HomeForecastsMassachusetts ForecastsCohasset Harbor, MA - (White Head) Coastal Forecast

Cohasset Harbor, MA - (White Head) Coastal Forecast

FZUS51 KBOX 111105
CWFBOX

Coastal Waters Forecast for Massachusetts and Rhode Island
National Weather Service Boston/Norton MA
704 AM EDT Tue Mar 11 2025

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

ANZ200-120000-
704 AM EDT Tue Mar 11 2025

.Synopsis for Massachusetts and Rhode Island coastal waters...
A cold front will drop S into northern New Eng late today and this
evening and cross the waters late tonight. High pres builds across
srn Quebec Wed, then a weak low pres along a warm front will
track S of the waters late Wed night into Thu. Weak high pres builds
over the waters Fri, then increasing S flow develops Sat ahead of
strong low pres moving into the Great Lakes.

$$

ANZ250-120000-
Coastal waters east of Ipswich Bay and the Stellwagen Bank
National Marine Sanctuary-
704 AM EDT Tue Mar 11 2025

...SMALL CRAFT ADVISORY IN EFFECT THROUGH WEDNESDAY MORNING...

.TODAY...S winds 10 to 15 kt, increasing to 15 to 20 kt this
afternoon. Gusts up to 30 kt. Seas 2 to 4 ft. Wave Detail: S 3 ft
at 4 seconds and NW 1 foot at 3 seconds.
.TONIGHT...S winds 15 to 20 kt, becoming W after midnight. Gusts
up to 30 kt. Seas 2 to 4 ft. Wave Detail: SE 3 ft at 4 seconds
and W 2 ft at 3 seconds.
.WED...N winds 15 to 20 kt, diminishing to 10 to 15 kt in the
afternoon. Gusts up to 30 kt. Seas 2 to 4 ft. Wave Detail: N 3 ft
at 5 seconds and SE 2 ft at 9 seconds.
.WED NIGHT...E winds 5 to 10 kt. Seas 2 to 4 ft. Wave Detail: SE
4 ft at 9 seconds and N 3 ft at 5 seconds.
.THU AND THU NIGHT...E winds 10 to 15 kt. Seas 3 to 5 ft. Wave
Detail: SE 4 ft at 9 seconds and NE 2 ft at 5 seconds.
.FRI THROUGH SAT NIGHT...S winds 15 to 20 kt with gusts up to
25 kt. Seas 3 to 5 ft. Wave Detail: S 4 ft at 5 seconds and E
4 ft at 10 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.

$$

ANZ251-120000-
Massachusetts Bay and Ipswich Bay-
704 AM EDT Tue Mar 11 2025

...SMALL CRAFT ADVISORY IN EFFECT FROM 11 AM EDT THIS MORNING
THROUGH THIS EVENING...

.TODAY...S winds 10 to 15 kt, increasing to 15 to 20 kt this
afternoon. Gusts up to 25 kt. Seas 2 to 3 ft. Wave Detail: S 3 ft
at 4 seconds and E 1 foot at 9 seconds.
.TONIGHT...S winds 15 to 20 kt, becoming W after midnight. Gusts
up to 25 kt. Seas 2 to 3 ft. Wave Detail: SE 3 ft at 4 seconds
and W 2 ft at 3 seconds.
.WED...N winds 15 to 20 kt, becoming NE 10 to 15 kt in the
afternoon. Gusts up to 25 kt. Seas 2 to 3 ft. Wave Detail: N 2 ft
at 4 seconds and SE 1 foot at 5 seconds.
.WED NIGHT...E winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: N
2 ft at 4 seconds and SE 2 ft at 9 seconds.
.THU...SE winds 10 to 15 kt. Seas 2 to 3 ft. Wave Detail: E 3 ft
at 10 seconds and E 2 ft at 5 seconds.
.THU NIGHT...E winds 5 to 10 kt. Seas 3 to 4 ft. Wave Detail: E
4 ft at 9 seconds and E 1 foot at 4 seconds.
.FRI THROUGH SAT...SE winds 10 to 15 kt. Seas 2 to 4 ft.
.SAT NIGHT...S winds 15 to 20 kt with gusts up to 25 kt. Seas
3 to 4 ft. A chance of rain.

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.

$$

ANZ231-120000-
Cape Cod Bay-
704 AM EDT Tue Mar 11 2025

.TODAY...S winds 5 to 10 kt, increasing to 10 to 15 kt this
afternoon. Gusts up to 20 kt. Seas 1 foot or less, then around
2 ft this afternoon. Wave Detail: S 1 foot at 2 seconds and NW
1 foot at 3 seconds, becoming S 1 foot at 3 seconds and SE 1 foot
at 9 seconds.
.TONIGHT...S winds 10 to 15 kt, becoming W after midnight. Gusts
up to 25 kt. Seas around 2 ft. Wave Detail: W 1 foot at 3 seconds
and SE 1 foot at 4 seconds.
.WED...N winds 15 to 20 kt, diminishing to 10 to 15 kt in the
afternoon. Gusts up to 25 kt. Seas 2 to 3 ft. Wave Detail: N 3 ft
at 4 seconds and SE 2 ft at 9 seconds.
.WED NIGHT...E winds 5 to 10 kt. Seas around 2 ft. Wave Detail: N
2 ft at 4 seconds and SE 2 ft at 9 seconds.
.THU...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. A chance of rain in the
afternoon.
.THU NIGHT...E winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: E
3 ft at 9 seconds and SE 1 foot at 3 seconds.
.FRI THROUGH SAT NIGHT...S 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.

$$

ANZ254-120000-
Coastal waters from Provincetown MA to Chatham MA to Nantucket MA
out 20 nm-
704 AM EDT Tue Mar 11 2025

.TODAY...S winds 5 to 10 kt, increasing to 10 to 15 kt this
afternoon. Gusts up to 20 kt. Seas 2 to 3 ft. Wave Detail: SE
2 ft at 7 seconds and NW 1 foot at 4 seconds.
.TONIGHT...S winds 10 to 15 kt, becoming W after midnight. Gusts
up to 25 kt. Seas 2 to 3 ft. Wave Detail: SE 2 ft at 4 seconds
and SE 1 foot at 9 seconds.
.WED...N winds 15 to 20 kt with gusts up to 25 kt. Seas 3 to
5 ft. Wave Detail: N 4 ft at 5 seconds and SE 4 ft at 9 seconds.
.WED NIGHT...NE winds 5 to 10 kt. Seas 4 to 5 ft. Wave Detail: SE
4 ft at 9 seconds and N 3 ft at 6 seconds.
.THU AND THU NIGHT...E winds 10 to 15 kt. Seas 4 to 5 ft. Wave
Detail: SE 5 ft at 9 seconds and N 2 ft at 5 seconds.
.FRI THROUGH SAT NIGHT...S winds 15 to 20 kt with gusts up to
25 kt. Seas 3 to 5 ft. Wave Detail: E 5 ft at 10 seconds and S
4 ft at 5 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.

$$

ANZ255-120000-
Coastal Waters extending out to 25 nm South of Marthas Vineyard
and Nantucket-
704 AM EDT Tue Mar 11 2025

.TODAY...S winds 5 to 10 kt. Seas around 2 ft. Wave Detail: SW
2 ft at 6 seconds and SE 1 foot at 9 seconds.
.TONIGHT...S winds 5 to 10 kt, becoming W 10 to 15 kt with gusts
up to 20 kt after midnight. Seas 2 to 3 ft. Wave Detail: S 3 ft
at 9 seconds and W 1 foot at 3 seconds.
.WED...N winds 15 to 20 kt with gusts up to 25 kt. Seas 3 to
5 ft. Wave Detail: S 5 ft at 9 seconds and N 3 ft at 4 seconds.
.WED NIGHT...E winds around 10 kt. Seas 3 to 5 ft. Wave Detail:
SE 5 ft at 9 seconds and N 2 ft at 4 seconds.
.THU AND THU NIGHT...NE winds 10 to 15 kt. Seas 3 to 5 ft. Wave
Detail: SE 4 ft at 9 seconds and E 2 ft at 5 seconds.
.FRI...NE winds 5 to 10 kt. Seas 3 to 5 ft. Wave Detail: E 4 ft
at 9 seconds and NE 1 foot at 4 seconds.
.FRI NIGHT AND SAT...E winds 5 to 10 kt, becoming SE 10 to 15 kt.
Seas 2 to 4 ft.
.SAT NIGHT...S winds 15 to 20 kt with gusts up to 25 kt. Seas
4 to 6 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.

$$

ANZ256-120000-
Coastal Waters from Montauk NY to Marthas Vineyard extending out
to 20 nm South of Block Island-
704 AM EDT Tue Mar 11 2025

.TODAY...S winds 5 to 10 kt. Seas around 2 ft. Wave Detail: S
2 ft at 5 seconds and SE 1 foot at 8 seconds.
.TONIGHT...S winds around 10 kt, becoming W with gusts up to
20 kt after midnight. Seas 2 to 4 ft. Wave Detail: S 3 ft at
9 seconds and SW 2 ft at 4 seconds.
.WED...N winds 15 to 20 kt, becoming NE 10 to 15 kt in the
afternoon. Gusts up to 25 kt. Seas 3 to 5 ft. Wave Detail: S 5 ft
at 9 seconds and N 3 ft at 4 seconds.
.WED NIGHT...E winds 10 to 15 kt. Seas 4 to 5 ft. Wave Detail: SE
5 ft at 9 seconds and NE 2 ft at 4 seconds.
.THU AND THU NIGHT...NE winds 10 to 15 kt. Seas 4 to 5 ft. Wave
Detail: SE 5 ft at 9 seconds and E 1 foot at 3 seconds.
.FRI THROUGH SAT...SE winds 10 to 15 kt with gusts up to 20 kt.
Seas 3 to 5 ft. Wave Detail: E 4 ft at 9 seconds and S 3 ft at
6 seconds.
.SAT NIGHT...S winds 20 to 25 kt. Seas 4 to 6 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.

$$

ANZ232-120000-
Nantucket Sound-
704 AM EDT Tue Mar 11 2025

.TODAY...S winds 5 to 10 kt. Seas around 2 ft. Wave Detail: NW
1 foot at 3 seconds and S 1 foot at 5 seconds.
.TONIGHT...S winds around 10 kt, becoming W with gusts up to
20 kt after midnight. Seas around 2 ft. Wave Detail: SE 1 foot at
3 seconds and SE 1 foot at 9 seconds.
.WED...N winds 15 to 20 kt, becoming NE 10 to 15 kt in the
afternoon. Gusts up to 25 kt. Seas 2 to 3 ft. Wave Detail: N 2 ft
at 4 seconds and S 2 ft at 9 seconds.
.WED NIGHT...E winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: N
2 ft at 4 seconds and SE 2 ft at 9 seconds.
.THU...E winds 10 to 15 kt. Seas 2 to 3 ft. Wave Detail: SE 2 ft
at 5 seconds and SE 2 ft at 9 seconds. A chance of rain in the
afternoon.
.THU NIGHT...E winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: SE
2 ft at 9 seconds and E 1 foot at 4 seconds.
.FRI THROUGH SAT NIGHT...S 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.

$$

ANZ233-120000-
Vineyard Sound-
704 AM EDT Tue Mar 11 2025

.TODAY...S winds 5 to 10 kt. Seas around 2 ft this morning, then
1 foot or less. Wave Detail: S 2 ft at 6 seconds, becoming S
1 foot at 4 seconds and SE 1 foot at 9 seconds.
.TONIGHT...S winds around 10 kt, becoming W with gusts up to
20 kt after midnight. Seas 1 foot or less, then around 2 ft after
midnight. Wave Detail: S 1 foot at 4 seconds and SE 1 foot at
8 seconds, becoming SW 1 foot at 4 seconds and S 1 foot at
9 seconds.
.WED...N winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to
3 ft. Wave Detail: S 3 ft at 9 seconds and N 2 ft at 3 seconds.
.WED NIGHT...E winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: S
2 ft at 10 seconds and N 1 foot at 4 seconds.
.THU...E winds 10 to 15 kt. Seas 2 to 3 ft. Wave Detail: SE 2 ft
at 9 seconds and E 1 foot at 4 seconds. A chance of rain in the
afternoon.
.THU NIGHT...NE winds 5 to 10 kt. Seas around 2 ft. Wave Detail:
SE 2 ft at 9 seconds and E 1 foot at 3 seconds.
.FRI THROUGH SAT...SE winds 10 to 15 kt. Seas around 2 ft.
.SAT NIGHT...S 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.

$$

ANZ234-120000-
Buzzards Bay-
704 AM EDT Tue Mar 11 2025

.TODAY...S winds 5 to 10 kt. Gusts up to 20 kt this afternoon.
Seas 1 foot or less. Wave Detail: S 1 foot at 6 seconds and SE
1 foot at 9 seconds.
.TONIGHT...SW winds around 10 kt, becoming W with gusts up to
20 kt after midnight. Seas 1 foot or less, then around 2 ft after
midnight. Wave Detail: SW 1 foot at 4 seconds and SE 1 foot at
8 seconds, becoming E 1 foot at 4 seconds and SW 1 foot at
4 seconds.
.WED...N winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to
3 ft. Wave Detail: N 2 ft at 4 seconds and S 2 ft at 9 seconds.
.WED NIGHT...E winds 5 to 10 kt. Seas around 2 ft. Wave Detail: S
2 ft at 10 seconds and N 1 foot at 4 seconds.
.THU...E winds around 10 kt. Seas around 2 ft. Wave Detail: S
2 ft at 9 seconds and E 1 foot at 3 seconds.
.THU NIGHT...NE winds 5 to 10 kt. Seas around 2 ft. Wave Detail:
SE 2 ft at 9 seconds and E 1 foot at 2 seconds.
.FRI THROUGH SAT...SE winds 10 to 15 kt. Seas around 2 ft.
.SAT NIGHT...S 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.

$$

ANZ235-120000-
Rhode Island Sound-
704 AM EDT Tue Mar 11 2025

.TODAY...S winds 5 to 10 kt. Seas around 2 ft. Wave Detail: S
2 ft at 6 seconds.
.TONIGHT...SW winds around 10 kt, becoming W with gusts up to
20 kt after midnight. Seas 2 to 3 ft. Wave Detail: SW 2 ft at
5 seconds and S 2 ft at 9 seconds.
.WED...N winds 10 to 15 kt, becoming NE in the afternoon. Gusts
up to 20 kt. Seas 2 to 4 ft. Wave Detail: S 4 ft at 9 seconds and
N 2 ft at 3 seconds.
.WED NIGHT...E winds around 10 kt. Seas 3 to 4 ft. Wave Detail:
SE 4 ft at 9 seconds and N 1 foot at 4 seconds.
.THU AND THU NIGHT...NE winds 10 to 15 kt. Seas 3 to 4 ft. Wave
Detail: SE 4 ft at 9 seconds and E 2 ft at 4 seconds.
.FRI THROUGH SAT...SE winds 10 to 15 kt. Seas 2 to 3 ft. Wave
Detail: S 3 ft at 6 seconds and SE 3 ft at 9 seconds.
.SAT NIGHT...S winds 15 to 20 kt with gusts up to 25 kt. Seas
3 to 5 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.

$$

ANZ237-120000-
Block Island Sound-
704 AM EDT Tue Mar 11 2025

.TODAY...S winds 5 to 10 kt. Seas around 2 ft. Wave Detail: S
2 ft at 7 seconds.
.TONIGHT...SW winds around 10 kt, becoming NW with gusts up to
20 kt after midnight. Seas 2 to 3 ft. Wave Detail: S 2 ft at
9 seconds and W 1 foot at 2 seconds.
.WED...N winds 10 to 15 kt with gusts up to 20 kt, becoming E
5 to 10 kt in the afternoon. Seas 2 to 4 ft. Wave Detail: S 4 ft
at 9 seconds and N 2 ft at 3 seconds.
.WED NIGHT...E winds around 10 kt. Seas 3 to 4 ft. Wave Detail:
SE 4 ft at 9 seconds and NE 1 foot at 3 seconds.
.THU AND THU NIGHT...NE winds 10 to 15 kt. Seas 3 to 4 ft. Wave
Detail: SE 4 ft at 9 seconds and E 1 foot at 3 seconds.
.FRI THROUGH SAT...SE winds 5 to 10 kt. Seas 2 to 4 ft. Wave
Detail: SE 4 ft at 9 seconds and S 2 ft at 6 seconds.
.SAT NIGHT...S winds 15 to 20 kt with gusts up to 25 kt. Seas
3 to 5 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.

$$

ANZ230-120000-
Boston Harbor-
704 AM EDT Tue Mar 11 2025

...SMALL CRAFT ADVISORY IN EFFECT FROM 11 AM EDT THIS MORNING
THROUGH THIS EVENING...

.TODAY...S winds 10 to 15 kt, increasing to 15 to 20 kt this
afternoon. Gusts up to 25 kt. Waves around 2 ft.
.TONIGHT...SW winds 10 to 15 kt, becoming NW after midnight.
Gusts up to 25 kt. Waves around 2 ft.
.WED...N winds 15 to 20 kt, becoming NE 5 to 10 kt in the
afternoon. Gusts up to 25 kt. Waves around 2 ft.
.WED NIGHT...E winds 5 to 10 kt. Waves 1 foot or less.
.THU...SE winds 5 to 10 kt. Waves 1 foot or less.
.THU NIGHT...E winds 5 to 10 kt. Waves 1 foot or less.
.FRI THROUGH SAT...SE winds 10 to 15 kt. Waves around 2 ft.
.SAT NIGHT...S winds 15 to 20 kt with gusts up to 25 kt. Waves
around 2 ft. A chance of rain.

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.

$$

ANZ236-120000-
Narragansett Bay-
704 AM EDT Tue Mar 11 2025

.TODAY...S winds 5 to 10 kt, increasing to 10 to 15 kt with gusts
up to 20 kt this afternoon. Waves 1 foot or less, then around
2 ft this afternoon.
.TONIGHT...SW winds around 10 kt, becoming NW with gusts up to
20 kt after midnight. Waves around 2 ft.
.WED...N winds 10 to 15 kt with gusts up to 20 kt, becoming NE
5 to 10 kt in the afternoon. Waves 2 to 3 ft.
.WED NIGHT...E winds 5 to 10 kt. Waves 2 to 3 ft.
.THU...E winds 5 to 10 kt. Waves 2 to 4 ft.
.THU NIGHT...NE winds 5 to 10 kt. Waves 2 to 3 ft.
.FRI THROUGH SAT...SE winds 5 to 10 kt. Waves 2 to 3 ft.
.SAT NIGHT...S winds 15 to 20 kt with gusts up to 25 kt. Waves
3 to 5 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.

$$

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