

$$

ANZ231-212100-
Cape Cod Bay-
404 AM EDT Tue Jul 21 2026

...SMALL CRAFT ADVISORY IN EFFECT FROM THIS EVENING THROUGH
WEDNESDAY EVENING...

.TODAY...S winds 10 to 15 kt with gusts up to 25 kt. Seas 2 to
3 ft. Wave Detail: SE 2 ft at 3 seconds and W 1 foot at
3 seconds.
.TONIGHT...S winds 15 to 20 kt with gusts up to 30 kt. Seas 3 to
5 ft. Wave Detail: SW 3 ft at 5 seconds and E 1 foot at
12 seconds. Showers with a chance of tstms in the evening, then
showers after midnight.
.WED...SW winds 15 to 20 kt with gusts up to 30 kt. Seas 3 to
4 ft. Wave Detail: SW 3 ft at 4 seconds and SE 1 foot at
7 seconds. Showers likely, mainly in the morning.
.WED NIGHT...SW winds 15 to 20 kt with gusts up to 25 kt,
becoming W 5 to 10 kt after midnight. Seas 2 to 4 ft. Wave
Detail: SW 3 ft at 4 seconds and SE 1 foot at 8 seconds. A chance
of showers.
.THU...NW winds 5 to 10 kt, becoming NE in the afternoon. Seas
around 2 ft. Wave Detail: S 2 ft at 7 seconds and NW 1 foot at
2 seconds.
.THU NIGHT...SE winds around 5 kt, becoming N around 5 kt after
midnight. Seas around 2 ft. Wave Detail: SE 2 ft at 7 seconds and
NW 1 foot at 3 seconds.
.FRI THROUGH SAT NIGHT...E 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.

$$

ANZ254-212100-
Coastal waters from Provincetown MA to Chatham MA to Nantucket MA
out 20 NM-
404 AM EDT Tue Jul 21 2026

...SMALL CRAFT ADVISORY IN EFFECT FROM THIS EVENING THROUGH
WEDNESDAY EVENING...

.TODAY...SE winds 10 to 15 kt with gusts up to 25 kt. Seas 2 to
3 ft. Wave Detail: S 3 ft at 5 seconds and W 1 foot at 3 seconds.
.TONIGHT...S winds 20 to 25 kt with gusts up to 35 kt. Seas 3 to
5 ft, building to 5 to 7 ft after midnight. Wave Detail: SW 5 ft
at 5 seconds and SE 1 foot at 8 seconds, becoming SE 7 ft at
7 seconds and W 2 ft at 5 seconds. Showers with a chance of tstms
in the evening, then showers after midnight.
.WED...S winds 20 to 25 kt with gusts up to 35 kt. Seas 6 to
9 ft. Wave Detail: SE 8 ft at 7 seconds and W 3 ft at 5 seconds.
Showers likely in the morning. A chance of showers in the
afternoon.
.WED NIGHT...SW winds 20 to 25 kt, becoming W 15 to 20 kt after
midnight. Gusts up to 30 kt. Seas 6 to 9 ft, subsiding to 5 to
7 ft after midnight. Wave Detail: S 8 ft at 8 seconds and SE 4 ft
at 9 seconds, becoming S 7 ft at 9 seconds and SE 4 ft at
10 seconds. A chance of showers.
.THU...NW winds 10 to 15 kt, becoming NE 5 to 10 kt in the
afternoon. Seas 5 to 7 ft. Wave Detail: S 6 ft at 9 seconds and E
3 ft at 10 seconds. A chance of showers.
.THU NIGHT...E winds around 5 kt, becoming N after midnight. Seas
4 to 6 ft. Wave Detail: S 4 ft at 8 seconds and SE 3 ft at
8 seconds. A chance of showers in the evening.
.FRI THROUGH SAT NIGHT...E winds 5 to 10 kt. Seas 2 to 4 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.

$$

ANZ255-212100-
Coastal Waters extending out to 25 NM South of Marthas Vineyard
and Nantucket-
404 AM EDT Tue Jul 21 2026

...SMALL CRAFT ADVISORY IN EFFECT FROM THIS EVENING THROUGH
WEDNESDAY EVENING...

.TODAY...SE winds 10 to 15 kt, increasing to 15 to 20 kt this
afternoon. Gusts up to 25 kt. Seas 2 to 3 ft. Wave Detail: S 3 ft
at 5 seconds and NW 1 foot at 6 seconds. A chance of showers this
afternoon.
.TONIGHT...S winds 20 to 25 kt, becoming SW 25 to 30 kt after
midnight. Seas 4 to 6 ft, building to 6 to 9 ft after midnight.
Wave Detail: SE 6 ft at 7 seconds and W 1 foot at 7 seconds,
becoming S 9 ft at 7 seconds and NW 2 ft at 7 seconds. Showers
with a chance of tstms.
.WED...SW winds 25 to 30 kt, diminishing to 20 to 25 kt in the
afternoon. Seas 7 to 10 ft. Wave Detail: SW 10 ft at 7 seconds
and E 1 foot at 8 seconds. Showers with a chance of tstms in the
morning, then a chance of showers in the afternoon.
.WED NIGHT...SW winds 20 to 25 kt, becoming W 15 to 20 kt after
midnight. Gusts up to 30 kt. Seas 6 to 9 ft. Wave Detail: S 9 ft
at 9 seconds and W 1 foot at 7 seconds. A chance of showers in
the evening. Showers likely after midnight.
.THU...N winds around 10 kt, becoming NE in the afternoon. Seas
6 to 9 ft, subsiding to 5 to 7 ft in the afternoon. Wave Detail:
S 7 ft at 9 seconds and NW 1 foot at 4 seconds, becoming S 6 ft
at 8 seconds and N 1 foot at 7 seconds. A chance of showers.
.THU NIGHT...E winds 5 to 10 kt, becoming NE after midnight. Seas
4 to 6 ft. Wave Detail: S 5 ft at 8 seconds and E 1 foot at
7 seconds. A chance of showers in the evening.
.FRI THROUGH SAT NIGHT...E winds 5 to 10 kt. Seas 2 to 4 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.

$$

ANZ256-212100-
Coastal Waters from Montauk NY to Marthas Vineyard extending out
to 20 NM South of Block Island-
404 AM EDT Tue Jul 21 2026

...SMALL CRAFT ADVISORY IN EFFECT FROM THIS EVENING THROUGH
WEDNESDAY EVENING...

.TODAY...SE winds 10 to 15 kt, increasing to 15 to 20 kt this
afternoon. Gusts up to 25 kt. Seas 2 to 4 ft. Wave Detail: SE
4 ft at 7 seconds and NW 1 foot at 3 seconds. Showers likely with
a slight chance of tstms this afternoon.
.TONIGHT...S winds 20 to 25 kt, becoming SW 25 to 30 kt after
midnight. Seas 4 to 6 ft, building to 6 to 9 ft after midnight.
Wave Detail: SE 6 ft at 7 seconds and W 2 ft at 6 seconds,
becoming S 9 ft at 7 seconds and NW 2 ft at 5 seconds. Showers
with a chance of tstms.
.WED...SW winds 25 to 30 kt, diminishing to 20 to 25 kt in the
afternoon. Seas 7 to 9 ft. Wave Detail: S 9 ft at 8 seconds and W
5 ft at 7 seconds. Showers likely, mainly in the morning.
.WED NIGHT...SW 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.
Seas 7 to 9 ft. Wave Detail: S 8 ft at 8 seconds and E 2 ft at
10 seconds. A chance of showers.
.THU...N winds around 10 kt, becoming NE in the afternoon. Seas
5 to 8 ft. Wave Detail: S 6 ft at 9 seconds and NW 1 foot at
8 seconds.
.THU NIGHT...E winds 5 to 10 kt, becoming NE after midnight. Seas
4 to 6 ft. Wave Detail: S 5 ft at 8 seconds and W 1 foot at
8 seconds.
.FRI THROUGH SAT NIGHT...NE winds 5 to 10 kt. Seas 3 to 4 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.

$$

ANZ232-212100-
Nantucket Sound-
404 AM EDT Tue Jul 21 2026

...SMALL CRAFT ADVISORY IN EFFECT FROM THIS EVENING THROUGH
WEDNESDAY EVENING...

.TODAY...S winds 10 to 15 kt, becoming SE 15 to 20 kt this
afternoon. Gusts up to 25 kt. Seas 2 to 3 ft. Wave Detail: SW
3 ft at 4 seconds and SE 2 ft at 8 seconds. A slight chance of
showers this afternoon.
.TONIGHT...S winds 20 to 25 kt, becoming SW 25 to 30 kt after
midnight. Seas 3 to 4 ft, building to 4 to 6 ft after midnight.
Wave Detail: SE 4 ft at 6 seconds and W 1 foot at 6 seconds,
becoming S 5 ft at 6 seconds and W 3 ft at 5 seconds. A chance of
tstms. Showers.
.WED...SW winds 25 to 30 kt, diminishing to 20 to 25 kt in the
afternoon. Seas 4 to 6 ft. Wave Detail: SW 5 ft at 6 seconds.
Showers likely, mainly in the morning.
.WED NIGHT...SW winds 20 to 25 kt, becoming W 15 to 20 kt after
midnight. Gusts up to 30 kt. Seas 4 to 6 ft. Wave Detail: SW 5 ft
at 5 seconds and E 2 ft at 10 seconds. A chance of showers.
.THU...NW winds around 10 kt, becoming NE in the afternoon. Seas
2 to 4 ft. Wave Detail: SW 2 ft at 7 seconds and E 2 ft at
10 seconds. A chance of showers in the morning.
.THU NIGHT...E winds 5 to 10 kt, becoming N after midnight. Seas
2 to 3 ft. Wave Detail: SW 2 ft at 5 seconds and E 2 ft at
7 seconds.
.FRI THROUGH SAT 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.

$$

ANZ233-212100-
Vineyard Sound-
404 AM EDT Tue Jul 21 2026

...SMALL CRAFT ADVISORY IN EFFECT FROM THIS EVENING THROUGH
WEDNESDAY EVENING...

.TODAY...S winds 10 to 15 kt, becoming SE 15 to 20 kt this
afternoon. Gusts up to 25 kt. Seas 2 to 3 ft. Wave Detail: S 3 ft
at 5 seconds and SE 3 ft at 8 seconds. A chance of showers with a
slight chance of tstms this afternoon.
.TONIGHT...S winds 20 to 25 kt with gusts up to 30 kt. Seas 3 to
4 ft, building to 4 to 6 ft after midnight. Wave Detail: SW 4 ft
at 6 seconds and E 1 foot at 12 seconds, becoming SW 6 ft at
7 seconds and SE 3 ft at 8 seconds. Showers with a chance of
tstms in the evening, then showers after midnight.
.WED...SW winds 20 to 25 kt with gusts up to 30 kt. Seas 5 to
7 ft. Wave Detail: SW 7 ft at 7 seconds and E 2 ft at 7 seconds.
Showers likely, mainly in the morning.
.WED NIGHT...SW winds 15 to 20 kt with gusts up to 30 kt,
becoming W 10 to 15 kt with gusts up to 20 kt after midnight.
Seas 4 to 6 ft. Wave Detail: SW 6 ft at 8 seconds and SE 2 ft at
9 seconds. A chance of showers.
.THU...N winds 5 to 10 kt. Seas 3 to 5 ft. Wave Detail: SW 4 ft
at 9 seconds and E 2 ft at 10 seconds.
.THU NIGHT...E winds 5 to 10 kt, becoming N after midnight. Seas
2 to 4 ft. Wave Detail: SW 3 ft at 8 seconds and E 1 foot at
7 seconds.
.FRI THROUGH SAT NIGHT...NE 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.

$$

ANZ234-212100-
Buzzards Bay-
404 AM EDT Tue Jul 21 2026

...SMALL CRAFT ADVISORY IN EFFECT FROM THIS EVENING THROUGH
WEDNESDAY EVENING...

.TODAY...S winds 10 to 15 kt, becoming SE 15 to 20 kt this
afternoon. Gusts up to 25 kt. Seas 2 to 3 ft. Wave Detail: SW
3 ft at 4 seconds and S 3 ft at 8 seconds. A chance of showers
with a slight chance of tstms this afternoon.
.TONIGHT...S winds 20 to 25 kt with gusts up to 30 kt. Seas 3 to
5 ft. Wave Detail: S 5 ft at 6 seconds and SE 1 foot at
12 seconds. Showers with a chance of tstms in the evening, then
showers after midnight.
.WED...SW winds 20 to 25 kt with gusts up to 35 kt. Seas 3 to
5 ft. Wave Detail: SW 5 ft at 6 seconds and SE 1 foot at
11 seconds. Showers likely, mainly in the morning.
.WED NIGHT...SW winds 15 to 20 kt with gusts up to 30 kt,
becoming NW around 10 kt after midnight. Seas 3 to 5 ft. Wave
Detail: SW 4 ft at 6 seconds and S 4 ft at 9 seconds. A chance of
showers.
.THU...NW winds 5 to 10 kt. Seas 2 to 4 ft. Wave Detail: E 2 ft
at 4 seconds and SW 2 ft at 9 seconds.
.THU NIGHT...E winds 5 to 10 kt, becoming N after midnight. Seas
2 to 3 ft. Wave Detail: SW 2 ft at 7 seconds and E 1 foot at
4 seconds.
.FRI THROUGH SAT NIGHT...NE 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.

$$

ANZ235-212100-
Rhode Island Sound-
404 AM EDT Tue Jul 21 2026

...SMALL CRAFT ADVISORY IN EFFECT FROM THIS EVENING THROUGH
WEDNESDAY EVENING...

.TODAY...S winds 10 to 15 kt, becoming SE 15 to 20 kt this
afternoon. Gusts up to 25 kt. Seas 2 to 3 ft. Wave Detail: S 3 ft
at 7 seconds and NW 1 foot at 3 seconds. A chance of showers with
a slight chance of tstms this afternoon.
.TONIGHT...S winds 20 to 25 kt with gusts up to 30 kt. Seas 5 to
7 ft. Wave Detail: S 7 ft at 7 seconds and W 3 ft at 6 seconds.
Showers. A chance of tstms in the evening.
.WED...SW winds 20 to 25 kt with gusts up to 30 kt. Seas 5 to
8 ft. Wave Detail: S 8 ft at 8 seconds and E 3 ft at 7 seconds.
Showers likely, mainly in the morning.
.WED NIGHT...SW winds 15 to 20 kt, becoming NW 10 to 15 kt after
midnight. Gusts up to 25 kt. Seas 5 to 7 ft. Wave Detail: S 7 ft
at 9 seconds and SE 4 ft at 9 seconds. A chance of showers.
.THU...N winds 5 to 10 kt, becoming SW in the afternoon. Seas
5 to 7 ft. Wave Detail: S 6 ft at 9 seconds and E 3 ft at
7 seconds.
.THU NIGHT...SE winds 5 to 10 kt, becoming N after midnight. Seas
3 to 5 ft. Wave Detail: S 4 ft at 8 seconds and E 2 ft at
9 seconds.
.FRI THROUGH SAT NIGHT...NE winds 5 to 10 kt. Seas 2 to 4 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.

$$

ANZ237-212100-
Block Island Sound-
404 AM EDT Tue Jul 21 2026

...SMALL CRAFT ADVISORY IN EFFECT FROM THIS EVENING THROUGH
WEDNESDAY EVENING...

.TODAY...SE 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. A chance of showers and tstms this afternoon.
.TONIGHT...S winds 20 to 25 kt with gusts up to 30 kt. Seas 3 to
5 ft, building to 5 to 7 ft after midnight. Wave Detail: SE 5 ft
at 6 seconds and W 2 ft at 6 seconds, becoming SW 7 ft at
6 seconds and SE 2 ft at 8 seconds. Showers with a chance of
tstms in the evening, then showers likely after midnight.
.WED...SW winds 15 to 20 kt with gusts up to 30 kt. Seas 5 to
7 ft. Wave Detail: SW 7 ft at 7 seconds and E 1 foot at
8 seconds. Showers likely, mainly in the morning.
.WED NIGHT...SW winds 15 to 20 kt with gusts up to 25 kt,
becoming NW 5 to 10 kt after midnight. Seas 5 to 7 ft. Wave
Detail: S 6 ft at 9 seconds and W 2 ft at 5 seconds. A chance of
showers in the evening.
.THU...N winds 5 to 10 kt, becoming SW in the afternoon. Seas
4 to 6 ft. Wave Detail: S 5 ft at 9 seconds and E 2 ft at
10 seconds.
.THU NIGHT...E winds 5 to 10 kt, becoming N after midnight. Seas
3 to 5 ft. Wave Detail: S 4 ft at 8 seconds and NW 1 foot at
7 seconds.
.FRI THROUGH SAT NIGHT...NE winds 5 to 10 kt. Seas 2 to 4 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.

$$

ANZ230-212100-
Boston Harbor-
404 AM EDT Tue Jul 21 2026

.TODAY...S winds 10 to 15 kt. Gusts up to 20 kt this afternoon.
Waves 2 to 3 ft. A slight chance of showers this afternoon.
.TONIGHT...S winds 15 to 20 kt with gusts up to 25 kt. Waves 2 to
3 ft. Showers. A chance of tstms in the evening.
.WED...SW winds 10 to 15 kt with gusts up to 20 kt. Waves around
2 ft. A chance of showers in the morning, then showers likely in
the afternoon.
.WED NIGHT...W 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 in the
evening.
.THU...NW winds 5 to 10 kt, becoming S in the afternoon. Waves
1 foot or less.
.THU NIGHT...S winds 5 to 10 kt, becoming W after midnight. Waves
1 foot or less.
.FRI THROUGH SAT NIGHT...E winds 5 to 10 kt. Waves 1 foot or
less.

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.

$$

ANZ236-212100-
Narragansett Bay-
404 AM EDT Tue Jul 21 2026

.TODAY...S winds 10 to 15 kt, becoming SE 15 to 20 kt this
afternoon. Gusts up to 25 kt. Waves 2 to 3 ft. A chance of
showers with isolated tstms this afternoon.
.TONIGHT...S winds 15 to 20 kt with gusts up to 30 kt. Waves 3 to
4 ft. Showers with a chance of tstms in the evening, then showers
likely after midnight.
.WED...SW winds 15 to 20 kt with gusts up to 30 kt. Waves 3 to
5 ft. A chance of showers.
.WED NIGHT...SW winds 10 to 15 kt with gusts up to 25 kt,
becoming NW 5 to 10 kt after midnight. Waves 2 to 4 ft. A chance
of showers in the evening.
.THU...NW winds 5 to 10 kt, becoming W in the afternoon. Waves
2 to 3 ft.
.THU NIGHT...W winds 5 to 10 kt, becoming N after midnight. Waves
2 to 3 ft.
.FRI THROUGH SAT NIGHT...NE winds 5 to 10 kt. Waves 2 to 3 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.

$$

ANZ280-212100-
Ocean Waters from the Merrimack River to Plymouth from 40 to
60 NM-
404 AM EDT Tue Jul 21 2026

.TODAY...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 W 1 foot at 3 seconds.
.TONIGHT...SE winds 15 to 20 kt, becoming S 20 to 25 kt after
midnight. Gusts up to 35 kt. Seas 4 to 6 ft. Wave Detail: S 6 ft
at 7 seconds and SE 5 ft at 10 seconds. Showers. A chance of
tstms in the evening.
.WED...S winds 20 to 25 kt with gusts up to 35 kt. Seas 6 to
9 ft. Wave Detail: S 8 ft at 6 seconds and S 1 foot at
11 seconds. A chance of showers.
.WED NIGHT...SW winds 20 to 25 kt, becoming W 10 to 15 kt after
midnight. Gusts up to 30 kt. Seas 6 to 9 ft. Wave Detail: S 8 ft
at 9 seconds and SW 2 ft at 5 seconds. A chance of showers.
.THU...W winds 5 to 10 kt. Seas 4 to 6 ft. Wave Detail: SE 6 ft
at 9 seconds and SE 2 ft at 10 seconds.
.THU NIGHT...S winds around 5 kt, becoming NW after midnight.
Seas 4 to 5 ft. Wave Detail: SE 5 ft at 8 seconds and NW 1 foot
at 3 seconds.
.FRI THROUGH SAT NIGHT...E winds around 5 kt. Seas 3 to 4 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.

$$

ANZ281-212100-
Ocean Waters from Provincetown to Nantucket from 20 to 60 NM-
404 AM EDT Tue Jul 21 2026

.TODAY...SE winds 5 to 10 kt, increasing to 10 to 15 kt this
afternoon. Gusts up to 20 kt. Seas 3 to 4 ft. Wave Detail: S 3 ft
at 7 seconds and SE 2 ft at 8 seconds.
.TONIGHT...S winds 15 to 20 kt, increasing to 20 to 25 kt after
midnight. Gusts up to 35 kt. Seas 3 to 5 ft, building to 5 to
8 ft after midnight. Wave Detail: SE 5 ft at 7 seconds and SW
2 ft at 4 seconds, becoming SW 8 ft at 6 seconds and E 3 ft at
8 seconds. Showers with a chance of tstms.
.WED...S winds 20 to 25 kt with gusts up to 35 kt. Seas 8 to
11 ft. Wave Detail: SW 10 ft at 7 seconds and E 4 ft at
7 seconds. Showers in the morning. A chance of showers in the
afternoon.
.WED NIGHT...SW winds 20 to 25 kt, diminishing to 15 to 20 kt
after midnight. Gusts up to 35 kt. Seas 9 to 11 ft, subsiding to
7 to 10 ft after midnight. Wave Detail: S 10 ft at 9 seconds and
SE 4 ft at 9 seconds, becoming S 9 ft at 9 seconds and SE 4 ft at
10 seconds. A chance of showers in the evening. Showers after
midnight.
.THU...W winds 10 to 15 kt with gusts up to 25 kt, becoming N
5 to 10 kt in the afternoon. Seas 7 to 10 ft. Wave Detail: S 8 ft
at 9 seconds and SE 4 ft at 9 seconds. Showers likely in the
morning. A chance of showers in the afternoon.
.THU NIGHT...E winds around 5 kt, becoming NE after midnight.
Seas 5 to 7 ft. Wave Detail: S 5 ft at 8 seconds and E 2 ft at
7 seconds. A chance of showers.
.FRI THROUGH SAT...E winds 5 to 10 kt. Seas 3 to 5 ft.
.SAT NIGHT...E winds 5 to 10 kt. Seas 3 to 4 ft. A chance of
showers.

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.

$$

ANZ282-212100-
Ocean Waters from Marthas Vineyard to Nantucket from 25 to 60 NM-
404 AM EDT Tue Jul 21 2026

.TODAY...SE winds 5 to 10 kt, increasing to 10 to 15 kt with
gusts up to 25 kt this afternoon. Seas 3 to 4 ft. Wave Detail: S
4 ft at 7 seconds and N 1 foot at 4 seconds. A slight chance of
showers this afternoon.
.TONIGHT...S winds 20 to 25 kt with gusts up to 35 kt. Seas 5 to
7 ft, building to 6 to 9 ft after midnight. Wave Detail: SE 6 ft
at 7 seconds and W 1 foot at 6 seconds, becoming SW 8 ft at
7 seconds and E 1 foot at 8 seconds. Showers with a chance of
tstms.
.WED...SW winds 25 to 30 kt with gusts up to 40 kt. Seas 9 to
12 ft. Wave Detail: SW 11 ft at 7 seconds and E 4 ft at
9 seconds. Showers. A chance of tstms in the morning.
.WED NIGHT...SW winds 20 to 25 kt with gusts up to 35 kt. Seas
9 to 12 ft. Wave Detail: S 10 ft at 9 seconds and E 3 ft at
10 seconds. Showers with a chance of tstms.
.THU...W winds 10 to 15 kt with gusts up to 25 kt, becoming NE
5 to 10 kt in the afternoon. Seas 8 to 11 ft. Wave Detail: S 8 ft
at 9 seconds and E 3 ft at 10 seconds. Showers likely.
.THU NIGHT...NE winds 5 to 10 kt. Seas 5 to 7 ft. Wave Detail: S
5 ft at 8 seconds and NW 1 foot at 5 seconds. A chance of
showers. A chance of tstms in the evening.
.FRI AND FRI NIGHT...NE winds 5 to 10 kt. Seas 3 to 5 ft.
.SAT AND SAT NIGHT...NE winds 5 to 10 kt. Seas 3 to 4 ft. A
chance of showers.

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.

$$

ANZ283-212100-
Ocean Waters from Montauk NY to Marthas Vineyard from 25 to 60 NM-
404 AM EDT Tue Jul 21 2026

.TODAY...SE winds 10 to 15 kt, increasing to 15 to 20 kt this
afternoon. Gusts up to 25 kt. Seas 3 to 5 ft. Wave Detail: S 5 ft
at 7 seconds and NW 1 foot at 4 seconds. A chance of showers with
isolated tstms this afternoon.
.TONIGHT...S winds 20 to 25 kt, becoming SW 25 to 30 kt after
midnight. Seas 5 to 7 ft, building to 7 to 10 ft after midnight.
Wave Detail: S 7 ft at 7 seconds and NW 2 ft at 6 seconds,
becoming S 9 ft at 7 seconds and NW 2 ft at 6 seconds. Showers
with a chance of tstms.
.WED...SW winds 25 to 30 kt, diminishing to 20 to 25 kt in the
afternoon. Seas 8 to 10 ft. Wave Detail: SW 10 ft at 9 seconds
and SW 6 ft at 6 seconds. Showers likely with a chance of tstms
in the morning, then a chance of showers in the afternoon.
.WED NIGHT...SW winds 20 to 25 kt, becoming W 15 to 20 kt after
midnight. Gusts up to 30 kt. Seas 8 to 11 ft. Wave Detail: S 9 ft
at 9 seconds and NE 3 ft at 9 seconds. A chance of showers in the
evening. Showers likely after midnight.
.THU...N winds 10 to 15 kt with gusts up to 20 kt, becoming NE
5 to 10 kt in the afternoon. Seas 6 to 9 ft. Wave Detail: S 7 ft
at 9 seconds and NE 2 ft at 7 seconds. A chance of showers.
.THU NIGHT...NE winds 5 to 10 kt. Seas 4 to 6 ft. Wave Detail: S
5 ft at 8 seconds and E 2 ft at 9 seconds. A chance of showers.
.FRI THROUGH SAT...NE winds 5 to 10 kt. Seas 3 to 4 ft.
.SAT NIGHT...NE winds 5 to 10 kt. Seas 3 to 4 ft. A chance of
showers.

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.

$$

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