644
FZUS51 KBOX 040803
CWFBOX

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

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

ANZ200-042100-
403 AM 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.

$$

ANZ250-042100-
Coastal waters east of Ipswich Bay and the Stellwagen Bank
National Marine Sanctuary-
403 AM EDT Sat Oct 4 2025

.TODAY...W winds 5 to 10 kt, becoming SW this afternoon. Seas
2 to 4 ft. Wave Detail: E 3 ft at 10 seconds and W 2 ft at
4 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.
.SUN NIGHT...SW 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.

$$

ANZ251-042100-
Massachusetts Bay and Ipswich Bay-
403 AM EDT Sat Oct 4 2025

.TODAY...W winds 5 to 10 kt, becoming SE this afternoon. Seas
2 to 3 ft. Wave Detail: E 3 ft at 10 seconds and W 2 ft 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.

$$

ANZ231-042100-
Cape Cod Bay-
403 AM EDT Sat Oct 4 2025

.TODAY...W winds 5 to 10 kt, becoming SE this afternoon. 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 W after midnight. 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...SW 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.

$$

ANZ254-042100-
Coastal waters from Provincetown MA to Chatham MA to Nantucket MA
out 20 nm-
403 AM EDT Sat Oct 4 2025

.TODAY...W winds 5 to 10 kt. Seas 2 to 4 ft. Wave Detail: W 3 ft
at 4 seconds and E 3 ft at 10 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.
.MON AND 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 3 seconds and E 2 ft at
11 seconds.
.TUE...SW winds 10 to 15 kt with gusts up to 25 kt. Seas 2 to
3 ft. Wave Detail: SW 3 ft at 4 seconds and E 2 ft at 10 seconds.
.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.

$$

ANZ255-042100-
Coastal Waters extending out to 25 nm South of Marthas Vineyard
and Nantucket-
403 AM EDT Sat Oct 4 2025

.TODAY...W winds 10 to 15 kt. Seas 3 to 5 ft. Wave Detail: W 3 ft
at 5 seconds and E 3 ft at 10 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 in the
afternoon with vsby 1 to 3 NM.
.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 in the
evening with vsby 1 to 3 NM.
.MON AND MON NIGHT...SW winds 10 to 15 kt. Seas 2 to 3 ft. Wave
Detail: SW 2 ft at 3 seconds and E 2 ft at 11 seconds.
.TUE...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 10 seconds.
.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.

$$

ANZ256-042100-
Coastal Waters from Montauk NY to Marthas Vineyard extending out
to 20 nm South of Block Island-
403 AM EDT Sat Oct 4 2025

.TODAY...W winds 10 to 15 kt. Seas 3 to 5 ft. Wave Detail: W 3 ft
at 5 seconds and SE 3 ft at 11 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.
.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.
.MON AND 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 12 seconds.
.TUE...SW winds 15 to 20 kt. Seas around 3 ft. Wave Detail: SW
3 ft at 4 seconds and SE 2 ft at 10 seconds.
.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.

$$

ANZ232-042100-
Nantucket Sound-
403 AM EDT Sat Oct 4 2025

.TODAY...W winds 10 to 15 kt, becoming SW 5 to 10 kt this
afternoon. Seas 2 to 3 ft. Wave Detail: W 2 ft at 4 seconds and E
2 ft 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 5 to 10 kt. 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 AND MON NIGHT...SW 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 12 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 4 seconds and E 1 foot at
10 seconds.
.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.

$$

ANZ233-042100-
Vineyard Sound-
403 AM EDT Sat Oct 4 2025

.TODAY...W winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: SW 2 ft
at 5 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.
.MON AND 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 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 SE 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.

$$

ANZ234-042100-
Buzzards Bay-
403 AM EDT Sat Oct 4 2025

.TODAY...SW winds 5 to 10 kt. Seas around 2 ft. Wave Detail: SW
2 ft at 5 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...N winds around 5 kt, becoming S 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.
.MON AND 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 3 seconds and SE 1 foot
at 11 seconds.
.TUE...SW winds 15 to 20 kt with gusts up to 30 kt. Seas 2 to
4 ft. Wave Detail: SW 3 ft at 4 seconds and SE 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.

$$

ANZ235-042100-
Rhode Island Sound-
403 AM EDT Sat Oct 4 2025

.TODAY...SW winds 10 to 15 kt. Seas 2 to 3 ft. Wave Detail: SW
3 ft at 4 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...N 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.
.MON AND 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 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. Wave Detail: SW 3 ft at 4 seconds and SE 1 foot at
10 seconds.
.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.

$$

ANZ237-042100-
Block Island Sound-
403 AM EDT Sat Oct 4 2025

.TODAY...W winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: W 2 ft
at 4 seconds and SE 2 ft at 11 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.
.MON AND MON NIGHT...SW winds 10 to 15 kt. Seas around 2 ft. Wave
Detail: SW 2 ft at 3 seconds and SE 2 ft at 12 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 4 seconds and SE 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.

$$

ANZ230-042100-
Boston Harbor-
403 AM EDT Sat Oct 4 2025

.TODAY...W winds 5 to 10 kt, becoming SE this afternoon. 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 in the afternoon. Waves
1 foot or less.
.SUN NIGHT...S winds 5 to 10 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.

$$

ANZ236-042100-
Narragansett Bay-
403 AM EDT Sat Oct 4 2025

.TODAY...W winds 5 to 10 kt, becoming S this afternoon. Waves
around 2 ft.
.TONIGHT...SW winds 5 to 10 kt, becoming NW after midnight. Waves
around 2 ft.
.SUN...N winds around 5 kt, becoming S in the afternoon. Waves
around 2 ft.
.SUN NIGHT...SW winds 5 to 10 kt. Waves around 2 ft in the
evening, then 1 foot or less.
.MON AND MON NIGHT...SW winds 10 to 15 kt with gusts up to 20 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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