Coastal Waters Forecast
Issued by NWS Boston, MA

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FZUS51 KBOX 160804
CWFBOX

Coastal Waters Forecast for Massachusetts and Rhode Island
National Weather Service Boston/Norton MA
404 AM EDT Wed Jul 16 2025

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

ANZ200-162100-
404 AM EDT Wed Jul 16 2025

.Synopsis for Massachusetts and Rhode Island coastal waters...
Bermuda high pres will build into the region over the next few
days before a cold front crosses the waters Fri. High pres will
build over the waters Sat through early next week.

$$

ANZ250-162100-
Coastal waters east of Ipswich Bay and the Stellwagen Bank
National Marine Sanctuary-
404 AM EDT Wed Jul 16 2025

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

$$

ANZ251-162100-
Massachusetts Bay and Ipswich Bay-
404 AM EDT Wed Jul 16 2025

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

$$

ANZ231-162100-
Cape Cod Bay-
404 AM EDT Wed Jul 16 2025

.TODAY...SW winds around 5 kt, becoming S with gusts up to 20 kt
this afternoon. Seas 1 foot or less, then around 2 ft this
afternoon. Wave Detail: SW 1 foot at 2 seconds and SE 1 foot at
7 seconds. Patchy fog this morning with vsby 1 NM or less.
.TONIGHT...SW winds around 10 kt. Seas around 2 ft. Wave Detail:
SW 1 foot at 3 seconds and E 1 foot at 7 seconds. Patchy fog
after midnight with vsby 1 NM or less.
.THU...SW winds 10 to 15 kt with gusts up to 25 kt. Seas 2 to
4 ft. Wave Detail: SW 2 ft at 3 seconds and SE 1 foot at
7 seconds. Patchy fog in the morning with vsby 1 NM or less.
.THU NIGHT...SW winds 10 to 15 kt with gusts up to 25 kt. Seas
2 to 3 ft. Wave Detail: SW 2 ft at 3 seconds and SE 1 foot at
9 seconds.
.FRI AND FRI NIGHT...N winds 10 to 15 kt with gusts up to 20 kt.
Seas around 2 ft. Wave Detail: W 1 foot at 3 seconds and SE
1 foot at 9 seconds.
.SAT AND SAT NIGHT...NE winds 5 to 10 kt, becoming S. Seas around
2 ft, then 1 foot or less. Wave Detail: N 1 foot at 5 seconds and
SE 1 foot at 15 seconds, becoming SE 1 foot at 4 seconds and SE
1 foot at 15 seconds.
.SUN AND SUN NIGHT...S winds 10 to 15 kt with gusts up to 20 kt,
becoming W. 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.

$$

ANZ254-162100-
Coastal waters from Provincetown MA to Chatham MA to Nantucket MA
out 20 nm-
404 AM EDT Wed Jul 16 2025

.TODAY...SW winds 5 to 10 kt. Seas around 2 ft. Wave Detail: S
2 ft at 6 seconds. Patchy fog. Vsby 1 NM or less.
.TONIGHT...SW winds 10 to 15 kt. Seas 2 to 3 ft. Wave Detail: SE
2 ft at 6 seconds. Patchy fog. Vsby 1 NM or less.
.THU...SW winds 10 to 15 kt with gusts up to 25 kt. Seas 2 to
4 ft. Wave Detail: S 4 ft at 5 seconds and E 1 foot at 9 seconds.
Patchy fog. Vsby 1 NM or less, increasing to 1 to 3 NM in the
afternoon.
.THU NIGHT...SW winds 10 to 15 kt with gusts up to 25 kt. Seas
3 to 5 ft. Wave Detail: S 4 ft at 6 seconds and E 1 foot at
10 seconds. Patchy fog in the evening. Showers and tstms likely
in the evening with vsby 1 to 3 NM.
.FRI...W winds 10 to 15 kt, becoming N in the afternoon. Gusts up
to 20 kt. Seas 3 to 5 ft. Wave Detail: W 4 ft at 6 seconds and E
1 foot at 9 seconds.
.FRI NIGHT...N winds 5 to 10 kt. Seas 2 to 4 ft. Wave Detail: NW
3 ft at 6 seconds and E 2 ft at 10 seconds.
.SAT AND SAT NIGHT...E winds 5 to 10 kt, becoming S. Seas 2 to
3 ft.
.SUN AND SUN NIGHT...S winds 10 to 15 kt with gusts up to 20 kt,
becoming SW. 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.

$$

ANZ255-162100-
Coastal Waters extending out to 25 nm South of Marthas Vineyard
and Nantucket-
404 AM EDT Wed Jul 16 2025

.TODAY...SW winds 5 to 10 kt. Seas around 2 ft. Wave Detail: SW
2 ft at 5 seconds and E 1 foot at 7 seconds. Patchy fog. Vsby
1 NM or less.
.TONIGHT...SW winds 10 to 15 kt. Seas 2 to 3 ft. Wave Detail: S
3 ft at 5 seconds and E 1 foot at 7 seconds. Patchy fog. Vsby
1 NM or less.
.THU...SW winds 15 to 20 kt with gusts up to 25 kt. Seas 3 to
5 ft. Wave Detail: S 4 ft at 6 seconds and E 1 foot at 8 seconds.
Patchy fog in the morning with vsby 1 NM or less.
.THU NIGHT...SW winds 15 to 20 kt with gusts up to 25 kt. Seas
4 to 6 ft. Wave Detail: SW 5 ft at 6 seconds and E 1 foot at
10 seconds.
.FRI...NW winds 10 to 15 kt. Gusts up to 20 kt in the morning.
Seas 3 to 5 ft. Wave Detail: SW 5 ft at 7 seconds and E 1 foot at
10 seconds.
.FRI NIGHT...NE winds 10 to 15 kt. Seas 3 to 4 ft. Wave Detail:
SW 4 ft at 7 seconds and NE 1 foot at 9 seconds.
.SAT AND SAT NIGHT...E winds 5 to 10 kt, becoming S. Seas 2 to
3 ft.
.SUN...S winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to
3 ft. A chance of showers.
.SUN NIGHT...SW 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.

$$

ANZ256-162100-
Coastal Waters from Montauk NY to Marthas Vineyard extending out
to 20 nm South of Block Island-
404 AM EDT Wed Jul 16 2025

.TODAY...SW winds 5 to 10 kt. Seas around 2 ft. Wave Detail: SE
2 ft at 6 seconds. Patchy fog. Vsby 1 NM or less.
.TONIGHT...SW winds 10 to 15 kt. Seas 2 to 3 ft. Wave Detail: SE
3 ft at 6 seconds. Patchy fog. Vsby 1 NM or less.
.THU...SW winds 15 to 20 kt with gusts up to 25 kt. Seas 3 to
5 ft. Wave Detail: SE 4 ft at 7 seconds. Patchy fog in the
morning with vsby 1 to 3 NM.
.THU NIGHT...SW winds 15 to 20 kt with gusts up to 25 kt. Seas
4 to 5 ft. Wave Detail: S 5 ft at 6 seconds and E 1 foot at
10 seconds.
.FRI...W winds 10 to 15 kt. Gusts up to 20 kt in the morning.
Seas 3 to 5 ft. Wave Detail: SW 5 ft at 7 seconds and E 1 foot at
10 seconds.
.FRI NIGHT...NE winds 10 to 15 kt. Seas 3 to 4 ft. Wave Detail:
SW 4 ft at 7 seconds and NE 2 ft at 4 seconds.
.SAT AND SAT NIGHT...E winds around 10 kt, becoming S. Seas 2 to
3 ft.
.SUN...S winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to
3 ft. A chance of showers.
.SUN NIGHT...W winds 10 to 15 kt. Seas around 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.

$$

ANZ232-162100-
Nantucket Sound-
404 AM EDT Wed Jul 16 2025

.TODAY...SW winds 5 to 10 kt. Seas 1 foot or less, then around
2 ft this afternoon. Wave Detail: SW 1 foot at 3 seconds and SE
1 foot at 6 seconds, becoming SW 1 foot at 3 seconds and E 1 foot
at 6 seconds. Patchy fog. Vsby 1 NM or less.
.TONIGHT...SW winds 10 to 15 kt. Seas around 2 ft. Wave Detail:
SW 2 ft at 3 seconds and E 1 foot at 6 seconds. Patchy fog. Vsby
1 to 3 NM, decreasing to 1 NM or less after midnight.
.THU...SW winds 10 to 15 kt, increasing to 15 to 20 kt in the
afternoon. Gusts up to 25 kt. Seas 2 to 3 ft. Wave Detail: SW
3 ft at 4 seconds and SE 1 foot at 7 seconds. Patchy fog in the
morning with vsby 1 to 3 NM.
.THU NIGHT...SW winds 15 to 20 kt with gusts up to 25 kt. Seas
2 to 3 ft. Wave Detail: SW 3 ft at 4 seconds and SE 1 foot at
9 seconds.
.FRI AND FRI NIGHT...N winds 10 to 15 kt with gusts up to 20 kt.
Seas 2 to 3 ft. Wave Detail: W 2 ft at 4 seconds and SE 1 foot at
10 seconds.
.SAT AND SAT NIGHT...E winds around 10 kt, becoming S. Seas
around 2 ft. Wave Detail: NE 1 foot at 3 seconds and SW 1 foot at
7 seconds.
.SUN AND SUN NIGHT...S winds 10 to 15 kt with gusts up to 20 kt,
becoming W. 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.

$$

ANZ233-162100-
Vineyard Sound-
404 AM EDT Wed Jul 16 2025

.TODAY...SW winds 5 to 10 kt. Seas 1 foot or less, then around
2 ft this afternoon. Wave Detail: SW 1 foot at 4 seconds and SE
1 foot at 7 seconds, becoming SW 1 foot at 4 seconds and SE
1 foot at 8 seconds. Patchy fog. Vsby 1 NM or less.
.TONIGHT...SW winds 10 to 15 kt. Seas around 2 ft. Wave Detail:
SW 2 ft at 4 seconds and SE 1 foot at 8 seconds. Patchy fog. Vsby
1 to 3 NM, decreasing to 1 NM or less after midnight.
.THU...SW winds 10 to 15 kt, increasing to 15 to 20 kt in the
afternoon. Gusts up to 25 kt. Seas 2 to 4 ft. Wave Detail: SW
3 ft at 5 seconds and E 1 foot at 8 seconds. Patchy fog in the
morning with vsby 1 to 3 NM.
.THU NIGHT...SW winds 15 to 20 kt, diminishing to 10 to 15 kt
after midnight. Seas 2 to 4 ft. Wave Detail: SW 3 ft at 5 seconds
and E 1 foot at 8 seconds.
.FRI...NW winds 10 to 15 kt. Seas 2 to 3 ft. Wave Detail: SW 3 ft
at 6 seconds and E 1 foot at 10 seconds.
.FRI NIGHT...NE winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: SW
2 ft at 7 seconds and NE 1 foot at 6 seconds.
.SAT AND SAT NIGHT...E winds around 10 kt, becoming S. Seas
around 2 ft.
.SUN AND SUN NIGHT...S winds 10 to 15 kt with gusts up to 20 kt,
becoming W. 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.

$$

ANZ234-162100-
Buzzards Bay-
404 AM EDT Wed Jul 16 2025

.TODAY...SW winds 5 to 10 kt. Gusts up to 20 kt this afternoon.
Seas 1 foot or less, then around 2 ft this afternoon. Wave
Detail: SW 1 foot at 3 seconds and SE 1 foot at 7 seconds. Patchy
fog. Vsby 1 NM or less, increasing to 1 to 3 NM this afternoon.
.TONIGHT...SW winds around 10 kt. Seas around 2 ft. Wave Detail:
SW 1 foot at 3 seconds and SE 1 foot at 7 seconds. Patchy fog.
Vsby 1 to 3 NM, decreasing to 1 NM or less after midnight.
.THU...SW winds 10 to 15 kt, increasing to 15 to 20 kt in the
afternoon. Gusts up to 25 kt. Seas 2 to 4 ft. Wave Detail: SW
3 ft at 4 seconds and SE 1 foot at 7 seconds. Patchy fog in the
morning with vsby 1 to 3 NM.
.THU NIGHT...SW winds 15 to 20 kt, diminishing to 10 to 15 kt
after midnight. Gusts up to 25 kt. Seas 2 to 4 ft. Wave Detail:
SW 3 ft at 5 seconds and SE 1 foot at 9 seconds.
.FRI...NW winds 10 to 15 kt. Gusts up to 20 kt in the afternoon.
Seas 2 to 3 ft. Wave Detail: SW 2 ft at 7 seconds and SE 1 foot
at 9 seconds.
.FRI NIGHT...NE winds 5 to 10 kt. Seas around 2 ft. Wave Detail:
SW 2 ft at 7 seconds and NE 1 foot at 5 seconds.
.SAT AND SAT NIGHT...E winds 5 to 10 kt, becoming S. Seas around
2 ft.
.SUN AND SUN NIGHT...SW winds 10 to 15 kt with gusts up to 20 kt,
becoming W. 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.

$$

ANZ235-162100-
Rhode Island Sound-
404 AM EDT Wed Jul 16 2025

.TODAY...SW winds 5 to 10 kt. Seas around 2 ft. Wave Detail: S
2 ft at 5 seconds and SE 1 foot at 8 seconds. Patchy fog. Vsby
1 NM or less.
.TONIGHT...SW winds 10 to 15 kt. Seas 2 to 3 ft. Wave Detail: S
3 ft at 7 seconds. Patchy fog. Vsby 1 to 3 NM, decreasing to 1 NM
or less after midnight.
.THU...SW winds 10 to 15 kt, increasing to 15 to 20 kt in the
afternoon. Gusts up to 25 kt. Seas 2 to 4 ft. Wave Detail: S 4 ft
at 6 seconds and SE 1 foot at 9 seconds. Patchy fog in the
morning with vsby 1 to 3 NM.
.THU NIGHT...SW winds 15 to 20 kt with gusts up to 25 kt. Seas
3 to 4 ft. Wave Detail: S 4 ft at 6 seconds and SE 1 foot at
9 seconds.
.FRI...W winds 10 to 15 kt. Seas 3 to 4 ft. Wave Detail: SW 4 ft
at 7 seconds and SE 1 foot at 10 seconds.
.FRI NIGHT...NE winds around 10 kt. Seas 2 to 3 ft. Wave Detail:
S 3 ft at 7 seconds and E 1 foot at 8 seconds.
.SAT AND SAT NIGHT...E winds around 10 kt, becoming S. Seas 2 to
3 ft.
.SUN AND SUN NIGHT...S winds 10 to 15 kt with gusts up to 20 kt,
becoming W. 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.

$$

ANZ237-162100-
Block Island Sound-
404 AM EDT Wed Jul 16 2025

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

$$

ANZ230-162100-
Boston Harbor-
404 AM EDT Wed Jul 16 2025

.TODAY...S winds 5 to 10 kt. Waves 1 foot or less, then around
2 ft this afternoon.
.TONIGHT...S winds 10 to 15 kt. Waves around 2 ft in the evening,
then 1 foot or less. Patchy fog after midnight with vsby 1 to
3 NM.
.THU...SW winds 10 to 15 kt. Gusts up to 20 kt in the afternoon.
Waves around 2 ft. A chance of showers.
.THU NIGHT...SW winds 10 to 15 kt. Gusts up to 20 kt in the
evening. Waves around 2 ft. A chance of showers in the evening.
.FRI AND FRI NIGHT...N winds 10 to 15 kt. Waves around 2 ft.
.SAT AND SAT NIGHT...E winds 5 to 10 kt, becoming S. Waves around
2 ft.
.SUN AND SUN NIGHT...SW winds 10 to 15 kt, becoming W. Waves
around 2 ft. A chance of showers.

Seas are reported as significant wave height, which is the
average of the highest third of the waves. Individual wave
heights may be more than twice the significant wave height.

$$

ANZ236-162100-
Narragansett Bay-
404 AM EDT Wed Jul 16 2025

.TODAY...S winds 5 to 10 kt. Waves 1 foot or less, then around
2 ft this afternoon. Patchy fog this morning with vsby 1 NM or
less.
.TONIGHT...SW winds around 10 kt. Waves around 2 ft. Patchy fog.
Vsby 1 to 3 NM.
.THU...SW winds 10 to 15 kt with gusts up to 20 kt. Waves 2 to
3 ft. A chance of showers in the morning.
.THU NIGHT...SW winds 10 to 15 kt. Gusts up to 20 kt in the
evening. Waves 2 to 3 ft.
.FRI...NW winds around 10 kt. Waves 2 to 3 ft.
.FRI NIGHT...N winds 5 to 10 kt. Waves around 2 ft.
.SAT AND SAT NIGHT...E winds 5 to 10 kt, becoming S. Waves around
2 ft.
.SUN AND SUN NIGHT...S winds 5 to 10 kt, becoming W. 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.

$$

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