Coastal Waters Forecast
Issued by NWS Boston, MA

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591
FZUS51 KBOX 260203
CWFBOX

Coastal Waters Forecast for Massachusetts and Rhode Island
National Weather Service Boston/Norton MA
1003 PM EDT Fri Jul 25 2025

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

ANZ200-261500-
1003 PM EDT Fri Jul 25 2025

.Synopsis for Massachusetts and Rhode Island coastal waters...
High pressure moves offshore Friday morning, a cold front will move
into New England during the afternoon, crossing the waters overnight
into Saturday morning. Low pressure system crosses the waters Monday.

$$

ANZ250-261500-
Coastal waters east of Ipswich Bay and the Stellwagen Bank
National Marine Sanctuary-
1003 PM EDT Fri Jul 25 2025

.OVERNIGHT...N winds 10 to 15 kt with gusts up to 20 kt. Seas
2 to 3 ft. Wave Detail: NW 2 ft at 4 seconds and SE 1 foot at
9 seconds. Patchy fog. A slight chance of tstms. Some tstms may
be severe with gusty winds, small hail, frequent lightning, and
heavy rainfall. Vsby 1 to 3 NM.
.SAT...N winds 10 to 15 kt with gusts up to 20 kt, becoming E
5 to 10 kt in the afternoon. Seas 2 to 3 ft. Wave Detail: N 3 ft
at 9 seconds and NW 2 ft at 3 seconds.
.SAT NIGHT...S winds 5 to 10 kt. Seas around 2 ft. Wave Detail:
NE 2 ft at 6 seconds and S 1 foot at 2 seconds.
.SUN...S winds 10 to 15 kt. Gusts up to 20 kt in the afternoon.
Seas 2 to 3 ft. Wave Detail: S 2 ft at 3 seconds and E 1 foot at
7 seconds.
.SUN NIGHT THROUGH MON NIGHT...SW 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 8 seconds.
.TUE THROUGH WED...N winds 10 to 15 kt with gusts up to 20 kt.
Seas 2 to 3 ft. Wave Detail: SW 2 ft at 3 seconds and E 1 foot at
8 seconds.
.WED NIGHT...W winds around 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.

$$

ANZ251-261500-
Massachusetts Bay and Ipswich Bay-
1003 PM EDT Fri Jul 25 2025

.OVERNIGHT...N winds 10 to 15 kt. Gusts up to 20 kt. Seas around
2 ft. Wave Detail: NW 1 foot at 3 seconds and SE 1 foot at
9 seconds.
.SAT...N winds 5 to 10 kt, becoming E in the afternoon. Seas
around 2 ft. Wave Detail: N 2 ft at 4 seconds.
.SAT NIGHT...S winds 5 to 10 kt. Seas 1 foot or less. Wave
Detail: S 1 foot at 2 seconds and NE 1 foot at 5 seconds.
.SUN...S winds 5 to 10 kt, increasing to 10 to 15 kt with gusts
up to 20 kt in the afternoon. Seas 1 foot or less, then around
2 ft in the afternoon. Wave Detail: S 1 foot at 2 seconds and E
1 foot at 6 seconds, becoming S 2 ft at 3 seconds and E 1 foot at
8 seconds.
.SUN NIGHT...S winds 10 to 15 kt with gusts up to 20 kt, becoming
SW 5 to 10 kt after midnight. Seas around 2 ft. Wave Detail: S
2 ft at 3 seconds and E 1 foot at 8 seconds.
.MON AND MON NIGHT...SW winds 10 to 15 kt. Seas around 2 ft. Wave
Detail: SE 2 ft at 3 seconds and E 1 foot at 8 seconds.
.TUE THROUGH WED...NE winds 10 to 15 kt with gusts up to 20 kt.
Seas around 2 ft.
.WED NIGHT...W winds around 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.

$$

ANZ231-261500-
Cape Cod Bay-
1003 PM EDT Fri Jul 25 2025

.OVERNIGHT...NW winds 5 to 10 kt, becoming N 10 to 15 kt with
gusts up to 20 kt. Seas around 2 ft. Wave Detail: W 1 foot at
2 seconds and SE 1 foot at 9 seconds. Patchy fog. A slight chance
of showers and tstms. Some tstms may be severe with gusty winds,
small hail, frequent lightning, and heavy rainfall. Vsby 1 to
3 NM.
.SAT...NE winds 10 to 15 kt with gusts up to 20 kt, diminishing
to 5 to 10 kt in the afternoon. Seas around 2 ft. Wave Detail: N
1 foot at 4 seconds.
.SAT NIGHT...S winds around 5 kt. Seas 1 foot or less. Wave
Detail: E 1 foot at 4 seconds.
.SUN...S winds 5 to 10 kt. Seas 1 foot or less, then around 2 ft
in the afternoon. Wave Detail: S 1 foot at 2 seconds and NE
1 foot at 5 seconds.
.SUN NIGHT AND MON...S winds 5 to 10 kt. Seas around 2 ft. Wave
Detail: S 1 foot at 2 seconds and E 1 foot at 6 seconds.
.MON NIGHT...SW winds around 10 kt. Seas around 2 ft. Wave
Detail: S 1 foot at 2 seconds and E 1 foot at 8 seconds.
.TUE THROUGH WED NIGHT...W winds 10 to 15 kt with gusts up to
20 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.

$$

ANZ254-261500-
Coastal waters from Provincetown MA to Chatham MA to Nantucket MA
out 20 nm-
1003 PM EDT Fri Jul 25 2025

.OVERNIGHT...NW winds around 10 kt, becoming N with gusts up to
20 kt. Seas 2 to 3 ft. Wave Detail: NW 3 ft at 4 seconds and SE
1 foot at 9 seconds. Patchy fog. A chance of showers and tstms.
Some tstms may be severe with gusty winds, small hail, frequent
lightning, and heavy rainfall. Vsby 1 NM or less, increasing to
1 to 3 NM.
.SAT...NE winds 10 to 15 kt. Gusts up to 20 kt in the morning.
Seas 2 to 3 ft. Wave Detail: N 3 ft at 5 seconds and S 3 ft at
6 seconds.
.SAT NIGHT...SE winds 5 to 10 kt, becoming S after midnight. Seas
2 to 3 ft. Wave Detail: NW 2 ft at 5 seconds and NE 2 ft at
6 seconds.
.SUN...S winds 5 to 10 kt. Seas around 2 ft. Wave Detail: NE 2 ft
at 6 seconds and SW 1 foot at 5 seconds.
.SUN NIGHT THROUGH MON NIGHT...SW winds 5 to 10 kt. Seas around
2 ft. Wave Detail: SW 2 ft at 3 seconds and SE 1 foot at
7 seconds.
.TUE THROUGH WED NIGHT...W 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 8 seconds.

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.

$$

ANZ255-261500-
Coastal Waters extending out to 25 nm South of Marthas Vineyard
and Nantucket-
1003 PM EDT Fri Jul 25 2025

.OVERNIGHT...W winds around 10 kt, becoming N with gusts up to
20 kt. Seas 2 to 3 ft. Wave Detail: SW 3 ft at 6 seconds and SE
2 ft at 9 seconds. Patchy fog. A slight chance of showers and
tstms. Some tstms may be severe with gusty winds, small hail,
frequent lightning, and heavy rainfall. Vsby 1 to 3 NM.
.SAT...NE winds 10 to 15 kt. Gusts up to 20 kt in the morning.
Seas 2 to 3 ft. Wave Detail: NE 3 ft at 4 seconds and SW 3 ft at
5 seconds.
.SAT NIGHT...E winds 5 to 10 kt, becoming S after midnight. Seas
2 to 3 ft. Wave Detail: E 2 ft at 6 seconds and S 1 foot at
5 seconds.
.SUN...S winds 5 to 10 kt. Seas around 2 ft. Wave Detail: SE 2 ft
at 6 seconds.
.SUN NIGHT AND MON...S winds around 10 kt. Seas around 2 ft. Wave
Detail: S 2 ft at 3 seconds and SE 2 ft at 7 seconds.
.MON NIGHT...S winds around 10 kt. Seas around 2 ft. Wave Detail:
S 2 ft at 4 seconds and SE 1 foot at 8 seconds.
.TUE THROUGH WED NIGHT...W winds 10 to 15 kt with gusts up to
20 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.

$$

ANZ256-261500-
Coastal Waters from Montauk NY to Marthas Vineyard extending out
to 20 nm South of Block Island-
1003 PM EDT Fri Jul 25 2025

.OVERNIGHT...W winds around 10 kt, becoming N with gusts up to
20 kt. Seas around 3 ft. Wave Detail: SW 3 ft at 5 seconds and SE
2 ft at 9 seconds.
.SAT...NE winds 10 to 15 kt. Gusts up to 20 kt in the morning.
Seas 2 to 3 ft. Wave Detail: NE 3 ft at 5 seconds and SW 2 ft at
5 seconds.
.SAT NIGHT...SE winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: SE
2 ft at 5 seconds.
.SUN...S winds 5 to 10 kt. Seas around 2 ft. Wave Detail: S 2 ft
at 3 seconds and SE 2 ft at 8 seconds. A chance of showers in the
afternoon.
.SUN NIGHT...S winds around 10 kt, becoming SW after midnight.
Seas around 2 ft. Wave Detail: S 2 ft at 3 seconds and SE 2 ft at
8 seconds. A chance of showers in the evening.
.MON AND MON NIGHT...SW winds around 10 kt. Seas around 2 ft.
Wave Detail: W 2 ft at 4 seconds and E 2 ft at 8 seconds.
.TUE THROUGH WED NIGHT...W winds 10 to 15 kt with gusts up to
20 kt. Seas 2 to 3 ft.

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

$$

ANZ232-261500-
Nantucket Sound-
1003 PM EDT Fri Jul 25 2025

.OVERNIGHT...NW winds around 10 kt, becoming N with gusts up to
20 kt. Seas around 2 ft. Wave Detail: NW 2 ft at 4 seconds and SE
1 foot at 9 seconds. Patchy fog. A slight chance of tstms. Some
tstms may be severe with gusty winds, small hail, frequent
lightning, and heavy rainfall.
.SAT...NE winds 10 to 15 kt. Gusts up to 20 kt in the morning.
Seas around 2 ft. Wave Detail: NE 2 ft at 3 seconds and SW 1 foot
at 5 seconds.
.SAT NIGHT...SE winds 5 to 10 kt, becoming S after midnight. Seas
around 2 ft in the evening, then 1 foot or less. Wave Detail: E
1 foot at 6 seconds, becoming S 1 foot at 4 seconds and E 1 foot
at 6 seconds.
.SUN...S winds 5 to 10 kt. Seas 1 foot or less, then around 2 ft
in the afternoon. Wave Detail: S 1 foot at 3 seconds and E 1 foot
at 6 seconds.
.SUN NIGHT THROUGH MON NIGHT...SW winds around 10 kt. Seas around
2 ft. Wave Detail: S 1 foot at 3 seconds and E 1 foot at
7 seconds.
.TUE THROUGH WED NIGHT...W winds 10 to 15 kt with gusts up to
20 kt. Seas around 2 ft. Wave Detail: SW 2 ft at 3 seconds and E
1 foot at 8 seconds.

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.

$$

ANZ233-261500-
Vineyard Sound-
1003 PM EDT Fri Jul 25 2025

.OVERNIGHT...NW winds 5 to 10 kt, becoming N 10 to 15 kt with
gusts up to 20 kt. Seas around 2 ft. Wave Detail: SW 2 ft at
5 seconds and SE 1 foot at 9 seconds.
.SAT...NE winds 10 to 15 kt. Gusts up to 20 kt in the morning.
Seas around 2 ft. Wave Detail: NE 1 foot at 3 seconds and SW
1 foot at 5 seconds.
.SAT NIGHT...S winds 5 to 10 kt. Seas around 2 ft in the evening,
then 1 foot or less. Wave Detail: SE 1 foot at 6 seconds,
becoming S 1 foot at 4 seconds and SE 1 foot at 7 seconds.
.SUN...S winds 5 to 10 kt. Seas 1 foot or less, then around 2 ft
in the afternoon. Wave Detail: S 1 foot at 3 seconds and SE
1 foot at 7 seconds.
.SUN NIGHT THROUGH MON NIGHT...SW winds 5 to 10 kt. Seas around
2 ft. Wave Detail: S 1 foot at 3 seconds and SE 1 foot at
8 seconds.
.TUE THROUGH WED NIGHT...W winds 10 to 15 kt with gusts up to
20 kt. Seas around 2 ft. Wave Detail: SW 2 ft at 4 seconds and SE
1 foot at 9 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.

$$

ANZ234-261500-
Buzzards Bay-
1003 PM EDT Fri Jul 25 2025

.OVERNIGHT...NW winds 5 to 10 kt, becoming N 10 to 15 kt with
gusts up to 20 kt. Seas around 2 ft. Wave Detail: SW 2 ft at
5 seconds and SE 1 foot at 9 seconds.
.SAT...NE winds 10 to 15 kt with gusts up to 20 kt, becoming E in
the afternoon. Seas around 2 ft. Wave Detail: NE 1 foot at
3 seconds and SW 1 foot at 5 seconds.
.SAT NIGHT...S winds 5 to 10 kt. Seas 1 foot or less. Wave
Detail: E 1 foot at 5 seconds.
.SUN...S winds 5 to 10 kt. Seas 1 foot or less, then around 2 ft
in the afternoon. Wave Detail: S 1 foot at 3 seconds and SE
1 foot at 7 seconds.
.SUN NIGHT THROUGH MON NIGHT...SW winds 5 to 10 kt. Seas around
2 ft. Wave Detail: S 1 foot at 3 seconds and SE 1 foot at
8 seconds.
.TUE THROUGH WED NIGHT...W winds 10 to 15 kt with gusts up to
20 kt. Seas 2 to 3 ft. Wave Detail: SW 2 ft at 3 seconds and SE
1 foot at 8 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.

$$

ANZ235-261500-
Rhode Island Sound-
1003 PM EDT Fri Jul 25 2025

.OVERNIGHT...NW winds around 10 kt, becoming N with gusts up to
20 kt. Seas 2 to 3 ft. Wave Detail: SW 3 ft at 5 seconds and SE
1 foot at 9 seconds.
.SAT...NE winds 10 to 15 kt with gusts up to 20 kt, becoming E in
the afternoon. Seas 2 to 3 ft. Wave Detail: NE 2 ft at 4 seconds
and S 2 ft at 6 seconds.
.SAT NIGHT...S winds 5 to 10 kt. Seas around 2 ft. Wave Detail:
SE 2 ft at 6 seconds.
.SUN...S winds 5 to 10 kt. Seas 1 foot or less, then around 2 ft
in the afternoon. Wave Detail: SE 1 foot at 4 seconds and SE
1 foot at 8 seconds, becoming S 2 ft at 3 seconds and SE 1 foot
at 8 seconds. A chance of showers in the afternoon.
.SUN NIGHT...S winds around 10 kt, becoming SW after midnight.
Seas around 2 ft. Wave Detail: S 2 ft at 4 seconds and SE 1 foot
at 8 seconds. A chance of showers in the evening.
.MON AND MON NIGHT...SW winds 5 to 10 kt. Seas around 2 ft. Wave
Detail: S 2 ft at 4 seconds and SE 1 foot at 8 seconds.
.TUE THROUGH WED NIGHT...W winds 10 to 15 kt with gusts up to
20 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.

$$

ANZ237-261500-
Block Island Sound-
1003 PM EDT Fri Jul 25 2025

.OVERNIGHT...NW winds 5 to 10 kt, becoming N 10 to 15 kt. Seas
around 2 ft. Wave Detail: W 2 ft at 5 seconds and SE 1 foot at
9 seconds.
.SAT...NE winds 10 to 15 kt with gusts up to 20 kt, becoming E in
the afternoon. Seas 2 to 3 ft. Wave Detail: NE 2 ft at 5 seconds
and S 2 ft at 6 seconds.
.SAT NIGHT...S winds 5 to 10 kt. Seas around 2 ft. Wave Detail:
SE 2 ft at 6 seconds.
.SUN...S winds 5 to 10 kt. Seas around 2 ft. Wave Detail: SE
1 foot at 4 seconds and SE 1 foot at 7 seconds. A chance of
showers in the afternoon.
.SUN NIGHT...S winds 5 to 10 kt, becoming W after midnight. Seas
around 2 ft. Wave Detail: S 2 ft at 3 seconds and SE 1 foot at
8 seconds. A chance of showers in the evening.
.MON AND MON NIGHT...SW winds 5 to 10 kt. Seas around 2 ft. Wave
Detail: W 1 foot at 4 seconds and SE 1 foot at 8 seconds.
.TUE THROUGH WED...SW winds 10 to 15 kt with gusts up to 20 kt.
Seas around 2 ft.
.WED NIGHT...W winds around 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.

$$

ANZ230-261500-
Boston Harbor-
1003 PM EDT Fri Jul 25 2025

.OVERNIGHT...N winds around 10 kt. Waves around 2 ft, then 1 foot
or less.
.SAT...NE winds 5 to 10 kt, becoming E in the afternoon. Waves
1 foot or less.
.SAT NIGHT...S winds 5 to 10 kt, becoming SW after midnight.
Waves 1 foot or less.
.SUN...SW winds 5 to 10 kt, becoming S 10 to 15 kt in the
afternoon. Waves 1 foot or less, then around 2 ft in the
afternoon. A chance of showers in the afternoon.
.SUN NIGHT...S winds 10 to 15 kt, becoming SW 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.
.MON AND MON NIGHT...SW winds 5 to 10 kt. Waves around 2 ft.
.TUE THROUGH WED...E winds 5 to 10 kt. Waves around 2 ft.
.WED NIGHT...W 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.

$$

ANZ236-261500-
Narragansett Bay-
1003 PM EDT Fri Jul 25 2025

.OVERNIGHT...N winds 5 to 10 kt. Waves around 2 ft.
.SAT...NE winds 10 to 15 kt, becoming E 5 to 10 kt in the
afternoon. Waves around 2 ft.
.SAT NIGHT...S winds 5 to 10 kt. Waves around 2 ft in the
evening, then 1 foot or less.
.SUN...S winds 5 to 10 kt. Waves 1 foot or less, then around 2 ft
in the afternoon. A chance of showers in the afternoon.
.SUN NIGHT...S winds 5 to 10 kt, becoming SW after midnight.
Waves around 2 ft in the evening, then 1 foot or less. A chance
of showers in the evening.
.MON AND MON NIGHT...SW winds 5 to 10 kt. Waves around 2 ft.
.TUE THROUGH WED...W winds 10 to 15 kt with gusts up to 20 kt.
Waves around 2 ft.
.WED NIGHT...W 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.

$$

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