Coastal Waters Forecast
Issued by NWS Boston, MA

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FZUS51 KBOX 170805
CWFBOX

Coastal Waters Forecast for Massachusetts and Rhode Island
National Weather Service Boston/Norton MA
405 AM EDT Mon Aug 17 2026

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

ANZ200-172100-
405 AM EDT Mon Aug 17 2026

.Synopsis for Massachusetts and Rhode Island coastal waters...
High pres shifts east of the waters tonight. Low pres then
approaches from the west bringing gusty S winds and building seas
that have prompted Small Craft Advisories late tonight into Mon. The
associated cold front crosses the region late Mon into Mon night.
High pres returns Tue and Wed moving off the coast Thu ahead of the
next cold front.

$$

ANZ250-172100-
Coastal waters east of Ipswich Bay and the Stellwagen Bank
National Marine Sanctuary-
405 AM EDT Mon Aug 17 2026

.TODAY...S winds 10 to 15 kt with gusts up to 20 kt. Seas 3 to
4 ft. Wave Detail: S 3 ft at 4 seconds and SE 1 foot at
10 seconds. A chance of showers. Patchy fog this afternoon with
vsby 1 to 3 NM.
.TONIGHT...SE winds 5 to 10 kt, becoming NE after midnight. Seas
2 to 4 ft. Wave Detail: SE 2 ft at 4 seconds and SE 1 foot at
10 seconds. Patchy fog. A chance of showers. Vsby 1 to 3 NM.
.TUE...N winds 5 to 10 kt. Seas 2 to 4 ft. Wave Detail: SE 4 ft
at 6 seconds and N 1 foot at 2 seconds. Patchy fog in the morning
with vsby 1 to 3 NM.
.TUE NIGHT...N winds around 5 kt, becoming NW after midnight.
Seas 2 to 4 ft. Wave Detail: SE 4 ft at 8 seconds and S 2 ft at
7 seconds.
.WED...SW winds around 5 kt, becoming S in the afternoon. Seas
2 to 3 ft. Wave Detail: SE 3 ft at 8 seconds and S 2 ft at
7 seconds.
.WED NIGHT...SW winds 5 to 10 kt. Seas around 2 ft. Wave Detail:
SE 2 ft at 8 seconds and SW 1 foot at 4 seconds.
.THU THROUGH FRI NIGHT...E 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.

$$

ANZ251-172100-
Massachusetts Bay and Ipswich Bay-
405 AM EDT Mon Aug 17 2026

.TODAY...S winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to
3 ft. Wave Detail: SE 2 ft at 4 seconds and SE 1 foot at
10 seconds. Patchy fog. A chance of showers. Vsby 1 to 3 NM this
afternoon.
.TONIGHT...E winds 5 to 10 kt, becoming N after midnight. Seas
2 to 3 ft. Wave Detail: SE 2 ft at 4 seconds and SE 1 foot at
10 seconds. Patchy fog. A chance of showers in the evening. Vsby
1 to 3 NM.
.TUE...N winds 5 to 10 kt. Seas around 2 ft. Wave Detail: N
1 foot at 2 seconds and SE 1 foot at 4 seconds. Patchy fog in the
morning with vsby 1 to 3 NM.
.TUE NIGHT...NE winds around 5 kt, becoming W after midnight.
Seas around 2 ft. Wave Detail: E 2 ft at 9 seconds and NE 1 foot
at 4 seconds.
.WED...SW winds around 5 kt, becoming S in the afternoon. Seas
around 2 ft. Wave Detail: S 2 ft at 8 seconds and E 2 ft at
9 seconds.
.WED NIGHT...SW winds 5 to 10 kt. Seas around 2 ft. Wave Detail:
S 2 ft at 3 seconds and E 2 ft at 7 seconds.
.THU THROUGH FRI NIGHT...E 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.

$$

ANZ231-172100-
Cape Cod Bay-
405 AM EDT Mon Aug 17 2026

.TODAY...S winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to
3 ft. Wave Detail: SE 2 ft at 10 seconds and SW 1 foot at
3 seconds. A chance of showers this morning, then showers likely
this afternoon. Patchy fog this afternoon with vsby 1 to 3 NM.
.TONIGHT...SE winds 5 to 10 kt, becoming N after midnight. Seas
around 2 ft. Wave Detail: SE 2 ft at 10 seconds and SE 1 foot at
3 seconds. Patchy fog. A chance of showers in the evening. Vsby
1 NM or less.
.TUE...N winds 5 to 10 kt. Seas around 2 ft. Wave Detail: N
1 foot at 3 seconds and S 1 foot at 7 seconds. Patchy fog in the
morning with vsby 1 to 3 NM.
.TUE NIGHT...NW winds around 5 kt. Seas around 2 ft. Wave Detail:
S 2 ft at 7 seconds and N 1 foot at 3 seconds.
.WED...SW winds 5 to 10 kt. Seas around 2 ft in the morning, then
1 foot or less. Wave Detail: N 1 foot at 4 seconds and S 1 foot
at 7 seconds, becoming W 1 foot at 2 seconds and NE 1 foot at
4 seconds.
.WED NIGHT...SW winds 5 to 10 kt. Seas around 2 ft in the
evening, then 1 foot or less. Wave Detail: SW 1 foot at 3 seconds
and NE 1 foot at 4 seconds, becoming SW 1 foot at 2 seconds and
NE 1 foot at 4 seconds.
.THU...N winds around 5 kt. Seas 1 foot or less.
.THU NIGHT...SW winds around 5 kt. Seas 1 foot or less. A chance
of showers.
.FRI AND FRI NIGHT...NE winds 5 to 10 kt, becoming E. Seas 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.

$$

ANZ254-172100-
Coastal waters from Provincetown MA to Chatham MA to Nantucket MA
out 20 NM-
405 AM EDT Mon Aug 17 2026

...SMALL CRAFT ADVISORY IN EFFECT FROM 8 AM EDT THIS MORNING
THROUGH LATE TONIGHT...

.TODAY...S winds 10 to 15 kt with gusts up to 20 kt. Seas 3 to
5 ft. Wave Detail: SW 3 ft at 4 seconds and E 1 foot at
3 seconds. A chance of showers this morning, then showers likely
this afternoon. Patchy fog this afternoon with vsby 1 NM or less.
.TONIGHT...SE winds 10 to 15 kt with gusts up to 20 kt, becoming
N 5 to 10 kt after midnight. Seas 3 to 5 ft. Wave Detail: SE 3 ft
at 5 seconds and SE 2 ft at 10 seconds. Patchy fog. A chance of
showers in the evening. Vsby 1 NM or less.
.TUE...N winds 5 to 10 kt. Seas 2 to 4 ft. Wave Detail: SE 4 ft
at 7 seconds and NW 1 foot at 7 seconds. Patchy fog in the
morning with vsby 1 to 3 NM.
.TUE NIGHT...NW winds 5 to 10 kt. Seas 2 to 4 ft. Wave Detail: SE
4 ft at 8 seconds and S 2 ft at 7 seconds.
.WED AND WED NIGHT...SW winds 5 to 10 kt. Seas 2 to 3 ft. Wave
Detail: SE 3 ft at 7 seconds and NW 1 foot at 3 seconds.
.THU...W winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: SE 2 ft
at 7 seconds and W 1 foot at 3 seconds.
.THU NIGHT AND FRI...W winds 5 to 10 kt, becoming NE. Seas 2 to
3 ft. A chance of showers.
.FRI NIGHT...E 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.

$$

ANZ255-172100-
Coastal Waters extending out to 25 NM South of Marthas Vineyard
and Nantucket-
405 AM EDT Mon Aug 17 2026

...SMALL CRAFT ADVISORY IN EFFECT THROUGH LATE TONIGHT...

.TODAY...S winds 15 to 20 kt. Seas 3 to 5 ft. Wave Detail: S 4 ft
at 7 seconds and E 1 foot at 3 seconds. Showers likely. A slight
chance of tstms this afternoon. Patchy fog this afternoon with
vsby 1 NM or less.
.TONIGHT...SE winds 10 to 15 kt with gusts up to 20 kt, becoming
NW 5 to 10 kt after midnight. Seas 3 to 5 ft. Wave Detail: S 4 ft
at 7 seconds and SE 4 ft at 11 seconds. Patchy fog. A chance of
showers in the evening. Vsby 1 NM or less, increasing to 1 to
3 NM after midnight.
.TUE...NW winds 5 to 10 kt. Seas 3 to 4 ft. Wave Detail: S 4 ft
at 7 seconds and SE 3 ft at 8 seconds. Patchy fog in the morning
with vsby 1 to 3 NM.
.TUE NIGHT...NW winds around 5 kt. Seas 2 to 3 ft. Wave Detail: S
3 ft at 7 seconds and SE 3 ft at 8 seconds.
.WED AND WED NIGHT...SW winds 5 to 10 kt. Seas 2 to 3 ft. Wave
Detail: SW 2 ft at 3 seconds and S 2 ft at 7 seconds.
.THU...W winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: S 2 ft at
7 seconds and W 1 foot at 4 seconds.
.THU NIGHT THROUGH FRI NIGHT...E winds 5 to 10 kt. Seas 2 to
3 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.

$$

ANZ256-172100-
Coastal Waters from Montauk NY to Marthas Vineyard extending out
to 20 NM South of Block Island-
405 AM EDT Mon Aug 17 2026

...SMALL CRAFT ADVISORY IN EFFECT THROUGH LATE TONIGHT...

.TODAY...S winds 15 to 20 kt with gusts up to 25 kt. Seas 4 to
5 ft. Wave Detail: SW 5 ft at 6 seconds and E 1 foot at
4 seconds. Patchy fog. A slight chance of tstms. Showers likely
this morning, then a chance of showers this afternoon. Vsby 1 to
3 NM, decreasing to 1 NM or less this afternoon.
.TONIGHT...NE winds 5 to 10 kt, becoming NW after midnight. Seas
3 to 5 ft. Wave Detail: S 5 ft at 6 seconds and SE 5 ft at
10 seconds. Patchy fog. Vsby 1 NM or less, increasing to 1 to
3 NM after midnight.
.TUE...N winds 5 to 10 kt, becoming W in the afternoon. Seas 3 to
4 ft. Wave Detail: N 4 ft at 4 seconds and S 4 ft at 7 seconds.
Patchy fog in the morning with vsby 1 to 3 NM.
.TUE NIGHT...W winds around 5 kt. Seas 2 to 3 ft. Wave Detail: S
3 ft at 7 seconds and SE 2 ft at 8 seconds.
.WED AND WED NIGHT...SW winds 10 to 15 kt. Seas 2 to 3 ft. Wave
Detail: W 2 ft at 3 seconds and S 2 ft at 7 seconds.
.THU...W winds 5 to 10 kt. Seas around 2 ft. Wave Detail: S 2 ft
at 7 seconds and W 1 foot at 4 seconds.
.THU NIGHT THROUGH FRI NIGHT...E winds 5 to 10 kt. Seas 2 to
3 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.

$$

ANZ232-172100-
Nantucket Sound-
405 AM EDT Mon Aug 17 2026

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

.TODAY...S winds around 15 kt with gusts up to 20 kt. Seas 3 to
4 ft. Wave Detail: S 3 ft at 5 seconds and SE 2 ft at 10 seconds.
A chance of showers this morning, then showers likely this
afternoon. Patchy fog this afternoon with vsby 1 NM or less.
.TONIGHT...SE winds 10 to 15 kt with gusts up to 20 kt, becoming
NW 5 to 10 kt after midnight. Seas 2 to 4 ft. Wave Detail: SE
3 ft at 5 seconds and SE 2 ft at 10 seconds. Patchy fog. A chance
of showers in the evening. Vsby 1 NM or less, increasing to 1 to
3 NM after midnight.
.TUE...N winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: NW 1 foot
at 2 seconds and E 1 foot at 4 seconds. Patchy fog in the morning
with vsby 1 to 3 NM.
.TUE NIGHT...NW winds 5 to 10 kt. Seas around 2 ft. Wave Detail:
N 1 foot at 3 seconds and S 1 foot at 7 seconds.
.WED AND WED NIGHT...SW winds 10 to 15 kt. Seas around 2 ft. Wave
Detail: W 1 foot at 3 seconds and NE 1 foot at 4 seconds.
.THU...W winds 5 to 10 kt. Seas around 2 ft. Wave Detail: SW
1 foot at 4 seconds and NE 1 foot at 5 seconds.
.THU NIGHT THROUGH FRI NIGHT...E winds 5 to 10 kt. Seas 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.

$$

ANZ233-172100-
Vineyard Sound-
405 AM EDT Mon Aug 17 2026

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

.TODAY...S winds around 15 kt with gusts up to 20 kt. Seas 3 to
4 ft. Wave Detail: SW 4 ft at 6 seconds and E 2 ft at 4 seconds.
Patchy fog. Showers likely. A slight chance of tstms this
afternoon with vsby 1 NM or less.
.TONIGHT...SE winds 5 to 10 kt, becoming N after midnight. Seas
2 to 4 ft. Wave Detail: S 3 ft at 6 seconds and E 2 ft at
10 seconds. Patchy fog. A chance of showers in the evening. Vsby
1 NM or less, increasing to 1 to 3 NM after midnight.
.TUE...N winds 5 to 10 kt. Seas around 2 ft. Wave Detail: NE 2 ft
at 4 seconds and SW 2 ft at 7 seconds. Patchy fog in the morning
with vsby 1 to 3 NM.
.TUE NIGHT...NW winds around 5 kt. Seas around 2 ft. Wave Detail:
SW 2 ft at 6 seconds and N 1 foot at 3 seconds.
.WED AND WED NIGHT...SW winds 10 to 15 kt. Seas around 2 ft. Wave
Detail: S 2 ft at 6 seconds and SW 1 foot at 2 seconds.
.THU...W winds 5 to 10 kt. Seas around 2 ft. Wave Detail: SW 2 ft
at 5 seconds and NE 1 foot at 4 seconds.
.THU NIGHT THROUGH FRI NIGHT...E winds 5 to 10 kt. Seas around
2 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.

$$

ANZ234-172100-
Buzzards Bay-
405 AM EDT Mon Aug 17 2026

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

.TODAY...S winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to
4 ft. Wave Detail: SE 4 ft at 10 seconds and SW 3 ft at
4 seconds. Patchy fog. Showers likely. A slight chance of tstms
this afternoon with vsby 1 NM or less.
.TONIGHT...E winds 5 to 10 kt, becoming N after midnight. Seas
2 to 3 ft. Wave Detail: S 3 ft at 7 seconds and SE 3 ft at
10 seconds. Patchy fog. A chance of showers in the evening. Vsby
1 NM or less, increasing to 1 to 3 NM after midnight.
.TUE...N winds 5 to 10 kt. Seas around 2 ft. Wave Detail: N 2 ft
at 3 seconds and SW 2 ft at 7 seconds. Patchy fog in the morning
with vsby 1 to 3 NM.
.TUE NIGHT...NE winds around 5 kt, becoming NW around 5 kt after
midnight. Seas around 2 ft. Wave Detail: N 1 foot at 3 seconds
and SW 1 foot at 6 seconds.
.WED AND WED NIGHT...SW winds 10 to 15 kt with gusts up to 20 kt.
Seas around 2 ft. Wave Detail: SW 1 foot at 3 seconds and NE
1 foot at 4 seconds.
.THU...W winds 5 to 10 kt. Seas around 2 ft. Wave Detail: NE
1 foot at 4 seconds and SW 1 foot at 5 seconds.
.THU NIGHT...W winds 5 to 10 kt. Seas around 2 ft. A chance of
showers.
.FRI...NE winds 5 to 10 kt. Seas 1 foot or less.
.FRI NIGHT...E winds 5 to 10 kt. Seas 1 foot or less. 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.

$$

ANZ235-172100-
Rhode Island Sound-
405 AM EDT Mon Aug 17 2026

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

.TODAY...SE winds 15 to 20 kt. Seas 4 to 5 ft. Wave Detail: S
5 ft at 5 seconds and SE 4 ft at 10 seconds. Patchy fog. Showers
this morning, then a chance of showers with a slight chance of
tstms this afternoon. Vsby 1 to 3 NM, decreasing to 1 NM or less
this afternoon.
.TONIGHT...NE winds 5 to 10 kt, becoming N after midnight. Seas
3 to 5 ft. Wave Detail: SE 5 ft at 10 seconds and S 4 ft at
6 seconds. Patchy fog. Vsby 1 NM or less, increasing to 1 to 3 NM
after midnight.
.TUE...N winds 5 to 10 kt, becoming W in the afternoon. Seas 2 to
3 ft. Wave Detail: NW 3 ft at 3 seconds and E 3 ft at 4 seconds.
Patchy fog in the morning with vsby 1 to 3 NM.
.TUE NIGHT...SW winds around 5 kt, becoming W after midnight.
Seas 2 to 3 ft. Wave Detail: S 3 ft at 7 seconds and SE 2 ft at
8 seconds.
.WED AND WED NIGHT...SW winds 10 to 15 kt. Seas 2 to 3 ft. Wave
Detail: W 2 ft at 3 seconds and S 2 ft at 7 seconds.
.THU...W winds 5 to 10 kt. Seas around 2 ft. Wave Detail: S 2 ft
at 7 seconds and W 1 foot at 3 seconds.
.THU NIGHT...W winds 5 to 10 kt. Seas around 2 ft. A chance of
showers.
.FRI...NE winds 5 to 10 kt. Seas around 2 ft.
.FRI NIGHT...E winds 5 to 10 kt. Seas around 2 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.

$$

ANZ237-172100-
Block Island Sound-
405 AM EDT Mon Aug 17 2026

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

.TODAY...S winds 10 to 15 kt with gusts up to 20 kt. Seas 3 to
5 ft. Wave Detail: S 4 ft at 5 seconds and SE 1 foot at
9 seconds. Patchy fog. Showers likely with a slight chance of
tstms this morning, then a chance of showers this afternoon. Vsby
1 to 3 NM, decreasing to 1 NM or less this afternoon.
.TONIGHT...N winds 5 to 10 kt. Seas 3 to 5 ft. Wave Detail: S
4 ft at 7 seconds and SE 3 ft at 8 seconds. Patchy fog. Vsby 1 to
3 NM.
.TUE...N winds around 5 kt, becoming SW in the afternoon. Seas
2 to 3 ft. Wave Detail: N 3 ft at 2 seconds and S 3 ft at
7 seconds. Patchy fog in the morning.
.TUE NIGHT...W winds around 5 kt. Seas 2 to 3 ft. Wave Detail: S
3 ft at 7 seconds and SE 2 ft at 8 seconds.
.WED AND WED NIGHT...SW winds 5 to 10 kt. Seas around 2 ft. Wave
Detail: S 2 ft at 7 seconds and SE 2 ft at 8 seconds.
.THU...W winds 5 to 10 kt. Seas around 2 ft. Wave Detail: SE 2 ft
at 7 seconds and W 1 foot at 2 seconds.
.THU NIGHT...W winds 5 to 10 kt. Seas around 2 ft. A chance of
showers.
.FRI...NE winds 5 to 10 kt. Seas around 2 ft.
.FRI NIGHT...E winds 5 to 10 kt. Seas around 2 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.

$$

ANZ230-172100-
Boston Harbor-
405 AM EDT Mon Aug 17 2026

.TODAY...SE winds 5 to 10 kt. Waves around 2 ft. Patchy fog.
Showers likely, mainly this morning. Vsby 1 to 3 NM this
afternoon.
.TONIGHT...E winds 5 to 10 kt, becoming N after midnight. Waves
1 foot or less. Patchy fog. A chance of showers in the evening.
Vsby 1 NM or less, increasing to 1 to 3 NM after midnight.
.TUE...N winds 5 to 10 kt. Waves 1 foot or less. Patchy fog in
the morning.
.TUE NIGHT...E winds around 5 kt, becoming SW after midnight.
Waves 1 foot or less.
.WED...SW winds around 5 kt, becoming S in the afternoon. Waves
1 foot or less.
.WED NIGHT...SW winds 5 to 10 kt. Waves 1 foot or less.
.THU AND THU NIGHT...N winds 5 to 10 kt, becoming W. Waves 1 foot
or less. A chance of showers.
.FRI AND FRI NIGHT...E 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.

$$

ANZ236-172100-
Narragansett Bay-
405 AM EDT Mon Aug 17 2026

.TODAY...SE winds 10 to 15 kt with gusts up to 20 kt. Waves 2 to
4 ft. Patchy fog. Showers likely this morning, then a chance of
showers with a slight chance of tstms this afternoon with vsby
1 NM or less.
.TONIGHT...NE winds 5 to 10 kt, becoming N after midnight. Waves
2 to 3 ft. Patchy fog. Vsby 1 NM or less, increasing to 1 to 3 NM
after midnight.
.TUE...N winds around 5 kt. Waves around 2 ft. Patchy fog in the
morning with vsby 1 to 3 NM.
.TUE NIGHT...S winds around 5 kt, becoming NW after midnight.
Waves around 2 ft.
.WED AND WED NIGHT...SW winds 5 to 10 kt. Waves around 2 ft.
.THU...W winds 5 to 10 kt. Waves around 2 ft.
.THU NIGHT...W winds 5 to 10 kt. Waves around 2 ft. A chance of
showers.
.FRI...NE winds 5 to 10 kt. Waves 1 foot or less.
.FRI NIGHT...E winds 5 to 10 kt. Waves 1 foot or less. A chance
of showers.

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.

$$

ANZ280-172100-
Ocean Waters from the Merrimack River to Plymouth from 40 to
60 NM-
405 AM EDT Mon Aug 17 2026

.TODAY...S winds 10 to 15 kt with gusts up to 25 kt. Seas 3 to
5 ft. Wave Detail: SW 3 ft at 4 seconds and E 2 ft at 4 seconds.
A chance of showers. Patchy fog this afternoon with vsby 1 to
3 NM.
.TONIGHT...SE winds 10 to 15 kt with gusts up to 20 kt, becoming
E 5 to 10 kt after midnight. Seas 4 to 5 ft, subsiding to 2 to
4 ft after midnight. Wave Detail: SE 3 ft at 5 seconds and SE
1 foot at 9 seconds, becoming SE 3 ft at 5 seconds and SE 2 ft at
9 seconds. Patchy fog. A chance of showers. Vsby 1 to 3 NM.
.TUE...N winds 5 to 10 kt. Seas 3 to 5 ft. Wave Detail: SE 5 ft
at 8 seconds and NE 2 ft at 5 seconds. Patchy fog in the morning
with vsby 1 to 3 NM.
.TUE NIGHT...N winds 5 to 10 kt, becoming NW after midnight. Seas
3 to 4 ft. Wave Detail: SE 4 ft at 8 seconds and N 2 ft at
4 seconds.
.WED AND WED NIGHT...SW winds 10 to 15 kt with gusts up to 20 kt.
Seas 2 to 3 ft. Wave Detail: SE 3 ft at 8 seconds and S 2 ft at
7 seconds.
.THU THROUGH FRI NIGHT...E winds 5 to 10 kt. Seas 2 to 3 ft. Wave
Detail: SE 3 ft at 8 seconds and N 2 ft at 4 seconds.

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.

$$

ANZ281-172100-
Ocean Waters from Provincetown to Nantucket from 20 to 60 NM-
405 AM EDT Mon Aug 17 2026

.TODAY...S winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to
4 ft, building to 4 to 5 ft this afternoon. Wave Detail: SW 2 ft
at 4 seconds and SE 1 foot at 9 seconds, becoming SW 3 ft at
5 seconds and E 1 foot at 3 seconds. A chance of showers this
morning, then showers likely this afternoon. Patchy fog this
afternoon with vsby 1 to 3 NM.
.TONIGHT...SE winds 10 to 15 kt with gusts up to 20 kt, becoming
S 5 to 10 kt after midnight. Seas 4 to 6 ft. Wave Detail: S 4 ft
at 7 seconds and SE 4 ft at 9 seconds. Patchy fog. A chance of
showers. Vsby 1 NM or less.
.TUE...NW winds around 10 kt. Seas 4 to 6 ft. Wave Detail: SE
5 ft at 8 seconds and S 4 ft at 7 seconds. Patchy fog in the
morning with vsby 1 to 3 NM.
.TUE NIGHT...NW winds 5 to 10 kt. Seas 3 to 4 ft. Wave Detail: SE
4 ft at 8 seconds and S 3 ft at 7 seconds.
.WED AND WED NIGHT...SW winds 5 to 10 kt. Seas 2 to 3 ft. Wave
Detail: SE 3 ft at 8 seconds and S 2 ft at 7 seconds.
.THU...SW winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: S 3 ft
at 7 seconds and W 1 foot at 3 seconds.
.THU NIGHT AND FRI...W winds around 5 kt, becoming NE. Seas 2 to
3 ft. A chance of showers.
.FRI NIGHT...E 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.

$$

ANZ282-172100-
Ocean Waters from Marthas Vineyard to Nantucket from 25 to 60 NM-
405 AM EDT Mon Aug 17 2026

.TODAY...S 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: SW
5 ft at 6 seconds and E 1 foot at 2 seconds. A chance of showers
this morning, then showers likely with a slight chance of tstms
this afternoon. Patchy fog this afternoon with vsby 1 NM or less.
.TONIGHT...S winds 10 to 15 kt with gusts up to 20 kt, becoming W
5 to 10 kt after midnight. Seas 4 to 5 ft. Wave Detail: SW 5 ft
at 7 seconds and SE 4 ft at 11 seconds. Patchy fog. A chance of
showers in the evening. Vsby 1 NM or less, increasing to 1 to
3 NM after midnight.
.TUE...NW winds 5 to 10 kt. Seas 4 to 5 ft. Wave Detail: S 5 ft
at 7 seconds and SE 3 ft at 8 seconds. Patchy fog in the morning
with vsby 1 to 3 NM.
.TUE NIGHT...NW winds around 5 kt. Seas 3 to 4 ft. Wave Detail: S
3 ft at 7 seconds and SE 3 ft at 8 seconds.
.WED AND WED NIGHT...SW winds 5 to 10 kt. Seas 2 to 3 ft. Wave
Detail: S 2 ft at 7 seconds and NW 1 foot at 3 seconds.
.THU...SW winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: E 2 ft
at 9 seconds and NE 1 foot at 4 seconds.
.THU NIGHT AND FRI...W winds 5 to 10 kt, becoming NE. Seas 2 to
3 ft. A chance of showers.
.FRI NIGHT...E winds 5 to 10 kt. Seas 2 to 3 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.

$$

ANZ283-172100-
Ocean Waters from Montauk NY to Marthas Vineyard from 25 to 60 NM-
405 AM EDT Mon Aug 17 2026

.TODAY...S winds 15 to 20 kt with gusts up to 25 kt. Seas 4 to
5 ft. Wave Detail: SW 5 ft at 6 seconds and E 1 foot at
4 seconds. Showers with a slight chance of tstms. Patchy fog this
afternoon with vsby 1 NM or less.
.TONIGHT...SW winds 5 to 10 kt with gusts up to 20 kt, becoming
NW after midnight. Seas 4 to 5 ft. Wave Detail: S 5 ft at
7 seconds and SE 5 ft at 12 seconds. Patchy fog. Vsby 1 to 3 NM.
.TUE...NW winds 5 to 10 kt. Seas 3 to 4 ft. Wave Detail: S 4 ft
at 7 seconds and SE 3 ft at 11 seconds. Patchy fog in the
morning.
.TUE NIGHT...W winds around 5 kt. Seas 2 to 3 ft. Wave Detail: S
3 ft at 7 seconds and SE 2 ft at 8 seconds.
.WED AND WED NIGHT...SW winds 5 to 10 kt. Seas 2 to 3 ft. Wave
Detail: SW 2 ft at 4 seconds and S 2 ft at 7 seconds.
.THU...W winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: SW 2 ft
at 5 seconds and SE 2 ft at 9 seconds.
.THU NIGHT AND FRI...W winds 5 to 10 kt, becoming NE. Seas 2 to
3 ft. A chance of showers.
.FRI NIGHT...E winds around 10 kt. Seas 2 to 3 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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