FZUS51 KBOX 180503
CWFBOX
Coastal Waters Forecast for Massachusetts and Rhode Island
National Weather Service Boston/Norton MA
102 AM EDT Tue Aug 18 2026
Coastal waters from the Merrimack River MA to Watch Hill RI out
to 60 NM
ANZ200-181800-
102 AM EDT Tue Aug 18 2026
.Synopsis for Massachusetts and Rhode Island coastal waters...
An area of low-pressure moves over the south coastal waters this
afternoon and continues to support marginal SCY conditions over the
south coastal waters. This system moves east of the waters overnight
with diminsing winds and subsiding seas. Winds become light out of
the north/northeast on Tuesday with seas up to 3 feet over the outer
marine zones.
$$
ANZ250-181800-
Coastal waters east of Ipswich Bay and the Stellwagen Bank
National Marine Sanctuary-
102 AM EDT Tue Aug 18 2026
.REST OF TONIGHT...NE winds around 5 kt. Seas around 2 ft. Wave
Detail: SE 2 ft at 4 seconds and SE 1 foot at 9 seconds. Patchy
fog. A slight chance of showers. Vsby 1 NM or less.
.TUE...N winds around 5 kt. Seas 2 to 4 ft. Wave Detail: SE 3 ft
at 9 seconds and SW 2 ft at 6 seconds. Patchy fog in the morning
with vsby 1 NM or less.
.TUE NIGHT...N winds around 5 kt. Seas 2 to 4 ft. Wave Detail: SE
4 ft at 9 seconds and W 2 ft at 7 seconds. Patchy fog. Vsby 1 NM
or less.
.WED...W winds around 5 kt, becoming S in the afternoon. Seas
2 to 3 ft. Wave Detail: SE 3 ft at 8 seconds and SW 2 ft at
7 seconds. Patchy fog in the morning with vsby 1 NM or less.
.WED NIGHT...SW winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: SE
3 ft at 7 seconds and S 2 ft at 4 seconds.
.THU AND THU NIGHT...NW winds around 5 kt. Seas 2 to 3 ft. Wave
Detail: SE 2 ft at 8 seconds and SW 1 foot at 3 seconds.
.FRI AND FRI NIGHT...E winds 5 to 10 kt. Seas around 2 ft.
.SAT AND SAT NIGHT...E winds 5 to 10 kt. Seas 2 to 3 ft. A chance
of showers.
Seas are reported as significant wave height, which is the
average of the highest third of the waves. Individual wave
heights may be more than twice the significant wave height.
$$
ANZ251-181800-
Massachusetts Bay and Ipswich Bay-
102 AM EDT Tue Aug 18 2026
.REST OF TONIGHT...NE winds around 5 kt. Seas 1 foot or less.
Wave Detail: SE 1 foot at 4 seconds. Patchy fog. A slight chance
of showers. Vsby 1 NM or less.
.TUE...N winds around 5 kt. Seas 1 foot or less, then around 2 ft
in the afternoon. Wave Detail: SE 1 foot at 4 seconds, becoming
SE 2 ft at 7 seconds. Patchy fog in the morning with vsby 1 NM or
less.
.TUE NIGHT...NE winds around 5 kt, becoming NW after midnight.
Seas 2 to 3 ft. Wave Detail: E 3 ft at 9 seconds and N 1 foot at
2 seconds. Patchy fog after midnight with vsby 1 to 3 NM.
.WED...W winds around 5 kt, becoming S in the afternoon. Seas
around 2 ft. Wave Detail: SW 2 ft at 7 seconds and E 2 ft at
8 seconds. Patchy fog in the morning with vsby 1 to 3 NM.
.WED NIGHT...SW winds 5 to 10 kt. Seas around 2 ft. Wave Detail:
E 2 ft at 7 seconds and S 1 foot at 3 seconds.
.THU AND THU NIGHT...NW winds 5 to 10 kt. Seas around 2 ft. Wave
Detail: E 2 ft at 7 seconds and SW 1 foot at 2 seconds.
.FRI AND FRI NIGHT...NE winds 5 to 10 kt. Seas around 2 ft.
.SAT AND SAT 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.
$$
ANZ231-181800-
Cape Cod Bay-
102 AM EDT Tue Aug 18 2026
.REST OF TONIGHT...NE winds around 5 kt. Seas 1 foot or less.
Wave Detail: SE 1 foot at 3 seconds. Patchy fog. A slight chance
of showers. Vsby 1 NM or less.
.TUE...N winds around 5 kt. Seas 1 foot or less, then around 2 ft
in the afternoon. Wave Detail: E 1 foot at 2 seconds and S 1 foot
at 5 seconds, becoming SW 1 foot at 2 seconds and NE 1 foot at
3 seconds. Patchy fog in the morning with vsby 1 NM or less.
.TUE NIGHT...N winds around 5 kt. Seas around 2 ft. Wave Detail:
W 1 foot at 2 seconds and NE 1 foot at 4 seconds. Patchy fog
after midnight with vsby 1 NM or less.
.WED...W winds around 5 kt, becoming S in the afternoon. Seas
around 2 ft. Wave Detail: SW 1 foot at 2 seconds and E 1 foot at
5 seconds. Patchy fog in the morning with vsby 1 to 3 NM.
.WED NIGHT...SW winds 5 to 10 kt. Seas around 2 ft. Wave Detail:
SW 1 foot at 2 seconds and E 1 foot at 4 seconds.
.THU AND THU NIGHT...NW winds around 5 kt. Seas 1 foot or less.
Wave Detail: W 1 foot at 2 seconds and E 1 foot at 6 seconds. A
chance of showers.
.FRI THROUGH SAT NIGHT...E winds 5 to 10 kt. Seas around 2 ft. A
chance of showers.
Seas are reported as significant wave height, which is the
average of the highest third of the waves. Individual wave
heights may be more than twice the significant wave height.
$$
ANZ254-181800-
Coastal waters from Provincetown MA to Chatham MA to Nantucket MA
out 20 NM-
102 AM EDT Tue Aug 18 2026
...SMALL CRAFT ADVISORY IN EFFECT UNTIL 2 AM EDT EARLY THIS
MORNING...
.REST OF TONIGHT...E winds 5 to 10 kt. Seas 2 to 4 ft. Wave
Detail: S 3 ft at 6 seconds and SE 1 foot at 9 seconds. Patchy
fog. A slight chance of showers. Vsby 1 NM or less.
.TUE...N winds 5 to 10 kt. Seas 2 to 4 ft. Wave Detail: SE 4 ft
at 9 seconds and S 3 ft at 7 seconds. Patchy fog in the morning
with vsby 1 NM or less.
.TUE NIGHT...NW winds around 5 kt. Seas 2 to 4 ft. Wave Detail:
SE 4 ft at 8 seconds and SW 2 ft at 7 seconds. Patchy fog. Vsby
1 NM or less.
.WED...W winds around 5 kt, becoming SW in the afternoon. Seas
2 to 3 ft. Wave Detail: SE 3 ft at 8 seconds and S 2 ft at
7 seconds. Patchy fog in the morning with vsby 1 NM or less.
.WED NIGHT AND THU...SW winds 5 to 10 kt. Seas 2 to 3 ft. Wave
Detail: SE 3 ft at 7 seconds and SW 1 foot at 5 seconds.
.THU NIGHT...SW winds 5 to 10 kt, becoming W after midnight. Seas
2 to 3 ft. Wave Detail: SE 2 ft at 8 seconds and SW 1 foot at
4 seconds. A chance of showers.
.FRI THROUGH SAT NIGHT...SE winds 5 to 10 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.
$$
ANZ255-181800-
Coastal Waters extending out to 25 NM South of Marthas Vineyard
and Nantucket-
102 AM EDT Tue Aug 18 2026
...SMALL CRAFT ADVISORY IN EFFECT UNTIL 2 AM EDT EARLY THIS
MORNING...
.REST OF TONIGHT...N winds 5 to 10 kt. Seas 3 to 4 ft. Wave
Detail: S 4 ft at 7 seconds and E 1 foot at 4 seconds. Patchy
fog. Vsby 1 NM or less.
.TUE...N winds 5 to 10 kt. Seas 3 to 4 ft. Wave Detail: S 4 ft at
7 seconds and E 2 ft at 8 seconds. Patchy fog in the morning with
vsby 1 NM or less.
.TUE NIGHT...NW winds around 5 kt. Seas 2 to 4 ft. Wave Detail: S
3 ft at 7 seconds and SE 3 ft at 8 seconds. Patchy fog. Vsby 1 NM
or less.
.WED...SW winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: SE 2 ft
at 7 seconds. Patchy fog in the morning with vsby 1 NM or less.
.WED NIGHT AND THU...SW winds 5 to 10 kt. Seas 2 to 3 ft. Wave
Detail: SW 2 ft at 6 seconds and E 2 ft at 7 seconds.
.THU NIGHT...SW winds 5 to 10 kt, becoming NW after midnight.
Seas 2 to 3 ft. Wave Detail: SE 2 ft at 8 seconds and SW 1 foot
at 5 seconds. A chance of showers and tstms.
.FRI THROUGH SAT NIGHT...SE winds 10 to 15 kt. Seas 2 to 3 ft. A
chance of showers.
Winds and seas higher in and near tstms.
Seas are reported as significant wave height, which is the
average of the highest third of the waves. Individual wave
heights may be more than twice the significant wave height.
$$
ANZ256-181800-
Coastal Waters from Montauk NY to Marthas Vineyard extending out
to 20 NM South of Block Island-
102 AM EDT Tue Aug 18 2026
...SMALL CRAFT ADVISORY IN EFFECT UNTIL 2 AM EDT EARLY THIS
MORNING...
.REST OF TONIGHT...N winds 5 to 10 kt. Seas 3 to 4 ft. Wave
Detail: S 4 ft at 7 seconds and E 1 foot at 4 seconds. Patchy
fog. Vsby 1 NM or less.
.TUE...NW winds 5 to 10 kt. Seas 3 to 4 ft. Wave Detail: S 4 ft
at 7 seconds and E 3 ft at 9 seconds. Patchy fog in the morning
with vsby 1 NM or less.
.TUE NIGHT...W winds 5 to 10 kt. Seas around 3 ft. Wave Detail: S
3 ft at 7 seconds and SE 2 ft at 8 seconds. Patchy fog after
midnight with vsby 1 NM or less.
.WED...W winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: S 2 ft at
7 seconds and SE 2 ft at 8 seconds. Patchy fog in the morning
with vsby 1 NM or less.
.WED NIGHT...SW winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: S
2 ft at 6 seconds.
.THU...W winds 5 to 10 kt. Seas around 2 ft. Wave Detail: SW 2 ft
at 6 seconds and E 2 ft at 7 seconds. A chance of showers in the
afternoon.
.THU NIGHT...SW winds 5 to 10 kt, becoming NW after midnight.
Seas around 2 ft. A chance of showers. A chance of tstms after
midnight.
.FRI THROUGH SAT NIGHT...E winds 10 to 15 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.
$$
ANZ232-181800-
Nantucket Sound-
102 AM EDT Tue Aug 18 2026
.REST OF TONIGHT...NE winds 5 to 10 kt. Seas around 2 ft. Wave
Detail: SE 1 foot at 5 seconds. Patchy fog. Vsby 1 NM or less.
.TUE...N winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: NE 1 foot
at 4 seconds and SW 1 foot at 6 seconds. Patchy fog in the
morning with vsby 1 NM or less.
.TUE NIGHT...NW winds around 5 kt. Seas around 2 ft. Wave Detail:
SW 1 foot at 6 seconds and E 1 foot at 8 seconds. Patchy fog.
Vsby 1 to 3 NM.
.WED...W winds around 5 kt, becoming SW 10 to 15 kt in the
afternoon. Seas around 2 ft. Wave Detail: SW 2 ft at 6 seconds
and E 1 foot at 8 seconds. Patchy fog in the morning with vsby
1 NM or less.
.WED NIGHT...SW winds 10 to 15 kt, diminishing to 5 to 10 kt
after midnight. Seas around 2 ft. Wave Detail: SW 2 ft at
3 seconds and E 1 foot at 7 seconds.
.THU AND THU NIGHT...NW winds 5 to 10 kt. Seas around 2 ft. Wave
Detail: W 1 foot at 4 seconds and E 1 foot at 7 seconds. A chance
of showers.
.FRI THROUGH SAT NIGHT...E winds 10 to 15 kt. Seas around 2 ft. A
chance of showers.
Seas are reported as significant wave height, which is the
average of the highest third of the waves. Individual wave
heights may be more than twice the significant wave height.
$$
ANZ233-181800-
Vineyard Sound-
102 AM EDT Tue Aug 18 2026
.REST OF TONIGHT...N winds 5 to 10 kt. Seas 2 to 3 ft. Wave
Detail: SW 3 ft at 6 seconds and NE 1 foot at 3 seconds. Patchy
fog. Vsby 1 NM or less.
.TUE...N winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: SW 2 ft
at 6 seconds and N 1 foot at 3 seconds. Patchy fog in the morning
with vsby 1 NM or less.
.TUE NIGHT...NE winds around 5 kt, becoming NW after midnight.
Seas around 2 ft. Wave Detail: SW 2 ft at 6 seconds and NE 1 foot
at 6 seconds. Patchy fog after midnight with vsby 1 NM or less.
.WED...W winds around 5 kt, becoming SW 10 to 15 kt in the
afternoon. Seas around 2 ft. Wave Detail: SW 2 ft at 5 seconds
and SE 1 foot at 9 seconds. Patchy fog in the morning with vsby
1 NM or less.
.WED NIGHT...SW winds 10 to 15 kt, diminishing to 5 to 10 kt
after midnight. Seas around 2 ft. Wave Detail: SW 2 ft at
4 seconds and SE 1 foot at 9 seconds.
.THU AND THU NIGHT...NW winds 5 to 10 kt. Seas around 2 ft. Wave
Detail: SW 1 foot at 5 seconds and SE 1 foot at 8 seconds. A
chance of showers.
.FRI THROUGH SAT...E winds 5 to 10 kt. Seas around 2 ft. A chance
of showers.
.SAT NIGHT...E winds 5 to 10 kt. Seas around 2 ft. Showers
likely.
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.
$$
ANZ234-181800-
Buzzards Bay-
102 AM EDT Tue Aug 18 2026
.REST OF TONIGHT...N winds around 5 kt. Seas around 2 ft. Wave
Detail: SW 2 ft at 6 seconds and E 1 foot at 3 seconds. Patchy
fog. Vsby 1 NM or less.
.TUE...N winds around 5 kt. Seas around 2 ft. Wave Detail: NE
1 foot at 2 seconds and SW 1 foot at 6 seconds. Patchy fog in the
morning with vsby 1 NM or less.
.TUE NIGHT...N winds around 5 kt. Seas around 2 ft. Wave Detail:
E 1 foot at 3 seconds and SW 1 foot at 6 seconds. Patchy fog
after midnight with vsby 1 NM or less.
.WED...W winds around 5 kt, becoming SW 10 to 15 kt with gusts up
to 20 kt in the afternoon. Seas around 2 ft. Wave Detail: SW
1 foot at 5 seconds and SE 1 foot at 8 seconds. Patchy fog in the
morning with vsby 1 NM or less.
.WED NIGHT...SW winds 10 to 15 kt with gusts up to 20 kt,
diminishing to 5 to 10 kt after midnight. Seas around 2 ft. Wave
Detail: SW 2 ft at 4 seconds and SE 1 foot at 10 seconds.
.THU AND THU NIGHT...NW winds 5 to 10 kt. Seas around 2 ft. Wave
Detail: SW 1 foot at 4 seconds and SE 1 foot at 9 seconds. A
chance of showers.
.FRI THROUGH SAT NIGHT...E winds 5 to 10 kt. Seas around 2 ft. A
chance of showers.
Seas are reported as significant wave height, which is the
average of the highest third of the waves. Individual wave
heights may be more than twice the significant wave height.
$$
ANZ235-181800-
Rhode Island Sound-
102 AM EDT Tue Aug 18 2026
.REST OF TONIGHT...N winds 5 to 10 kt. Seas 2 to 3 ft. Wave
Detail: SE 3 ft at 7 seconds. Patchy fog. Vsby 1 NM or less.
.TUE...N winds 5 to 10 kt, becoming NW in the afternoon. Seas
2 to 3 ft. Wave Detail: SE 3 ft at 7 seconds. Patchy fog in the
morning with vsby 1 NM or less.
.TUE NIGHT...SW winds 5 to 10 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. Patchy fog after midnight with vsby 1 NM or less.
.WED...W winds around 5 kt, becoming SW 10 to 15 kt in the
afternoon. Seas 2 to 3 ft. Wave Detail: S 2 ft at 7 seconds and
SE 2 ft at 8 seconds. Patchy fog in the morning with vsby 1 NM or
less.
.WED NIGHT...SW winds 10 to 15 kt, diminishing to 5 to 10 kt
after midnight. Seas 2 to 3 ft. Wave Detail: SW 2 ft at 4 seconds
and SE 2 ft at 8 seconds.
.THU AND THU NIGHT...NW winds 5 to 10 kt. Seas around 2 ft. Wave
Detail: S 2 ft at 7 seconds. A chance of showers.
.FRI THROUGH SAT NIGHT...E winds 10 to 15 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.
$$
ANZ237-181800-
Block Island Sound-
102 AM EDT Tue Aug 18 2026
.REST OF TONIGHT...N winds around 5 kt. Seas 2 to 3 ft. Wave
Detail: SE 3 ft at 6 seconds. Patchy fog. Vsby 1 NM or less.
.TUE...N winds around 5 kt, becoming SW in the afternoon. Seas
2 to 3 ft. Wave Detail: S 3 ft at 7 seconds and SE 2 ft at
8 seconds. Patchy fog in the morning with vsby 1 NM or less.
.TUE NIGHT...SW winds around 5 kt, becoming NW after midnight.
Seas 2 to 3 ft. Wave Detail: S 3 ft at 7 seconds and SE 2 ft at
8 seconds. Patchy fog after midnight.
.WED...NW winds around 5 kt, becoming SW in the afternoon. Seas
2 to 3 ft. Wave Detail: S 2 ft at 7 seconds and SE 2 ft at
8 seconds. Patchy fog in the morning.
.WED NIGHT...SW winds 5 to 10 kt. Seas around 2 ft. Wave Detail:
SW 2 ft at 5 seconds and SE 2 ft at 8 seconds.
.THU AND THU NIGHT...N winds 5 to 10 kt. Seas around 2 ft. Wave
Detail: SW 2 ft at 6 seconds and SE 2 ft at 8 seconds. A chance
of showers.
.FRI THROUGH SAT NIGHT...E winds 5 to 10 kt. Seas 2 to 3 ft. A
chance of showers.
Seas are reported as significant wave height, which is the
average of the highest third of the waves. Individual wave
heights may be more than twice the significant wave height.
$$
ANZ230-181800-
Boston Harbor-
102 AM EDT Tue Aug 18 2026
.REST OF TONIGHT...NE winds around 5 kt. Waves 1 foot or less.
Patchy fog. A slight chance of showers. Vsby 1 NM or less.
.TUE...NE winds 5 to 10 kt. Waves 1 foot or less. Patchy fog in
the morning with vsby 1 NM or less.
.TUE NIGHT...E winds around 5 kt, becoming N after midnight.
Waves 1 foot or less. Patchy fog after midnight.
.WED...SW winds 5 to 10 kt. Waves 1 foot or less. Patchy fog in
the morning.
.WED NIGHT...SW winds 5 to 10 kt. Waves 1 foot or less.
.THU AND THU NIGHT...NW winds 5 to 10 kt. Waves 1 foot or less.
.FRI AND FRI NIGHT...NE winds 5 to 10 kt. Waves 1 foot or less.
.SAT AND SAT NIGHT...E winds 5 to 10 kt. Waves 1 foot or less. 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.
$$
ANZ236-181800-
Narragansett Bay-
102 AM EDT Tue Aug 18 2026
.REST OF TONIGHT...N winds around 5 kt. Waves around 2 ft. Patchy
fog. Vsby 1 NM or less.
.TUE...N winds around 5 kt. Waves around 2 ft. Patchy fog in the
morning with vsby 1 NM or less.
.TUE NIGHT...S winds around 5 kt, becoming NW around 5 kt after
midnight. Waves around 2 ft. Patchy fog after midnight with vsby
1 to 3 NM.
.WED...W winds around 5 kt, becoming SW in the afternoon. Waves
around 2 ft. Patchy fog in the morning.
.WED NIGHT...SW winds 5 to 10 kt. Waves around 2 ft.
.THU AND THU NIGHT...NW winds 5 to 10 kt. Waves around 2 ft. A
chance of showers.
.FRI THROUGH SAT NIGHT...E winds 5 to 10 kt. Waves around 2 ft. A
chance of showers.
Seas are reported as significant wave height, which is the
average of the highest third of the waves. Individual wave
heights may be more than twice the significant wave height.
$$
ANZ280-181800-
Ocean Waters from the Merrimack River to Plymouth from 40 to
60 NM-
102 AM EDT Tue Aug 18 2026
.REST OF TONIGHT...E winds 5 to 10 kt. Seas 2 to 3 ft. Wave
Detail: SE 2 ft at 5 seconds and SE 1 foot at 9 seconds. Patchy
fog. A chance of showers. Vsby 1 NM or less.
.TUE...NE winds 5 to 10 kt. Seas 3 to 5 ft. Wave Detail: SE 5 ft
at 9 seconds and SE 3 ft at 6 seconds. Patchy fog in the morning
with vsby 1 NM or less.
.TUE NIGHT...N winds around 5 kt. Seas 4 to 5 ft. Wave Detail: SE
5 ft at 9 seconds and SW 2 ft at 7 seconds. Patchy fog. Vsby 1 NM
or less.
.WED...W winds around 5 kt, becoming SW in the afternoon. Seas
3 to 4 ft. Wave Detail: SE 4 ft at 8 seconds and S 2 ft at
8 seconds. Patchy fog in the morning with vsby 1 NM or less.
.WED NIGHT...SW winds 10 to 15 kt with gusts up to 20 kt. Seas
around 3 ft. Wave Detail: S 3 ft at 7 seconds.
.THU AND THU NIGHT...NW winds 5 to 10 kt. Seas 2 to 3 ft. Wave
Detail: SW 2 ft at 6 seconds and SE 2 ft at 8 seconds.
.FRI AND FRI NIGHT...E winds 5 to 10 kt. Seas 2 to 3 ft.
.SAT AND SAT NIGHT...E winds 5 to 10 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.
$$
ANZ281-181800-
Ocean Waters from Provincetown to Nantucket from 20 to 60 NM-
102 AM EDT Tue Aug 18 2026
.REST OF TONIGHT...SE winds 5 to 10 kt. Seas 4 to 6 ft. Wave
Detail: S 4 ft at 6 seconds and SE 1 foot at 9 seconds. Patchy
fog. A chance of showers. Vsby 1 NM or less.
.TUE...N winds 5 to 10 kt. Seas 4 to 6 ft. Wave Detail: SE 5 ft
at 8 seconds and S 4 ft at 7 seconds. Patchy fog in the morning
with vsby 1 NM or less.
.TUE NIGHT...NW winds 5 to 10 kt. Seas 3 to 5 ft. Wave Detail: SE
5 ft at 8 seconds and SW 3 ft at 7 seconds. Patchy fog. Vsby 1 NM
or less.
.WED...SW winds 5 to 10 kt. Seas 3 to 4 ft. Wave Detail: S 3 ft
at 7 seconds. Patchy fog in the morning with vsby 1 NM or less.
.WED NIGHT AND THU...SW winds 5 to 10 kt. Seas around 3 ft. Wave
Detail: S 3 ft at 7 seconds.
.THU NIGHT...SW winds around 5 kt. Seas around 3 ft. Wave Detail:
SE 2 ft at 9 seconds and SW 1 foot at 5 seconds. A chance of
showers.
.FRI THROUGH SAT NIGHT...SE winds 5 to 10 kt. Seas 2 to 3 ft. A
chance of showers.
Seas are reported as significant wave height, which is the
average of the highest third of the waves. Individual wave
heights may be more than twice the significant wave height.
$$
ANZ282-181800-
Ocean Waters from Marthas Vineyard to Nantucket from 25 to 60 NM-
102 AM EDT Tue Aug 18 2026
.REST OF TONIGHT...W winds around 5 kt. Seas 4 to 6 ft. Wave
Detail: S 4 ft at 7 seconds and E 1 foot at 8 seconds. Patchy
fog. Vsby 1 NM or less.
.TUE...NW winds 5 to 10 kt. Seas 4 to 5 ft. Wave Detail: S 4 ft
at 7 seconds and E 3 ft at 8 seconds. Patchy fog in the morning
with vsby 1 NM or less.
.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. Patchy fog after
midnight with vsby 1 NM or less.
.WED...SW winds 5 to 10 kt. Seas around 3 ft. Wave Detail: SE
3 ft at 8 seconds and S 2 ft at 7 seconds. Patchy fog in the
morning with vsby 1 NM or less.
.WED NIGHT AND THU...SW winds 5 to 10 kt. Seas around 3 ft. Wave
Detail: S 2 ft at 7 seconds.
.THU NIGHT...W winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: SE
2 ft at 9 seconds and SW 1 foot at 4 seconds. A chance of showers
and tstms.
.FRI...NE winds 5 to 10 kt. 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.
.SAT AND SAT NIGHT...E winds around 10 kt, becoming S. Seas 2 to
4 ft. Showers likely.
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.
$$
ANZ283-181800-
Ocean Waters from Montauk NY to Marthas Vineyard from 25 to 60 NM-
102 AM EDT Tue Aug 18 2026
.REST OF TONIGHT...NW winds 5 to 10 kt. Seas 4 to 5 ft. Wave
Detail: S 4 ft at 7 seconds and NE 1 foot at 5 seconds. Patchy
fog. Vsby 1 NM or less.
.TUE...NW winds 5 to 10 kt. Seas 3 to 4 ft. Wave Detail: S 4 ft
at 7 seconds and NE 2 ft at 5 seconds. Patchy fog in the morning
with vsby 1 NM or less.
.TUE NIGHT...W winds 5 to 10 kt. Seas 3 to 4 ft. Wave Detail: S
3 ft at 7 seconds and SE 2 ft at 9 seconds. Patchy fog after
midnight with vsby 1 NM or less.
.WED...SW winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: S 2 ft
at 7 seconds and SE 2 ft at 8 seconds. Patchy fog in the morning
with vsby 1 to 3 NM.
.WED NIGHT AND THU...SW winds 5 to 10 kt. Seas 2 to 3 ft. Wave
Detail: S 2 ft at 7 seconds.
.THU NIGHT...SW winds 5 to 10 kt, becoming NW after midnight.
Seas 2 to 3 ft. Wave Detail: SE 2 ft at 9 seconds and SW 1 foot
at 4 seconds. A chance of showers and tstms.
.FRI THROUGH SAT...E winds 10 to 15 kt. Seas 2 to 3 ft. A chance
of showers.
.SAT NIGHT...SE winds 10 to 15 kt. Seas 3 to 4 ft. Showers
likely.
Winds and seas higher in and near tstms.
Seas are reported as significant wave height, which is the
average of the highest third of the waves. Individual wave
heights may be more than twice the significant wave height.
$$
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CWFBOX
Coastal Waters Forecast for Massachusetts and Rhode Island
National Weather Service Boston/Norton MA
102 AM EDT Tue Aug 18 2026
Coastal waters from the Merrimack River MA to Watch Hill RI out
to 60 NM
ANZ200-181800-
102 AM EDT Tue Aug 18 2026
.Synopsis for Massachusetts and Rhode Island coastal waters...
An area of low-pressure moves over the south coastal waters this
afternoon and continues to support marginal SCY conditions over the
south coastal waters. This system moves east of the waters overnight
with diminsing winds and subsiding seas. Winds become light out of
the north/northeast on Tuesday with seas up to 3 feet over the outer
marine zones.
$$
ANZ250-181800-
Coastal waters east of Ipswich Bay and the Stellwagen Bank
National Marine Sanctuary-
102 AM EDT Tue Aug 18 2026
.REST OF TONIGHT...NE winds around 5 kt. Seas around 2 ft. Wave
Detail: SE 2 ft at 4 seconds and SE 1 foot at 9 seconds. Patchy
fog. A slight chance of showers. Vsby 1 NM or less.
.TUE...N winds around 5 kt. Seas 2 to 4 ft. Wave Detail: SE 3 ft
at 9 seconds and SW 2 ft at 6 seconds. Patchy fog in the morning
with vsby 1 NM or less.
.TUE NIGHT...N winds around 5 kt. Seas 2 to 4 ft. Wave Detail: SE
4 ft at 9 seconds and W 2 ft at 7 seconds. Patchy fog. Vsby 1 NM
or less.
.WED...W winds around 5 kt, becoming S in the afternoon. Seas
2 to 3 ft. Wave Detail: SE 3 ft at 8 seconds and SW 2 ft at
7 seconds. Patchy fog in the morning with vsby 1 NM or less.
.WED NIGHT...SW winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: SE
3 ft at 7 seconds and S 2 ft at 4 seconds.
.THU AND THU NIGHT...NW winds around 5 kt. Seas 2 to 3 ft. Wave
Detail: SE 2 ft at 8 seconds and SW 1 foot at 3 seconds.
.FRI AND FRI NIGHT...E winds 5 to 10 kt. Seas around 2 ft.
.SAT AND SAT NIGHT...E winds 5 to 10 kt. Seas 2 to 3 ft. A chance
of showers.
Seas are reported as significant wave height, which is the
average of the highest third of the waves. Individual wave
heights may be more than twice the significant wave height.
$$
ANZ251-181800-
Massachusetts Bay and Ipswich Bay-
102 AM EDT Tue Aug 18 2026
.REST OF TONIGHT...NE winds around 5 kt. Seas 1 foot or less.
Wave Detail: SE 1 foot at 4 seconds. Patchy fog. A slight chance
of showers. Vsby 1 NM or less.
.TUE...N winds around 5 kt. Seas 1 foot or less, then around 2 ft
in the afternoon. Wave Detail: SE 1 foot at 4 seconds, becoming
SE 2 ft at 7 seconds. Patchy fog in the morning with vsby 1 NM or
less.
.TUE NIGHT...NE winds around 5 kt, becoming NW after midnight.
Seas 2 to 3 ft. Wave Detail: E 3 ft at 9 seconds and N 1 foot at
2 seconds. Patchy fog after midnight with vsby 1 to 3 NM.
.WED...W winds around 5 kt, becoming S in the afternoon. Seas
around 2 ft. Wave Detail: SW 2 ft at 7 seconds and E 2 ft at
8 seconds. Patchy fog in the morning with vsby 1 to 3 NM.
.WED NIGHT...SW winds 5 to 10 kt. Seas around 2 ft. Wave Detail:
E 2 ft at 7 seconds and S 1 foot at 3 seconds.
.THU AND THU NIGHT...NW winds 5 to 10 kt. Seas around 2 ft. Wave
Detail: E 2 ft at 7 seconds and SW 1 foot at 2 seconds.
.FRI AND FRI NIGHT...NE winds 5 to 10 kt. Seas around 2 ft.
.SAT AND SAT 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.
$$
ANZ231-181800-
Cape Cod Bay-
102 AM EDT Tue Aug 18 2026
.REST OF TONIGHT...NE winds around 5 kt. Seas 1 foot or less.
Wave Detail: SE 1 foot at 3 seconds. Patchy fog. A slight chance
of showers. Vsby 1 NM or less.
.TUE...N winds around 5 kt. Seas 1 foot or less, then around 2 ft
in the afternoon. Wave Detail: E 1 foot at 2 seconds and S 1 foot
at 5 seconds, becoming SW 1 foot at 2 seconds and NE 1 foot at
3 seconds. Patchy fog in the morning with vsby 1 NM or less.
.TUE NIGHT...N winds around 5 kt. Seas around 2 ft. Wave Detail:
W 1 foot at 2 seconds and NE 1 foot at 4 seconds. Patchy fog
after midnight with vsby 1 NM or less.
.WED...W winds around 5 kt, becoming S in the afternoon. Seas
around 2 ft. Wave Detail: SW 1 foot at 2 seconds and E 1 foot at
5 seconds. Patchy fog in the morning with vsby 1 to 3 NM.
.WED NIGHT...SW winds 5 to 10 kt. Seas around 2 ft. Wave Detail:
SW 1 foot at 2 seconds and E 1 foot at 4 seconds.
.THU AND THU NIGHT...NW winds around 5 kt. Seas 1 foot or less.
Wave Detail: W 1 foot at 2 seconds and E 1 foot at 6 seconds. A
chance of showers.
.FRI THROUGH SAT NIGHT...E winds 5 to 10 kt. Seas around 2 ft. A
chance of showers.
Seas are reported as significant wave height, which is the
average of the highest third of the waves. Individual wave
heights may be more than twice the significant wave height.
$$
ANZ254-181800-
Coastal waters from Provincetown MA to Chatham MA to Nantucket MA
out 20 NM-
102 AM EDT Tue Aug 18 2026
...SMALL CRAFT ADVISORY IN EFFECT UNTIL 2 AM EDT EARLY THIS
MORNING...
.REST OF TONIGHT...E winds 5 to 10 kt. Seas 2 to 4 ft. Wave
Detail: S 3 ft at 6 seconds and SE 1 foot at 9 seconds. Patchy
fog. A slight chance of showers. Vsby 1 NM or less.
.TUE...N winds 5 to 10 kt. Seas 2 to 4 ft. Wave Detail: SE 4 ft
at 9 seconds and S 3 ft at 7 seconds. Patchy fog in the morning
with vsby 1 NM or less.
.TUE NIGHT...NW winds around 5 kt. Seas 2 to 4 ft. Wave Detail:
SE 4 ft at 8 seconds and SW 2 ft at 7 seconds. Patchy fog. Vsby
1 NM or less.
.WED...W winds around 5 kt, becoming SW in the afternoon. Seas
2 to 3 ft. Wave Detail: SE 3 ft at 8 seconds and S 2 ft at
7 seconds. Patchy fog in the morning with vsby 1 NM or less.
.WED NIGHT AND THU...SW winds 5 to 10 kt. Seas 2 to 3 ft. Wave
Detail: SE 3 ft at 7 seconds and SW 1 foot at 5 seconds.
.THU NIGHT...SW winds 5 to 10 kt, becoming W after midnight. Seas
2 to 3 ft. Wave Detail: SE 2 ft at 8 seconds and SW 1 foot at
4 seconds. A chance of showers.
.FRI THROUGH SAT NIGHT...SE winds 5 to 10 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.
$$
ANZ255-181800-
Coastal Waters extending out to 25 NM South of Marthas Vineyard
and Nantucket-
102 AM EDT Tue Aug 18 2026
...SMALL CRAFT ADVISORY IN EFFECT UNTIL 2 AM EDT EARLY THIS
MORNING...
.REST OF TONIGHT...N winds 5 to 10 kt. Seas 3 to 4 ft. Wave
Detail: S 4 ft at 7 seconds and E 1 foot at 4 seconds. Patchy
fog. Vsby 1 NM or less.
.TUE...N winds 5 to 10 kt. Seas 3 to 4 ft. Wave Detail: S 4 ft at
7 seconds and E 2 ft at 8 seconds. Patchy fog in the morning with
vsby 1 NM or less.
.TUE NIGHT...NW winds around 5 kt. Seas 2 to 4 ft. Wave Detail: S
3 ft at 7 seconds and SE 3 ft at 8 seconds. Patchy fog. Vsby 1 NM
or less.
.WED...SW winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: SE 2 ft
at 7 seconds. Patchy fog in the morning with vsby 1 NM or less.
.WED NIGHT AND THU...SW winds 5 to 10 kt. Seas 2 to 3 ft. Wave
Detail: SW 2 ft at 6 seconds and E 2 ft at 7 seconds.
.THU NIGHT...SW winds 5 to 10 kt, becoming NW after midnight.
Seas 2 to 3 ft. Wave Detail: SE 2 ft at 8 seconds and SW 1 foot
at 5 seconds. A chance of showers and tstms.
.FRI THROUGH SAT NIGHT...SE winds 10 to 15 kt. Seas 2 to 3 ft. A
chance of showers.
Winds and seas higher in and near tstms.
Seas are reported as significant wave height, which is the
average of the highest third of the waves. Individual wave
heights may be more than twice the significant wave height.
$$
ANZ256-181800-
Coastal Waters from Montauk NY to Marthas Vineyard extending out
to 20 NM South of Block Island-
102 AM EDT Tue Aug 18 2026
...SMALL CRAFT ADVISORY IN EFFECT UNTIL 2 AM EDT EARLY THIS
MORNING...
.REST OF TONIGHT...N winds 5 to 10 kt. Seas 3 to 4 ft. Wave
Detail: S 4 ft at 7 seconds and E 1 foot at 4 seconds. Patchy
fog. Vsby 1 NM or less.
.TUE...NW winds 5 to 10 kt. Seas 3 to 4 ft. Wave Detail: S 4 ft
at 7 seconds and E 3 ft at 9 seconds. Patchy fog in the morning
with vsby 1 NM or less.
.TUE NIGHT...W winds 5 to 10 kt. Seas around 3 ft. Wave Detail: S
3 ft at 7 seconds and SE 2 ft at 8 seconds. Patchy fog after
midnight with vsby 1 NM or less.
.WED...W winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: S 2 ft at
7 seconds and SE 2 ft at 8 seconds. Patchy fog in the morning
with vsby 1 NM or less.
.WED NIGHT...SW winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: S
2 ft at 6 seconds.
.THU...W winds 5 to 10 kt. Seas around 2 ft. Wave Detail: SW 2 ft
at 6 seconds and E 2 ft at 7 seconds. A chance of showers in the
afternoon.
.THU NIGHT...SW winds 5 to 10 kt, becoming NW after midnight.
Seas around 2 ft. A chance of showers. A chance of tstms after
midnight.
.FRI THROUGH SAT NIGHT...E winds 10 to 15 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.
$$
ANZ232-181800-
Nantucket Sound-
102 AM EDT Tue Aug 18 2026
.REST OF TONIGHT...NE winds 5 to 10 kt. Seas around 2 ft. Wave
Detail: SE 1 foot at 5 seconds. Patchy fog. Vsby 1 NM or less.
.TUE...N winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: NE 1 foot
at 4 seconds and SW 1 foot at 6 seconds. Patchy fog in the
morning with vsby 1 NM or less.
.TUE NIGHT...NW winds around 5 kt. Seas around 2 ft. Wave Detail:
SW 1 foot at 6 seconds and E 1 foot at 8 seconds. Patchy fog.
Vsby 1 to 3 NM.
.WED...W winds around 5 kt, becoming SW 10 to 15 kt in the
afternoon. Seas around 2 ft. Wave Detail: SW 2 ft at 6 seconds
and E 1 foot at 8 seconds. Patchy fog in the morning with vsby
1 NM or less.
.WED NIGHT...SW winds 10 to 15 kt, diminishing to 5 to 10 kt
after midnight. Seas around 2 ft. Wave Detail: SW 2 ft at
3 seconds and E 1 foot at 7 seconds.
.THU AND THU NIGHT...NW winds 5 to 10 kt. Seas around 2 ft. Wave
Detail: W 1 foot at 4 seconds and E 1 foot at 7 seconds. A chance
of showers.
.FRI THROUGH SAT NIGHT...E winds 10 to 15 kt. Seas around 2 ft. A
chance of showers.
Seas are reported as significant wave height, which is the
average of the highest third of the waves. Individual wave
heights may be more than twice the significant wave height.
$$
ANZ233-181800-
Vineyard Sound-
102 AM EDT Tue Aug 18 2026
.REST OF TONIGHT...N winds 5 to 10 kt. Seas 2 to 3 ft. Wave
Detail: SW 3 ft at 6 seconds and NE 1 foot at 3 seconds. Patchy
fog. Vsby 1 NM or less.
.TUE...N winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: SW 2 ft
at 6 seconds and N 1 foot at 3 seconds. Patchy fog in the morning
with vsby 1 NM or less.
.TUE NIGHT...NE winds around 5 kt, becoming NW after midnight.
Seas around 2 ft. Wave Detail: SW 2 ft at 6 seconds and NE 1 foot
at 6 seconds. Patchy fog after midnight with vsby 1 NM or less.
.WED...W winds around 5 kt, becoming SW 10 to 15 kt in the
afternoon. Seas around 2 ft. Wave Detail: SW 2 ft at 5 seconds
and SE 1 foot at 9 seconds. Patchy fog in the morning with vsby
1 NM or less.
.WED NIGHT...SW winds 10 to 15 kt, diminishing to 5 to 10 kt
after midnight. Seas around 2 ft. Wave Detail: SW 2 ft at
4 seconds and SE 1 foot at 9 seconds.
.THU AND THU NIGHT...NW winds 5 to 10 kt. Seas around 2 ft. Wave
Detail: SW 1 foot at 5 seconds and SE 1 foot at 8 seconds. A
chance of showers.
.FRI THROUGH SAT...E winds 5 to 10 kt. Seas around 2 ft. A chance
of showers.
.SAT NIGHT...E winds 5 to 10 kt. Seas around 2 ft. Showers
likely.
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.
$$
ANZ234-181800-
Buzzards Bay-
102 AM EDT Tue Aug 18 2026
.REST OF TONIGHT...N winds around 5 kt. Seas around 2 ft. Wave
Detail: SW 2 ft at 6 seconds and E 1 foot at 3 seconds. Patchy
fog. Vsby 1 NM or less.
.TUE...N winds around 5 kt. Seas around 2 ft. Wave Detail: NE
1 foot at 2 seconds and SW 1 foot at 6 seconds. Patchy fog in the
morning with vsby 1 NM or less.
.TUE NIGHT...N winds around 5 kt. Seas around 2 ft. Wave Detail:
E 1 foot at 3 seconds and SW 1 foot at 6 seconds. Patchy fog
after midnight with vsby 1 NM or less.
.WED...W winds around 5 kt, becoming SW 10 to 15 kt with gusts up
to 20 kt in the afternoon. Seas around 2 ft. Wave Detail: SW
1 foot at 5 seconds and SE 1 foot at 8 seconds. Patchy fog in the
morning with vsby 1 NM or less.
.WED NIGHT...SW winds 10 to 15 kt with gusts up to 20 kt,
diminishing to 5 to 10 kt after midnight. Seas around 2 ft. Wave
Detail: SW 2 ft at 4 seconds and SE 1 foot at 10 seconds.
.THU AND THU NIGHT...NW winds 5 to 10 kt. Seas around 2 ft. Wave
Detail: SW 1 foot at 4 seconds and SE 1 foot at 9 seconds. A
chance of showers.
.FRI THROUGH SAT NIGHT...E winds 5 to 10 kt. Seas around 2 ft. A
chance of showers.
Seas are reported as significant wave height, which is the
average of the highest third of the waves. Individual wave
heights may be more than twice the significant wave height.
$$
ANZ235-181800-
Rhode Island Sound-
102 AM EDT Tue Aug 18 2026
.REST OF TONIGHT...N winds 5 to 10 kt. Seas 2 to 3 ft. Wave
Detail: SE 3 ft at 7 seconds. Patchy fog. Vsby 1 NM or less.
.TUE...N winds 5 to 10 kt, becoming NW in the afternoon. Seas
2 to 3 ft. Wave Detail: SE 3 ft at 7 seconds. Patchy fog in the
morning with vsby 1 NM or less.
.TUE NIGHT...SW winds 5 to 10 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. Patchy fog after midnight with vsby 1 NM or less.
.WED...W winds around 5 kt, becoming SW 10 to 15 kt in the
afternoon. Seas 2 to 3 ft. Wave Detail: S 2 ft at 7 seconds and
SE 2 ft at 8 seconds. Patchy fog in the morning with vsby 1 NM or
less.
.WED NIGHT...SW winds 10 to 15 kt, diminishing to 5 to 10 kt
after midnight. Seas 2 to 3 ft. Wave Detail: SW 2 ft at 4 seconds
and SE 2 ft at 8 seconds.
.THU AND THU NIGHT...NW winds 5 to 10 kt. Seas around 2 ft. Wave
Detail: S 2 ft at 7 seconds. A chance of showers.
.FRI THROUGH SAT NIGHT...E winds 10 to 15 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.
$$
ANZ237-181800-
Block Island Sound-
102 AM EDT Tue Aug 18 2026
.REST OF TONIGHT...N winds around 5 kt. Seas 2 to 3 ft. Wave
Detail: SE 3 ft at 6 seconds. Patchy fog. Vsby 1 NM or less.
.TUE...N winds around 5 kt, becoming SW in the afternoon. Seas
2 to 3 ft. Wave Detail: S 3 ft at 7 seconds and SE 2 ft at
8 seconds. Patchy fog in the morning with vsby 1 NM or less.
.TUE NIGHT...SW winds around 5 kt, becoming NW after midnight.
Seas 2 to 3 ft. Wave Detail: S 3 ft at 7 seconds and SE 2 ft at
8 seconds. Patchy fog after midnight.
.WED...NW winds around 5 kt, becoming SW in the afternoon. Seas
2 to 3 ft. Wave Detail: S 2 ft at 7 seconds and SE 2 ft at
8 seconds. Patchy fog in the morning.
.WED NIGHT...SW winds 5 to 10 kt. Seas around 2 ft. Wave Detail:
SW 2 ft at 5 seconds and SE 2 ft at 8 seconds.
.THU AND THU NIGHT...N winds 5 to 10 kt. Seas around 2 ft. Wave
Detail: SW 2 ft at 6 seconds and SE 2 ft at 8 seconds. A chance
of showers.
.FRI THROUGH SAT NIGHT...E winds 5 to 10 kt. Seas 2 to 3 ft. A
chance of showers.
Seas are reported as significant wave height, which is the
average of the highest third of the waves. Individual wave
heights may be more than twice the significant wave height.
$$
ANZ230-181800-
Boston Harbor-
102 AM EDT Tue Aug 18 2026
.REST OF TONIGHT...NE winds around 5 kt. Waves 1 foot or less.
Patchy fog. A slight chance of showers. Vsby 1 NM or less.
.TUE...NE winds 5 to 10 kt. Waves 1 foot or less. Patchy fog in
the morning with vsby 1 NM or less.
.TUE NIGHT...E winds around 5 kt, becoming N after midnight.
Waves 1 foot or less. Patchy fog after midnight.
.WED...SW winds 5 to 10 kt. Waves 1 foot or less. Patchy fog in
the morning.
.WED NIGHT...SW winds 5 to 10 kt. Waves 1 foot or less.
.THU AND THU NIGHT...NW winds 5 to 10 kt. Waves 1 foot or less.
.FRI AND FRI NIGHT...NE winds 5 to 10 kt. Waves 1 foot or less.
.SAT AND SAT NIGHT...E winds 5 to 10 kt. Waves 1 foot or less. 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.
$$
ANZ236-181800-
Narragansett Bay-
102 AM EDT Tue Aug 18 2026
.REST OF TONIGHT...N winds around 5 kt. Waves around 2 ft. Patchy
fog. Vsby 1 NM or less.
.TUE...N winds around 5 kt. Waves around 2 ft. Patchy fog in the
morning with vsby 1 NM or less.
.TUE NIGHT...S winds around 5 kt, becoming NW around 5 kt after
midnight. Waves around 2 ft. Patchy fog after midnight with vsby
1 to 3 NM.
.WED...W winds around 5 kt, becoming SW in the afternoon. Waves
around 2 ft. Patchy fog in the morning.
.WED NIGHT...SW winds 5 to 10 kt. Waves around 2 ft.
.THU AND THU NIGHT...NW winds 5 to 10 kt. Waves around 2 ft. A
chance of showers.
.FRI THROUGH SAT NIGHT...E winds 5 to 10 kt. Waves around 2 ft. A
chance of showers.
Seas are reported as significant wave height, which is the
average of the highest third of the waves. Individual wave
heights may be more than twice the significant wave height.
$$
ANZ280-181800-
Ocean Waters from the Merrimack River to Plymouth from 40 to
60 NM-
102 AM EDT Tue Aug 18 2026
.REST OF TONIGHT...E winds 5 to 10 kt. Seas 2 to 3 ft. Wave
Detail: SE 2 ft at 5 seconds and SE 1 foot at 9 seconds. Patchy
fog. A chance of showers. Vsby 1 NM or less.
.TUE...NE winds 5 to 10 kt. Seas 3 to 5 ft. Wave Detail: SE 5 ft
at 9 seconds and SE 3 ft at 6 seconds. Patchy fog in the morning
with vsby 1 NM or less.
.TUE NIGHT...N winds around 5 kt. Seas 4 to 5 ft. Wave Detail: SE
5 ft at 9 seconds and SW 2 ft at 7 seconds. Patchy fog. Vsby 1 NM
or less.
.WED...W winds around 5 kt, becoming SW in the afternoon. Seas
3 to 4 ft. Wave Detail: SE 4 ft at 8 seconds and S 2 ft at
8 seconds. Patchy fog in the morning with vsby 1 NM or less.
.WED NIGHT...SW winds 10 to 15 kt with gusts up to 20 kt. Seas
around 3 ft. Wave Detail: S 3 ft at 7 seconds.
.THU AND THU NIGHT...NW winds 5 to 10 kt. Seas 2 to 3 ft. Wave
Detail: SW 2 ft at 6 seconds and SE 2 ft at 8 seconds.
.FRI AND FRI NIGHT...E winds 5 to 10 kt. Seas 2 to 3 ft.
.SAT AND SAT NIGHT...E winds 5 to 10 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.
$$
ANZ281-181800-
Ocean Waters from Provincetown to Nantucket from 20 to 60 NM-
102 AM EDT Tue Aug 18 2026
.REST OF TONIGHT...SE winds 5 to 10 kt. Seas 4 to 6 ft. Wave
Detail: S 4 ft at 6 seconds and SE 1 foot at 9 seconds. Patchy
fog. A chance of showers. Vsby 1 NM or less.
.TUE...N winds 5 to 10 kt. Seas 4 to 6 ft. Wave Detail: SE 5 ft
at 8 seconds and S 4 ft at 7 seconds. Patchy fog in the morning
with vsby 1 NM or less.
.TUE NIGHT...NW winds 5 to 10 kt. Seas 3 to 5 ft. Wave Detail: SE
5 ft at 8 seconds and SW 3 ft at 7 seconds. Patchy fog. Vsby 1 NM
or less.
.WED...SW winds 5 to 10 kt. Seas 3 to 4 ft. Wave Detail: S 3 ft
at 7 seconds. Patchy fog in the morning with vsby 1 NM or less.
.WED NIGHT AND THU...SW winds 5 to 10 kt. Seas around 3 ft. Wave
Detail: S 3 ft at 7 seconds.
.THU NIGHT...SW winds around 5 kt. Seas around 3 ft. Wave Detail:
SE 2 ft at 9 seconds and SW 1 foot at 5 seconds. A chance of
showers.
.FRI THROUGH SAT NIGHT...SE winds 5 to 10 kt. Seas 2 to 3 ft. A
chance of showers.
Seas are reported as significant wave height, which is the
average of the highest third of the waves. Individual wave
heights may be more than twice the significant wave height.
$$
ANZ282-181800-
Ocean Waters from Marthas Vineyard to Nantucket from 25 to 60 NM-
102 AM EDT Tue Aug 18 2026
.REST OF TONIGHT...W winds around 5 kt. Seas 4 to 6 ft. Wave
Detail: S 4 ft at 7 seconds and E 1 foot at 8 seconds. Patchy
fog. Vsby 1 NM or less.
.TUE...NW winds 5 to 10 kt. Seas 4 to 5 ft. Wave Detail: S 4 ft
at 7 seconds and E 3 ft at 8 seconds. Patchy fog in the morning
with vsby 1 NM or less.
.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. Patchy fog after
midnight with vsby 1 NM or less.
.WED...SW winds 5 to 10 kt. Seas around 3 ft. Wave Detail: SE
3 ft at 8 seconds and S 2 ft at 7 seconds. Patchy fog in the
morning with vsby 1 NM or less.
.WED NIGHT AND THU...SW winds 5 to 10 kt. Seas around 3 ft. Wave
Detail: S 2 ft at 7 seconds.
.THU NIGHT...W winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: SE
2 ft at 9 seconds and SW 1 foot at 4 seconds. A chance of showers
and tstms.
.FRI...NE winds 5 to 10 kt. 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.
.SAT AND SAT NIGHT...E winds around 10 kt, becoming S. Seas 2 to
4 ft. Showers likely.
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.
$$
ANZ283-181800-
Ocean Waters from Montauk NY to Marthas Vineyard from 25 to 60 NM-
102 AM EDT Tue Aug 18 2026
.REST OF TONIGHT...NW winds 5 to 10 kt. Seas 4 to 5 ft. Wave
Detail: S 4 ft at 7 seconds and NE 1 foot at 5 seconds. Patchy
fog. Vsby 1 NM or less.
.TUE...NW winds 5 to 10 kt. Seas 3 to 4 ft. Wave Detail: S 4 ft
at 7 seconds and NE 2 ft at 5 seconds. Patchy fog in the morning
with vsby 1 NM or less.
.TUE NIGHT...W winds 5 to 10 kt. Seas 3 to 4 ft. Wave Detail: S
3 ft at 7 seconds and SE 2 ft at 9 seconds. Patchy fog after
midnight with vsby 1 NM or less.
.WED...SW winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: S 2 ft
at 7 seconds and SE 2 ft at 8 seconds. Patchy fog in the morning
with vsby 1 to 3 NM.
.WED NIGHT AND THU...SW winds 5 to 10 kt. Seas 2 to 3 ft. Wave
Detail: S 2 ft at 7 seconds.
.THU NIGHT...SW winds 5 to 10 kt, becoming NW after midnight.
Seas 2 to 3 ft. Wave Detail: SE 2 ft at 9 seconds and SW 1 foot
at 4 seconds. A chance of showers and tstms.
.FRI THROUGH SAT...E winds 10 to 15 kt. Seas 2 to 3 ft. A chance
of showers.
.SAT NIGHT...SE winds 10 to 15 kt. Seas 3 to 4 ft. Showers
likely.
Winds and seas higher in and near tstms.
Seas are reported as significant wave height, which is the
average of the highest third of the waves. Individual wave
heights may be more than twice the significant wave height.
$$
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