809
FZUS51 KBOX 122006
CWFBOX

Coastal Waters Forecast for Massachusetts and Rhode Island
National Weather Service Boston/Norton MA
406 PM EDT Sat Jul 12 2025

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

ANZ200-130900-
406 PM EDT Sat Jul 12 2025

.Synopsis for Massachusetts and Rhode Island coastal waters...
High pres dominates this weekend. Cold front moves through Mon
bringing a period of unsettled weather through the week.

$$

ANZ250-130900-
Coastal waters east of Ipswich Bay and the Stellwagen Bank
National Marine Sanctuary-
406 PM EDT Sat Jul 12 2025

.TONIGHT...SE 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: SE 2 ft at 5 seconds and SE 2 ft at 10 seconds. Patchy
fog. Vsby 1 NM or less.
.SUN...SE 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: SE
2 ft at 8 seconds and SE 1 foot at 5 seconds. Patchy fog in the
morning with vsby 1 NM or less.
.SUN NIGHT...SE winds 10 to 15 kt with gusts up to 20 kt,
diminishing to 5 to 10 kt after midnight. Seas 2 to 3 ft. Wave
Detail: SE 2 ft at 5 seconds and SE 2 ft at 8 seconds.
.MON...S winds 5 to 10 kt, increasing to 10 to 15 kt in the
afternoon. Seas 2 to 3 ft. Wave Detail: SE 2 ft at 6 seconds.
.MON NIGHT AND TUE...S winds 10 to 15 kt with gusts up to 20 kt.
Seas 2 to 3 ft. Wave Detail: SE 2 ft at 7 seconds and SW 1 foot
at 3 seconds.
.TUE NIGHT...SW winds around 10 kt. Seas around 2 ft. Wave
Detail: E 2 ft at 7 seconds and S 1 foot at 3 seconds.
.WED THROUGH THU NIGHT...SW winds 15 to 20 kt with gusts up to
25 kt. Seas 2 to 4 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.

$$

ANZ251-130900-
Massachusetts Bay and Ipswich Bay-
406 PM EDT Sat Jul 12 2025

.TONIGHT...SE 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: SE 2 ft at 4 seconds and SE 1 foot at 10 seconds. Patchy
fog. Vsby 1 NM or less.
.SUN...SE 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: SE
2 ft at 5 seconds and SE 1 foot at 10 seconds. Patchy fog in the
morning with vsby 1 NM or less.
.SUN NIGHT...SE winds 10 to 15 kt with gusts up to 20 kt,
becoming S 5 to 10 kt after midnight. Seas 2 to 3 ft. Wave
Detail: SE 2 ft at 5 seconds and SE 1 foot at 9 seconds.
.MON...S winds 5 to 10 kt, becoming SE 10 to 15 kt in the
afternoon. Seas around 2 ft. Wave Detail: SE 2 ft at 4 seconds
and E 2 ft at 8 seconds.
.MON NIGHT...S winds 10 to 15 kt, becoming SW 5 to 10 kt after
midnight. Seas around 2 ft. Wave Detail: SE 2 ft at 4 seconds and
E 2 ft at 8 seconds.
.TUE AND TUE NIGHT...SW winds 5 to 10 kt. Seas around 2 ft. Wave
Detail: E 2 ft at 7 seconds and SW 1 foot at 2 seconds.
.WED THROUGH THU NIGHT...SW 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.

$$

ANZ231-130900-
Cape Cod Bay-
406 PM EDT Sat Jul 12 2025

.TONIGHT...SE winds 5 to 10 kt. Seas 1 foot or less. Wave Detail:
SE 1 foot at 4 seconds and SE 1 foot at 9 seconds. Patchy fog.
Vsby 1 NM or less.
.SUN...SE winds 5 to 10 kt. Seas 1 foot or less, then around 2 ft
in the afternoon. Wave Detail: SE 1 foot at 3 seconds and SE
1 foot at 9 seconds. Patchy fog in the morning with vsby 1 NM or
less.
.SUN NIGHT...SE winds 5 to 10 kt. Seas 1 foot or less. Wave
Detail: SE 1 foot at 4 seconds and SE 1 foot at 9 seconds. Patchy
fog after midnight.
.MON...S winds 5 to 10 kt. Seas 1 foot or less, then around 2 ft
in the afternoon. Wave Detail: SE 1 foot at 5 seconds and SE
1 foot at 8 seconds, becoming SW 1 foot at 2 seconds and S 1 foot
at 2 seconds.
.MON NIGHT THROUGH TUE NIGHT...SW winds 5 to 10 kt. Seas around
2 ft. Wave Detail: SW 1 foot at 2 seconds and S 1 foot at
4 seconds.
.WED AND WED 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 SE
1 foot at 7 seconds.
.THU AND THU NIGHT...SW winds 10 to 15 kt with gusts up to 25 kt.
Seas 2 to 4 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.

$$

ANZ254-130900-
Coastal waters from Provincetown MA to Chatham MA to Nantucket MA
out 20 nm-
406 PM EDT Sat Jul 12 2025

.TONIGHT...SE winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: S
3 ft at 7 seconds and SE 2 ft at 10 seconds. Patchy fog. Vsby
1 NM or less.
.SUN...E winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: S 3 ft at
7 seconds and SE 2 ft at 10 seconds. Patchy fog in the morning
with vsby 1 NM or less.
.SUN NIGHT...SE winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: SE
2 ft at 7 seconds and SE 2 ft at 10 seconds. Patchy fog after
midnight.
.MON...SE winds 5 to 10 kt, becoming S in the afternoon. Seas
2 to 3 ft. Wave Detail: SE 2 ft at 7 seconds.
.MON NIGHT THROUGH TUE NIGHT...SW winds 5 to 10 kt. Seas 2 to
3 ft. Wave Detail: SW 2 ft at 3 seconds and SE 2 ft at 7 seconds.
.WED THROUGH THU NIGHT...SW winds 15 to 20 kt with gusts up to
25 kt. Seas 2 to 4 ft. Wave Detail: S 4 ft at 8 seconds and W
2 ft at 4 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.

$$

ANZ255-130900-
Coastal Waters extending out to 25 nm South of Marthas Vineyard
and Nantucket-
406 PM EDT Sat Jul 12 2025

.TONIGHT...E winds around 10 kt. Seas around 3 ft. Wave Detail:
SE 3 ft at 9 seconds and E 1 foot at 4 seconds. Patchy fog. Vsby
1 NM or less.
.SUN...E winds around 10 kt. Seas 2 to 3 ft. Wave Detail: S 3 ft
at 7 seconds and SE 2 ft at 10 seconds. Patchy fog in the morning
with vsby 1 NM or less.
.SUN NIGHT...E winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: SE
2 ft at 6 seconds and SE 2 ft at 10 seconds. Patchy fog. Vsby
1 to 3 NM.
.MON...E winds 5 to 10 kt, becoming S in the afternoon. Seas 2 to
3 ft. Wave Detail: SE 2 ft at 6 seconds and SE 2 ft at 9 seconds.
.MON NIGHT THROUGH TUE NIGHT...SW winds 5 to 10 kt. Seas 2 to
3 ft. Wave Detail: SW 2 ft at 3 seconds and SE 2 ft at 7 seconds.
.WED AND WED NIGHT...SW winds 10 to 15 kt with gusts up to 20 kt.
Seas 2 to 4 ft. Wave Detail: SW 4 ft at 5 seconds and E 1 foot at
6 seconds.
.THU...SW winds 15 to 20 kt with gusts up to 25 kt. Seas 3 to
5 ft.
.THU NIGHT...SW winds 15 to 20 kt with gusts up to 25 kt. Seas
4 to 5 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.

$$

ANZ256-130900-
Coastal Waters from Montauk NY to Marthas Vineyard extending out
to 20 nm South of Block Island-
406 PM EDT Sat Jul 12 2025

.TONIGHT...E winds around 10 kt. Seas 3 to 4 ft. Wave Detail: SE
3 ft at 8 seconds. Patchy fog. Vsby 1 NM or less.
.SUN...E winds around 10 kt. Seas around 3 ft. Wave Detail: S
3 ft at 7 seconds and SE 3 ft at 10 seconds. Patchy fog in the
morning with vsby 1 NM or less.
.SUN NIGHT...E winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: SE
3 ft at 7 seconds and E 1 foot at 4 seconds. Patchy fog. Vsby
1 to 3 NM.
.MON...SE winds 5 to 10 kt, becoming S in the afternoon. Seas
2 to 3 ft. Wave Detail: SE 2 ft at 6 seconds and SE 2 ft at
9 seconds. Patchy fog in the morning.
.MON NIGHT THROUGH TUE NIGHT...SW winds 10 to 15 kt. Seas 2 to
3 ft. Wave Detail: SW 2 ft at 3 seconds and SE 2 ft at 6 seconds.
.WED AND WED NIGHT...SW winds 10 to 15 kt with gusts up to 20 kt.
Seas 2 to 4 ft. Wave Detail: SW 4 ft at 6 seconds and E 1 foot at
6 seconds.
.THU...SW winds 15 to 20 kt with gusts up to 25 kt. Seas 3 to
5 ft.
.THU NIGHT...SW winds 15 to 20 kt with gusts up to 25 kt. Seas
4 to 5 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.

$$

ANZ232-130900-
Nantucket Sound-
406 PM EDT Sat Jul 12 2025

.TONIGHT...E winds 5 to 10 kt. Seas around 2 ft. Wave Detail: S
2 ft at 8 seconds and E 1 foot at 3 seconds. Patchy fog. Vsby
1 NM or less.
.SUN...E winds 5 to 10 kt. Seas around 2 ft. Wave Detail: E
1 foot at 3 seconds and S 1 foot at 7 seconds. Patchy fog in the
morning with vsby 1 NM or less.
.SUN NIGHT...SE winds 5 to 10 kt. Seas around 2 ft. Wave Detail:
E 1 foot at 4 seconds and S 1 foot at 7 seconds. Patchy fog.
.MON...SE winds 5 to 10 kt, becoming S in the afternoon. Seas
around 2 ft. Wave Detail: SW 1 foot at 2 seconds and SE 1 foot at
7 seconds.
.MON NIGHT THROUGH TUE NIGHT...SW winds 10 to 15 kt. Seas around
2 ft. Wave Detail: SW 1 foot at 3 seconds and SE 1 foot at
7 seconds.
.WED THROUGH 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
3 ft at 7 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.

$$

ANZ233-130900-
Vineyard Sound-
406 PM EDT Sat Jul 12 2025

.TONIGHT...E winds 5 to 10 kt. Seas around 2 ft. Wave Detail: SE
2 ft at 8 seconds and E 1 foot at 3 seconds. Patchy fog. Vsby
1 NM or less.
.SUN...E winds 5 to 10 kt. Seas around 2 ft. Wave Detail: S 2 ft
at 7 seconds and E 1 foot at 3 seconds. Patchy fog in the morning
with vsby 1 NM or less.
.SUN NIGHT...SE winds 5 to 10 kt. Seas around 2 ft. Wave Detail:
E 1 foot at 3 seconds and S 1 foot at 7 seconds. Patchy fog after
midnight.
.MON...SE winds 5 to 10 kt, becoming S in the afternoon. Seas
around 2 ft. Wave Detail: SW 1 foot at 2 seconds and SE 1 foot at
7 seconds. Patchy fog in the morning.
.MON NIGHT THROUGH TUE NIGHT...SW winds 10 to 15 kt. Seas around
2 ft. Wave Detail: SW 1 foot at 3 seconds and SE 1 foot at
7 seconds.
.WED THROUGH THU NIGHT...SW winds 15 to 20 kt with gusts up to
25 kt. Seas 2 to 4 ft. Wave Detail: S 4 ft at 7 seconds and SW
2 ft at 4 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.

$$

ANZ234-130900-
Buzzards Bay-
406 PM EDT Sat Jul 12 2025

.TONIGHT...SE winds 5 to 10 kt. Seas around 2 ft. Wave Detail: S
2 ft at 8 seconds and E 1 foot at 3 seconds. Patchy fog. Vsby
1 NM or less.
.SUN...E winds 5 to 10 kt. Seas around 2 ft. Wave Detail: S 2 ft
at 7 seconds and E 1 foot at 2 seconds. Patchy fog in the morning
with vsby 1 NM or less.
.SUN NIGHT...SE winds 5 to 10 kt. Seas around 2 ft. Wave Detail:
E 1 foot at 3 seconds and S 1 foot at 6 seconds. Patchy fog after
midnight.
.MON...SE winds 5 to 10 kt, becoming S in the afternoon. Seas
1 foot or less, then around 2 ft in the afternoon. Wave Detail:
SE 1 foot at 7 seconds, becoming SW 1 foot at 3 seconds and SE
1 foot at 7 seconds. Patchy fog in the morning.
.MON NIGHT THROUGH TUE NIGHT...SW winds 10 to 15 kt. Seas around
2 ft. Wave Detail: SW 1 foot at 3 seconds and SE 1 foot at
6 seconds.
.WED THROUGH THU NIGHT...SW winds 15 to 20 kt with gusts up to
25 kt. Seas 2 to 4 ft. Wave Detail: S 3 ft at 7 seconds and SW
2 ft at 3 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.

$$

ANZ235-130900-
Rhode Island Sound-
406 PM EDT Sat Jul 12 2025

.TONIGHT...E winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: SE
3 ft at 9 seconds and E 1 foot at 3 seconds. Patchy fog. Vsby
1 NM or less.
.SUN...E winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: SE 3 ft
at 9 seconds. Patchy fog in the morning with vsby 1 NM or less.
.SUN NIGHT...SE winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: S
2 ft at 7 seconds and E 1 foot at 4 seconds. Patchy fog. Vsby
1 to 3 NM after midnight.
.MON...SE winds 5 to 10 kt, becoming S in the afternoon. Seas
around 2 ft. Wave Detail: SE 2 ft at 7 seconds. Patchy fog in the
morning.
.MON NIGHT THROUGH TUE NIGHT...SW winds 10 to 15 kt. Seas around
2 ft. Wave Detail: SW 2 ft at 3 seconds and SE 2 ft at 7 seconds.
.WED THROUGH THU...SW winds 15 to 20 kt with gusts up to 25 kt.
Seas 2 to 4 ft. Wave Detail: SE 4 ft at 8 seconds and SW 2 ft at
5 seconds.
.THU NIGHT...SW winds 15 to 20 kt with gusts up to 25 kt. Seas
3 to 4 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.

$$

ANZ237-130900-
Block Island Sound-
406 PM EDT Sat Jul 12 2025

.TONIGHT...E winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: S
3 ft at 8 seconds. Patchy fog. Vsby 1 NM or less.
.SUN...E winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: SE 3 ft
at 8 seconds. Patchy fog in the morning with vsby 1 NM or less.
.SUN NIGHT...E winds 5 to 10 kt. Seas around 2 ft. Wave Detail:
SE 2 ft at 8 seconds and E 1 foot at 4 seconds. Patchy fog.
.MON...SE winds 5 to 10 kt, becoming S in the afternoon. Seas
around 2 ft. Wave Detail: SE 2 ft at 7 seconds. Patchy fog in the
morning.
.MON NIGHT THROUGH TUE NIGHT...SW winds 5 to 10 kt. Seas around
2 ft. Wave Detail: SE 2 ft at 6 seconds and SW 1 foot at
2 seconds.
.WED THROUGH THU...SW winds 10 to 15 kt with gusts up to 25 kt.
Seas 2 to 4 ft. Wave Detail: SE 4 ft at 8 seconds and W 1 foot at
3 seconds.
.THU NIGHT...SW winds 10 to 15 kt with gusts up to 25 kt. Seas
2 to 4 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.

$$

ANZ230-130900-
Boston Harbor-
406 PM EDT Sat Jul 12 2025

.TONIGHT...SE winds 10 to 15 kt with gusts up to 20 kt,
diminishing to 5 to 10 kt after midnight. Waves around 2 ft this
evening, then 1 foot or less. Patchy fog. Vsby 1 to 3 NM,
decreasing to 1 NM or less after midnight.
.SUN...SE 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 NM
or less.
.SUN NIGHT...SE winds 10 to 15 kt with gusts up to 20 kt,
becoming S 5 to 10 kt after midnight. Waves around 2 ft in the
evening, then 1 foot or less.
.MON...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.
.MON NIGHT AND TUE...S winds 5 to 10 kt. Waves 1 foot or less.
.TUE NIGHT...SW winds 5 to 10 kt. Waves 1 foot or less.
.WED AND WED NIGHT...SW winds 10 to 15 kt. Waves around 2 ft.
.THU AND THU NIGHT...SW 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.

$$

ANZ236-130900-
Narragansett Bay-
406 PM EDT Sat Jul 12 2025

.TONIGHT...SE winds 5 to 10 kt. Waves around 2 ft. Patchy fog.
Vsby 1 NM or less.
.SUN...SE winds 5 to 10 kt. Waves around 2 ft. Patchy fog in the
morning with vsby 1 NM or less.
.SUN NIGHT...SE winds 5 to 10 kt. Waves around 2 ft. Patchy fog
after midnight with vsby 1 to 3 NM.
.MON...S winds 5 to 10 kt. Waves around 2 ft. Patchy fog in the
morning.
.MON NIGHT THROUGH TUE NIGHT...SW winds 5 to 10 kt. Waves around
2 ft.
.WED THROUGH THU NIGHT...SW winds 10 to 15 kt with gusts up to
20 kt. Waves 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.

$$

For the latest updates...please visit our webpage at
www.weather.gov/boston

You can follow us on Facebook at
www.facebook.com/NWSBoston

You can follow us on Twitter at
@NWSBoston