Coastal Waters Forecast
Issued by NWS Boston, MA

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FZUS51 KBOX 041703
CWFBOX

Coastal Waters Forecast for Massachusetts and Rhode Island
National Weather Service Boston/Norton MA
102 PM EDT Sat Oct 4 2025

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

ANZ200-050600-
102 PM EDT Sat Oct 4 2025

.Synopsis for Massachusetts and Rhode Island coastal waters...
High pres remains anchored over the waters south of Southern New
England through early next week. Mainly light west winds are
expected through the weekend, then SW winds pick up for early next
week.

$$

ANZ250-050600-
Coastal waters east of Ipswich Bay and the Stellwagen Bank
National Marine Sanctuary-
102 PM EDT Sat Oct 4 2025

.THIS AFTERNOON...SW winds 5 to 10 kt. Seas 2 to 3 ft. Wave
Detail: E 3 ft at 11 seconds and W 1 foot at 3 seconds.
.TONIGHT...SW winds 5 to 10 kt, becoming NW after midnight. Seas
2 to 3 ft. Wave Detail: E 2 ft at 12 seconds and SW 1 foot at
3 seconds.
.SUN...NE winds around 5 kt, becoming SE around 5 kt in the
afternoon. Seas 2 to 3 ft. Wave Detail: E 2 ft at 13 seconds and
NW 1 foot at 2 seconds. Patchy fog in the afternoon with vsby
1 NM or less.
.SUN NIGHT...S winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: SW
2 ft at 3 seconds and E 2 ft at 12 seconds.
.MON AND MON NIGHT...SW winds 10 to 15 kt with gusts up to 20 kt.
Seas 2 to 3 ft. Wave Detail: SW 3 ft at 4 seconds and E 2 ft at
11 seconds.
.TUE...SW winds 15 to 20 kt with gusts up to 25 kt. Seas 2 to
4 ft. Wave Detail: SW 3 ft at 4 seconds and E 1 foot at
10 seconds.
.TUE NIGHT AND WED...SW winds 15 to 20 kt, becoming W. Gusts up
to 30 kt. Seas 2 to 4 ft. Showers. Vsby 1 to 3 NM.
.WED NIGHT...N winds 15 to 20 kt with gusts up to 25 kt. Seas
3 to 5 ft. A chance of showers. Vsby 1 to 3 NM.

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.

$$

ANZ251-050600-
Massachusetts Bay and Ipswich Bay-
102 PM EDT Sat Oct 4 2025

.THIS AFTERNOON...S winds 5 to 10 kt. Seas around 2 ft. Wave
Detail: E 2 ft at 10 seconds and W 1 foot at 3 seconds.
.TONIGHT...SW winds 5 to 10 kt, becoming NW after midnight. Seas
around 2 ft. Wave Detail: E 2 ft at 12 seconds and S 1 foot at
2 seconds.
.SUN...N winds around 5 kt, becoming E in the afternoon. Seas
around 2 ft. Wave Detail: E 2 ft at 11 seconds.
.SUN NIGHT...S winds 5 to 10 kt. Seas around 2 ft. Wave Detail: E
2 ft at 12 seconds and S 1 foot at 3 seconds.
.MON AND 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 E 2 ft at
11 seconds.
.TUE...SW winds 15 to 20 kt with gusts up to 25 kt. Seas 2 to
3 ft. Wave Detail: SW 3 ft at 3 seconds and E 1 foot at
10 seconds.
.TUE NIGHT AND WED...SW winds 15 to 20 kt, becoming W 10 to
15 kt. Gusts up to 25 kt. Seas 2 to 3 ft. Showers likely. Vsby
1 to 3 NM.
.WED NIGHT...N winds 15 to 20 kt with gusts up to 25 kt. Seas
2 to 3 ft. A chance of showers. Vsby 1 to 3 NM.

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.

$$

ANZ231-050600-
Cape Cod Bay-
102 PM EDT Sat Oct 4 2025

.THIS AFTERNOON...SW winds around 5 kt. Seas around 2 ft. Wave
Detail: E 2 ft at 10 seconds and NW 1 foot at 3 seconds.
.TONIGHT...SW winds around 5 kt. Seas around 2 ft. Wave Detail: E
2 ft at 11 seconds and W 1 foot at 3 seconds.
.SUN...NW winds around 5 kt, becoming S around 5 kt in the
afternoon. Seas around 2 ft. Wave Detail: E 2 ft at 12 seconds
and W 1 foot at 2 seconds.
.SUN NIGHT...S winds 5 to 10 kt. Seas around 2 ft. Wave Detail: S
1 foot at 2 seconds and E 1 foot at 12 seconds.
.MON AND MON NIGHT...SW winds 10 to 15 kt with gusts up to 20 kt.
Seas around 2 ft. Wave Detail: SW 1 foot at 2 seconds and E
1 foot at 8 seconds.
.TUE...SW winds 15 to 20 kt with gusts up to 25 kt. Seas 2 to
4 ft. Wave Detail: SW 2 ft at 3 seconds and E 1 foot at
10 seconds.
.TUE NIGHT THROUGH WED NIGHT...N winds 15 to 20 kt with gusts up
to 25 kt. Seas 2 to 4 ft. Showers. Vsby 1 to 3 NM.

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.

$$

ANZ254-050600-
Coastal waters from Provincetown MA to Chatham MA to Nantucket MA
out 20 nm-
102 PM EDT Sat Oct 4 2025

.THIS AFTERNOON...W winds 5 to 10 kt. Seas 2 to 4 ft. Wave
Detail: E 3 ft at 12 seconds and W 2 ft at 4 seconds.
.TONIGHT...SW winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: E
3 ft at 12 seconds and SW 1 foot at 3 seconds.
.SUN...S winds around 5 kt. Seas 2 to 3 ft. Wave Detail: SE 3 ft
at 14 seconds and SW 1 foot at 3 seconds.
.SUN NIGHT...SW winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: E
3 ft at 13 seconds and SW 1 foot at 3 seconds. Patchy fog. Vsby
1 NM or less, increasing to 1 to 3 NM after midnight.
.MON...SW winds 5 to 10 kt, increasing to 10 to 15 kt with gusts
up to 20 kt in the afternoon. Seas 2 to 3 ft. Wave Detail: SW
2 ft at 3 seconds and E 2 ft at 11 seconds. Patchy fog in the
morning with vsby 1 to 3 NM.
.MON NIGHT...SW winds 10 to 15 kt with gusts up to 20 kt. Seas
2 to 3 ft. Wave Detail: SW 2 ft at 4 seconds and E 2 ft at
10 seconds.
.TUE...SW winds 10 to 15 kt with gusts up to 25 kt. Seas 2 to
3 ft.
.TUE NIGHT...SW winds 15 to 20 kt with gusts up to 25 kt. Seas
3 to 4 ft. A chance of showers. Vsby 1 to 3 NM.
.WED AND WED NIGHT...W winds around 15 kt, becoming N 20 to
25 kt. Seas 3 to 5 ft. Showers. Vsby 1 to 3 NM.

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.

$$

ANZ255-050600-
Coastal Waters extending out to 25 nm South of Marthas Vineyard
and Nantucket-
102 PM EDT Sat Oct 4 2025

.THIS AFTERNOON...W winds around 10 kt. Seas 3 to 4 ft. Wave
Detail: E 3 ft at 10 seconds and SW 2 ft at 5 seconds.
.TONIGHT...W winds 5 to 10 kt. Seas 2 to 4 ft. Wave Detail: E
3 ft at 12 seconds and SW 2 ft at 5 seconds.
.SUN...SW winds around 5 kt. Seas 2 to 3 ft. Wave Detail: SE 2 ft
at 12 seconds and SW 1 foot at 4 seconds. Patchy fog. Vsby 1 NM
or less.
.SUN NIGHT...SW winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: E
2 ft at 13 seconds and SW 1 foot at 4 seconds. Patchy fog. Vsby
1 NM or less, increasing to 1 to 3 NM after midnight.
.MON...SW winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: SW 2 ft
at 3 seconds and E 2 ft at 11 seconds. Patchy fog in the morning
with vsby 1 to 3 NM.
.MON NIGHT...SW winds 10 to 15 kt. Seas 2 to 3 ft. Wave Detail:
SW 2 ft at 4 seconds and E 2 ft at 10 seconds.
.TUE...SW winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to
3 ft.
.TUE NIGHT...SW winds 15 to 20 kt with gusts up to 25 kt. Seas
3 to 5 ft. A chance of showers. Vsby 1 to 3 NM.
.WED AND WED NIGHT...W winds 15 to 20 kt, becoming N 25 to 30 kt.
Seas 3 to 5 ft. Showers. Vsby 1 to 3 NM.

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.

$$

ANZ256-050600-
Coastal Waters from Montauk NY to Marthas Vineyard extending out
to 20 nm South of Block Island-
102 PM EDT Sat Oct 4 2025

.THIS AFTERNOON...SW winds 5 to 10 kt. Seas 3 to 4 ft. Wave
Detail: SE 3 ft at 11 seconds and SW 2 ft at 5 seconds.
.TONIGHT...W winds 5 to 10 kt. Seas 3 to 4 ft. Wave Detail: SE
3 ft at 12 seconds and SW 2 ft at 4 seconds.
.SUN...SW winds around 5 kt. Seas 2 to 3 ft. Wave Detail: SE 3 ft
at 12 seconds and SW 1 foot at 4 seconds. Patchy fog in the
afternoon with vsby 1 NM or less.
.SUN NIGHT...SW winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: SE
2 ft at 14 seconds and SW 1 foot at 4 seconds. Patchy fog. Vsby
1 NM or less, increasing to 1 to 3 NM after midnight.
.MON...SW winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: SW 2 ft
at 4 seconds and E 2 ft at 12 seconds. Patchy fog in the morning
with vsby 1 to 3 NM.
.MON NIGHT...SW winds 10 to 15 kt. Seas 2 to 3 ft. Wave Detail:
SW 2 ft at 4 seconds and E 2 ft at 11 seconds.
.TUE...SW winds 15 to 20 kt. Seas around 3 ft.
.TUE NIGHT...SW winds 15 to 20 kt with gusts up to 25 kt. Seas
3 to 5 ft. A chance of showers. Vsby 1 to 3 NM.
.WED...W winds 15 to 20 kt. Seas 3 to 5 ft. Showers. Vsby 1 to
3 NM.
.WED NIGHT...N winds 25 to 30 kt. Seas 4 to 6 ft. Showers likely.
Vsby 1 to 3 NM.

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.

$$

ANZ232-050600-
Nantucket Sound-
102 PM EDT Sat Oct 4 2025

.THIS AFTERNOON...SW winds 5 to 10 kt. Seas around 2 ft. Wave
Detail: SW 1 foot at 3 seconds and E 1 foot at 10 seconds.
.TONIGHT...SW winds 5 to 10 kt, becoming W after midnight. Seas
around 2 ft. Wave Detail: SW 1 foot at 3 seconds and E 1 foot at
11 seconds.
.SUN...SW winds around 5 kt, increasing to 5 to 10 kt in the
afternoon. Seas around 2 ft. Wave Detail: SW 1 foot at 4 seconds
and E 1 foot at 12 seconds.
.SUN NIGHT...SW winds 5 to 10 kt. Seas around 2 ft. Wave Detail:
SW 1 foot at 3 seconds and E 1 foot at 14 seconds.
.MON...SW winds 5 to 10 kt, increasing to 10 to 15 kt with gusts
up to 20 kt in the afternoon. Seas around 2 ft. Wave Detail: SW
2 ft at 3 seconds and E 1 foot at 12 seconds. Patchy fog in the
morning with vsby 1 to 3 NM.
.MON NIGHT...SW winds 10 to 15 kt. Seas around 2 ft. Wave Detail:
SW 2 ft at 3 seconds and E 1 foot at 11 seconds.
.TUE...SW winds 15 to 20 kt with gusts up to 25 kt. Seas 2 to
3 ft.
.TUE NIGHT...SW winds 15 to 20 kt with gusts up to 25 kt. Seas
around 3 ft. A chance of showers. Vsby 1 to 3 NM.
.WED AND WED NIGHT...W winds 15 to 20 kt, becoming N 20 to 25 kt
with gusts up to 30 kt. Seas 2 to 4 ft. Showers. Vsby 1 to 3 NM.

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.

$$

ANZ233-050600-
Vineyard Sound-
102 PM EDT Sat Oct 4 2025

.THIS AFTERNOON...SW winds 5 to 10 kt. Seas around 2 ft. Wave
Detail: SW 2 ft at 4 seconds and SE 1 foot at 10 seconds.
.TONIGHT...SW winds 5 to 10 kt, becoming W after midnight. Seas
around 2 ft. Wave Detail: SW 2 ft at 4 seconds and SE 1 foot at
10 seconds.
.SUN...NW winds around 5 kt, becoming SW in the afternoon. Seas
around 2 ft. Wave Detail: SW 1 foot at 4 seconds and SE 1 foot at
11 seconds.
.SUN NIGHT...SW winds 5 to 10 kt. Seas around 2 ft. Wave Detail:
SW 1 foot at 4 seconds and SE 1 foot at 12 seconds. Patchy fog
after midnight with vsby 1 to 3 NM.
.MON...SW winds 5 to 10 kt, increasing to 10 to 15 kt in the
afternoon. Seas around 2 ft. Wave Detail: SW 2 ft at 3 seconds
and SE 1 foot at 11 seconds. Patchy fog in the morning with vsby
1 to 3 NM.
.MON NIGHT...SW winds 10 to 15 kt. Seas around 2 ft. Wave Detail:
SW 2 ft at 4 seconds and SE 1 foot at 10 seconds.
.TUE...SW winds 15 to 20 kt with gusts up to 25 kt. Seas 2 to
4 ft.
.TUE NIGHT THROUGH WED NIGHT...N winds 15 to 20 kt with gusts up
to 25 kt. Seas 2 to 4 ft. Showers. Vsby 1 to 3 NM.

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.

$$

ANZ234-050600-
Buzzards Bay-
102 PM EDT Sat Oct 4 2025

.THIS AFTERNOON...SW winds 5 to 10 kt. Seas around 2 ft. Wave
Detail: SW 2 ft at 4 seconds and SE 1 foot at 10 seconds.
.TONIGHT...SW winds 5 to 10 kt, becoming W after midnight. Seas
around 2 ft in the evening, then 1 foot or less. Wave Detail: SW
1 foot at 4 seconds and SE 1 foot at 10 seconds, becoming SW
1 foot at 4 seconds and SE 1 foot at 11 seconds.
.SUN...Light and variable winds, becoming SW around 5 kt in the
afternoon. Seas 1 foot or less. Wave Detail: SW 1 foot at
4 seconds and SE 1 foot at 12 seconds.
.SUN NIGHT...SW winds 5 to 10 kt. Seas 1 foot or less. Wave
Detail: SW 1 foot at 4 seconds and SE 1 foot at 12 seconds.
Patchy fog. Vsby 1 to 3 NM.
.MON...SW 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 2 to 3 ft
in the afternoon. Wave Detail: SW 1 foot at 3 seconds and SE
1 foot at 11 seconds, becoming SW 2 ft at 3 seconds and SE 1 foot
at 10 seconds. Patchy fog in the morning with vsby 1 to 3 NM.
.MON NIGHT...SW winds 10 to 15 kt. Gusts up to 20 kt in the
evening. Seas around 2 ft. Wave Detail: SW 2 ft at 4 seconds and
SE 1 foot at 10 seconds.
.TUE...SW winds 15 to 20 kt with gusts up to 30 kt. Seas 2 to
4 ft.
.TUE NIGHT THROUGH WED NIGHT...N winds 15 to 20 kt with gusts up
to 25 kt. Seas 2 to 4 ft. Showers. Vsby 1 to 3 NM.

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.

$$

ANZ235-050600-
Rhode Island Sound-
102 PM EDT Sat Oct 4 2025

.THIS AFTERNOON...SW winds 5 to 10 kt. Seas 2 to 3 ft. Wave
Detail: SW 2 ft at 5 seconds and SE 2 ft at 11 seconds.
.TONIGHT...W winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: SW
2 ft at 4 seconds and SE 2 ft at 12 seconds.
.SUN...NW winds around 5 kt, becoming S in the afternoon. Seas
around 2 ft. Wave Detail: SE 2 ft at 12 seconds and SW 1 foot at
4 seconds.
.SUN NIGHT...SW winds 5 to 10 kt. Seas around 2 ft. Wave Detail:
SE 2 ft at 11 seconds and SW 1 foot at 4 seconds. Patchy fog.
Vsby 1 to 3 NM.
.MON...SW winds 5 to 10 kt, increasing to 10 to 15 kt with gusts
up to 20 kt in the afternoon. Seas around 2 ft. Wave Detail: SW
2 ft at 3 seconds and SE 1 foot at 10 seconds. Patchy fog in the
morning with vsby 1 to 3 NM.
.MON NIGHT...SW winds 10 to 15 kt. Seas 2 to 3 ft. Wave Detail:
SW 2 ft at 4 seconds and SE 1 foot at 10 seconds.
.TUE...SW winds 15 to 20 kt with gusts up to 25 kt. Seas 2 to
3 ft.
.TUE NIGHT THROUGH WED NIGHT...N winds 20 to 25 kt. Seas 2 to
4 ft. Showers. Vsby 1 to 3 NM.

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.

$$

ANZ237-050600-
Block Island Sound-
102 PM EDT Sat Oct 4 2025

.THIS AFTERNOON...SW winds 5 to 10 kt. Seas 2 to 3 ft. Wave
Detail: SW 2 ft at 4 seconds and SE 2 ft at 12 seconds.
.TONIGHT...W winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: W
2 ft at 3 seconds and SE 2 ft at 12 seconds.
.SUN...NE winds around 5 kt, becoming S in the afternoon. Seas
around 2 ft. Wave Detail: SE 2 ft at 12 seconds and SW 1 foot at
4 seconds.
.SUN NIGHT...SW winds 5 to 10 kt. Seas around 2 ft. Wave Detail:
SE 2 ft at 14 seconds and SW 1 foot at 4 seconds. Patchy fog.
Vsby 1 to 3 NM.
.MON...SW winds 5 to 10 kt. Seas around 2 ft. Wave Detail: SW
2 ft at 3 seconds and SE 2 ft at 12 seconds. Patchy fog in the
morning with vsby 1 to 3 NM.
.MON NIGHT...SW winds 10 to 15 kt. Seas around 2 ft. Wave Detail:
SW 2 ft at 3 seconds and SE 1 foot at 10 seconds.
.TUE...SW winds 15 to 20 kt with gusts up to 25 kt. Seas 2 to
3 ft.
.TUE NIGHT THROUGH WED NIGHT...N winds 15 to 20 kt with gusts up
to 25 kt. Seas 2 to 4 ft. Showers. Vsby 1 to 3 NM.

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.

$$

ANZ230-050600-
Boston Harbor-
102 PM EDT Sat Oct 4 2025

.THIS AFTERNOON...SE winds 5 to 10 kt. Waves 1 foot or less.
.TONIGHT...SW winds 5 to 10 kt, becoming NW after midnight. Waves
1 foot or less.
.SUN...N winds around 5 kt, becoming E around 5 kt in the
afternoon. Waves 1 foot or less.
.SUN NIGHT...S winds around 5 kt. Waves 1 foot or less.
.MON AND MON NIGHT...SW winds 10 to 15 kt. Waves around 2 ft.
.TUE...SW winds 15 to 20 kt with gusts up to 25 kt. Waves around
2 ft.
.TUE NIGHT AND WED...SW winds 15 to 20 kt, becoming W 10 to
15 kt. Gusts up to 25 kt. Waves around 2 ft. Showers likely. Vsby
1 to 3 NM.
.WED NIGHT...N winds 10 to 15 kt with gusts up to 20 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.

$$

ANZ236-050600-
Narragansett Bay-
102 PM EDT Sat Oct 4 2025

.THIS AFTERNOON...S winds 5 to 10 kt. Waves around 2 ft.
.TONIGHT...SW winds 5 to 10 kt, becoming NW after midnight. Waves
around 2 ft.
.SUN...NE winds around 5 kt, becoming S around 5 kt in the
afternoon. Waves around 2 ft.
.SUN NIGHT...SW winds around 5 kt. Waves around 2 ft in the
evening, then 1 foot or less. Patchy fog. Vsby 1 to 3 NM.
.MON...SW winds 5 to 10 kt, increasing to 10 to 15 kt with gusts
up to 20 kt in the afternoon. Waves 1 foot or less, then around
2 ft in the afternoon. Patchy fog in the morning with vsby 1 to
3 NM.
.MON NIGHT...SW winds 10 to 15 kt. Waves around 2 ft.
.TUE...SW winds 15 to 20 kt with gusts up to 25 kt. Waves 2 to
3 ft.
.TUE NIGHT AND WED...SW winds 15 to 20 kt, becoming W 10 to
15 kt. Gusts up to 25 kt. Waves 2 to 3 ft. Showers. Vsby 1 to
3 NM.
.WED NIGHT...N winds 10 to 15 kt with gusts up to 20 kt. Waves
around 2 ft. A chance of showers. Vsby 1 to 3 NM.

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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