National Weather Service Marine Forecast FZUS51 KBOX

FZUS51 KBOX 152304
CWFBOX

Coastal Waters Forecast for Massachusetts and Rhode Island
National Weather Service Boston/Norton MA
704 PM EDT Thu May 15 2025

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

ANZ200-161200
704 PM EDT Thu May 15 2025

Synopsis for Massachusetts and Rhode Island coastal waters

Sporadic showers and possibly some embedded thunder continue into the mid-afternoon hours before dissipating after sunset. Areas of dense fog developing over night with east/southeast winds. High pressure supports dry/quiet weather over the coastal waters tomorrow afternoon.

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ANZ250-161200
Coastal waters east of Ipswich Bay and the Stellwagen Bank National Marine Sanctuary
704 PM EDT Thu May 15 2025

TONIGHT
S winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: SE 2 ft at 7 seconds. Patchy fog. Vsby 1 NM or less.

FRI
S winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: SE 3 ft at 8 seconds. Patchy fog. Vsby 1 NM or less in the morning.

FRI NIGHT
S winds around 10 kt. Seas 2 to 3 ft. Wave Detail: SE 3 ft at 8 seconds. Patchy fog. Vsby 1 to 3 NM.

SAT
SE winds 10 to 15 kt. Seas 2 to 4 ft. Wave Detail: SE 3 ft at 8 seconds and SE 2 ft at 4 seconds. Patchy fog in the morning. A chance of showers in the afternoon. Vsby 1 to 3 NM in the morning.

SAT NIGHT
S winds 10 to 15 kt with gusts up to 20 kt, becoming SW after midnight. Seas 2 to 4 ft. Wave Detail: SE 3 ft at 7 seconds and S 2 ft at 4 seconds. Showers likely, mainly in the evening.

SUN AND SUN NIGHT
W winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to 3 ft. Wave Detail: E 3 ft at 6 seconds and W 2 ft at 3 seconds.

MON THROUGH TUE NIGHT
N winds 10 to 15 kt with gusts up to 20 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.

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ANZ251-161200
Massachusetts Bay and Ipswich Bay
704 PM EDT Thu May 15 2025

TONIGHT
S winds around 5 kt. Seas around 2 ft. Wave Detail: SE 2 ft at 7 seconds and E 1 foot at 3 seconds. Patchy fog. Vsby 1 NM or less.

FRI
SE winds 5 to 10 kt. Seas around 2 ft. Wave Detail: SE 2 ft at 7 seconds. Patchy fog. Vsby 1 NM or less in the morning.

FRI NIGHT
S winds 5 to 10 kt. Seas around 2 ft. Wave Detail: SE 2 ft at 8 seconds and SE 1 foot at 4 seconds. Patchy fog. Vsby 1 to 3 NM.

SAT
SE 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 4 seconds and SE 2 ft at 8 seconds. Patchy fog in the morning. A chance of showers in the afternoon. Vsby 1 to 3 NM in the morning.

SAT NIGHT
S winds around 10 kt, becoming SW after midnight. Seas 2 to 3 ft. Wave Detail: SE 2 ft at 4 seconds and SE 1 foot at 7 seconds. Showers likely in the evening.

SUN
W winds 5 to 10 kt. Seas around 2 ft. Wave Detail: E 2 ft at 6 seconds and W 1 foot at 2 seconds. A chance of showers in the afternoon.

SUN NIGHT
W winds 10 to 15 kt. Gusts up to 20 kt after midnight. Seas around 2 ft.

MON THROUGH TUE NIGHT
N 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.

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ANZ231-161200
Cape Cod Bay
704 PM EDT Thu May 15 2025

TONIGHT
S winds 5 to 10 kt. Seas around 2 ft this evening, then 1 foot or less. Wave Detail: SE 2 ft at 8 seconds and SE 1 foot at 2 seconds, becoming E 1 foot at 4 seconds and SE 1 foot at 7 seconds. Patchy fog. A slight chance of showers this evening. Vsby 1 NM or less.

FRI
S winds 5 to 10 kt. Seas 1 foot or less. Wave Detail: E 1 foot at 4 seconds and SE 1 foot at 7 seconds. Patchy fog. Vsby 1 NM or less in the morning.

FRI NIGHT
S winds 5 to 10 kt. Seas 1 foot or less. Wave Detail: SE 1 foot at 3 seconds and SE 1 foot at 8 seconds. Patchy fog. Vsby 1 to 3 NM.

SAT
S winds 5 to 10 kt. Seas 1 foot or less, then around 2 ft in the afternoon. Wave Detail: SE 1 foot at 2 seconds and SE 1 foot at 8 seconds, becoming SE 2 ft at 7 seconds and SE 1 foot at 3 seconds. Patchy fog in the morning. A chance of showers in the afternoon. Vsby 1 to 3 NM in the morning.

SAT NIGHT
SW winds 5 to 10 kt. Seas around 2 ft. Wave Detail: SE 2 ft at 7 seconds and SE 1 foot at 3 seconds. A chance of showers in the evening.

SUN AND SUN NIGHT
W winds 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 6 seconds.

MON THROUGH TUE NIGHT
N 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.

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ANZ254-161200
Coastal waters from Provincetown MA to Chatham MA to Nantucket MA out 20 nm
704 PM EDT Thu May 15 2025

SMALL CRAFT ADVISORY IN EFFECT UNTIL 1 AM EDT FRIDAY

TONIGHT
S winds 5 to 10 kt. Seas 3 to 4 ft. Wave Detail: S 4 ft at 8 seconds. Patchy fog. A slight chance of showers this evening. Vsby 1 NM or less.

FRI
S winds 5 to 10 kt. Seas 3 to 4 ft. Wave Detail: SE 4 ft at 8 seconds. Patchy fog. Vsby 1 NM or less in the morning.

FRI NIGHT
S winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: SE 3 ft at 8 seconds. Patchy fog. Vsby 1 to 3 NM.

SAT
S winds 5 to 10 kt. Seas 2 to 4 ft. Wave Detail: SE 3 ft at 7 seconds and SE 1 foot at 3 seconds. Patchy fog in the morning. A chance of showers in the afternoon. Vsby 1 to 3 NM in the morning.

SAT NIGHT
SW winds around 10 kt. Seas 3 to 4 ft. Wave Detail: S 3 ft at 7 seconds and SE 1 foot at 3 seconds. A chance of showers in the evening.

SUN AND SUN NIGHT
W winds 10 to 15 kt with gusts up to 20 kt. Seas 3 to 5 ft. Wave Detail: S 3 ft at 7 seconds and W 2 ft at 3 seconds.

MON THROUGH TUE NIGHT
N winds 10 to 15 kt with gusts up to 20 kt. Seas 3 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.

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ANZ255-161200
Coastal Waters extending out to 25 nm South of Marthas Vineyard and Nantucket
704 PM EDT Thu May 15 2025

SMALL CRAFT ADVISORY IN EFFECT UNTIL 1 AM EDT FRIDAY

TONIGHT
S winds 5 to 10 kt. Seas 3 to 4 ft. Wave Detail: S 4 ft at 8 seconds. Patchy fog. A slight chance of showers. Vsby 1 NM or less.

FRI
SW winds 5 to 10 kt. Seas 3 to 4 ft. Wave Detail: S 4 ft at 8 seconds. Patchy fog. Vsby 1 NM or less in the morning.

FRI NIGHT
S winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: SE 3 ft at 7 seconds. Patchy fog. Vsby 1 to 3 NM.

SAT
S winds 10 to 15 kt. Seas 2 to 4 ft. Wave Detail: SE 3 ft at 7 seconds. Patchy fog in the morning. A chance of showers in the afternoon. Vsby 1 to 3 NM in the morning.

SAT NIGHT
SW winds 10 to 15 kt. Seas 3 to 4 ft. Wave Detail: S 4 ft at 7 seconds. A chance of showers in the evening.

SUN AND SUN NIGHT
W winds 10 to 15 kt with gusts up to 20 kt. Seas 3 to 5 ft. Wave Detail: SW 5 ft at 6 seconds.

MON
NW winds 10 to 15 kt with gusts up to 20 kt. Seas 3 to 5 ft.

MON NIGHT THROUGH TUE NIGHT
N winds 10 to 15 kt with gusts up to 20 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.

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ANZ256-161200
Coastal Waters from Montauk NY to Marthas Vineyard extending out to 20 nm South of Block Island
704 PM EDT Thu May 15 2025

SMALL CRAFT ADVISORY IN EFFECT UNTIL 1 AM EDT FRIDAY

TONIGHT
S winds around 5 kt. Seas 3 to 5 ft. Wave Detail: S 5 ft at 8 seconds. Patchy fog. A slight chance of showers. Vsby 1 NM or less.

FRI
SW winds 5 to 10 kt. Seas 3 to 4 ft. Wave Detail: SE 4 ft at 8 seconds. Patchy fog. Vsby 1 NM or less in the morning.

FRI NIGHT
S winds 5 to 10 kt. Seas around 3 ft. Wave Detail: SE 3 ft at 7 seconds. Patchy fog. Vsby 1 to 3 NM.

SAT
S winds 5 to 10 kt, increasing to 10 to 15 kt in the afternoon. Seas 3 to 4 ft. Wave Detail: SE 3 ft at 7 seconds. Patchy fog in the morning. A chance of showers in the afternoon. Vsby 1 to 3 NM in the morning.

SAT NIGHT
SW winds 10 to 15 kt. Seas 3 to 4 ft. Wave Detail: S 4 ft at 7 seconds. A chance of showers in the evening.

SUN AND SUN NIGHT
W winds 15 to 20 kt. Seas 4 to 5 ft. Wave Detail: SW 4 ft at 6 seconds.

MON
NW winds 10 to 15 kt with gusts up to 20 kt. Seas 3 to 5 ft.

MON NIGHT THROUGH TUE NIGHT
N 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.

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ANZ232-161200
Nantucket Sound
704 PM EDT Thu May 15 2025

TONIGHT
S winds around 5 kt. Seas around 2 ft. Wave Detail: S 2 ft at 8 seconds and E 1 foot at 4 seconds. Patchy fog. A slight chance of showers. Vsby 1 NM or less.

FRI
SW winds 5 to 10 kt. Seas around 2 ft. Wave Detail: S 2 ft at 8 seconds and SW 1 foot at 2 seconds. Patchy fog in the morning with vsby 1 NM or less.

FRI NIGHT
S winds 5 to 10 kt. Seas around 2 ft in the evening, then 1 foot or less. Wave Detail: SE 2 ft at 6 seconds and SW 1 foot at 2 seconds, becoming SW 1 foot at 2 seconds and SE 1 foot at 6 seconds. Patchy fog. Vsby 1 to 3 NM.

SAT
S winds 5 to 10 kt. Seas around 2 ft. Wave Detail: SE 1 foot at 3 seconds and SE 1 foot at 7 seconds. Patchy fog in the morning. A chance of showers in the afternoon. Vsby 1 to 3 NM in the morning.

SAT NIGHT
SW winds around 10 kt. Seas around 2 ft. Wave Detail: S 2 ft at 7 seconds and S 1 foot at 4 seconds. A chance of showers in the evening.

SUN AND SUN NIGHT
W winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to 3 ft. Wave Detail: W 2 ft at 3 seconds and S 2 ft at 7 seconds.

MON THROUGH TUE NIGHT
N 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.

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ANZ233-161200
Vineyard Sound
704 PM EDT Thu May 15 2025

TONIGHT
S winds around 5 kt. Seas 2 to 3 ft. Wave Detail: S 2 ft at 8 seconds and E 1 foot at 3 seconds. Patchy fog. Vsby 1 NM or less.

FRI
SW winds 5 to 10 kt. Seas around 2 ft. Wave Detail: S 2 ft at 7 seconds and SW 1 foot at 2 seconds. Patchy fog in the morning with vsby 1 NM or less.

FRI NIGHT
S winds 5 to 10 kt. Seas around 2 ft. Wave Detail: S 2 ft at 7 seconds and SW 1 foot at 2 seconds. Patchy fog. Vsby 1 to 3 NM.

SAT
S winds 5 to 10 kt. Seas around 2 ft. Wave Detail: S 2 ft at 7 seconds and SE 1 foot at 3 seconds. Patchy fog in the morning. A chance of showers in the afternoon. Vsby 1 to 3 NM in the morning.

SAT NIGHT
SW winds around 10 kt. Seas around 2 ft. Wave Detail: S 2 ft at 7 seconds and S 1 foot at 3 seconds. A chance of showers in the evening.

SUN AND SUN NIGHT
W winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to 3 ft. Wave Detail: SW 3 ft at 7 seconds and SW 2 ft at 4 seconds.

MON THROUGH TUE NIGHT
N 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.

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ANZ234-161200
Buzzards Bay
704 PM EDT Thu May 15 2025

TONIGHT
S winds around 5 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.

FRI
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. Patchy fog in the morning with vsby 1 NM or less.

FRI NIGHT
S winds 5 to 10 kt. Seas around 2 ft in the evening, then 1 foot or less. Wave Detail: S 2 ft at 7 seconds and SW 1 foot at 2 seconds, becoming S 1 foot at 3 seconds and S 1 foot at 7 seconds. Patchy fog. Vsby 1 to 3 NM.

SAT
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 S 1 foot at 7 seconds, becoming S 2 ft at 7 seconds and S 1 foot at 3 seconds. Patchy fog in the morning. A chance of showers in the afternoon. Vsby 1 to 3 NM in the morning.

SAT NIGHT
SW winds 5 to 10 kt. Seas around 2 ft. Wave Detail: S 2 ft at 7 seconds and S 1 foot at 4 seconds. A chance of showers in the evening.

SUN AND SUN NIGHT
W 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 SW 2 ft at 7 seconds.

MON THROUGH TUE NIGHT
N 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.

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ANZ235-161200
Rhode Island Sound
704 PM EDT Thu May 15 2025

TONIGHT
S winds around 5 kt. Seas 2 to 4 ft. Wave Detail: S 4 ft at 8 seconds. Patchy fog. A slight chance of showers this evening. Vsby 1 NM or less.

FRI
SW 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 in the morning.

FRI NIGHT
S winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: SE 3 ft at 7 seconds. Patchy fog. Vsby 1 to 3 NM.

SAT
S winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: SE 3 ft at 7 seconds and S 1 foot at 2 seconds. A chance of showers. Patchy fog in the morning with vsby 1 to 3 NM.

SAT NIGHT
SW winds around 10 kt. Seas around 3 ft. Wave Detail: S 3 ft at 7 seconds. A chance of showers in the evening.

SUN AND SUN NIGHT
W winds 10 to 15 kt with gusts up to 20 kt. Seas 3 to 4 ft. Wave Detail: S 4 ft at 7 seconds and W 2 ft at 5 seconds.

MON AND MON NIGHT
NW winds 10 to 15 kt. Gusts up to 20 kt. Seas 2 to 4 ft.

TUE AND TUE NIGHT
N winds 10 to 15 kt. 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.

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ANZ237-161200
Block Island Sound
704 PM EDT Thu May 15 2025

TONIGHT
S winds around 5 kt. Seas 2 to 4 ft. Wave Detail: S 4 ft at 8 seconds. Patchy fog. A slight chance of showers this evening. Vsby 1 NM or less.

FRI
SW winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: S 3 ft at 7 seconds. Patchy fog in the morning with vsby 1 NM or less.

FRI NIGHT
S winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: SE 3 ft at 8 seconds. Patchy fog. Vsby 1 to 3 NM.

SAT
S winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: SE 3 ft at 7 seconds. A chance of showers. Patchy fog in the morning with vsby 1 to 3 NM.

SAT NIGHT
SW winds around 10 kt. Seas 2 to 3 ft. Wave Detail: S 3 ft at 7 seconds and W 1 foot at 3 seconds. A chance of showers in the evening.

SUN AND SUN NIGHT
W winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to 4 ft. Wave Detail: S 3 ft at 7 seconds and W 2 ft at 3 seconds.

MON THROUGH TUE NIGHT
N 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.

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ANZ230-161200
Boston Harbor
704 PM EDT Thu May 15 2025

TONIGHT
SE winds around 5 kt. Waves around 2 ft this evening, then 1 foot or less. Patchy fog. A slight chance of showers this evening. Vsby 1 NM or less.

FRI
SE winds 5 to 10 kt. Waves 1 foot or less, then around 2 ft in the afternoon. Patchy fog in the morning with vsby 1 NM or less.

FRI NIGHT
S winds 5 to 10 kt. Waves around 2 ft. Patchy fog after midnight with vsby 1 to 3 NM.

SAT
SE winds 5 to 10 kt. Waves 1 foot or less, then around 2 ft in the afternoon. Patchy fog in the morning. A chance of showers in the afternoon. Vsby 1 to 3 NM in the morning.

SAT NIGHT
S winds 5 to 10 kt, becoming SW after midnight. Waves around 2 ft in the evening, then 1 foot or less. Showers likely, mainly in the evening.

SUN AND SUN NIGHT
W winds 10 to 15 kt with gusts up to 20 kt. Waves around 2 ft. A chance of showers through the night.

MON THROUGH TUE NIGHT
N winds 10 to 15 kt with gusts up to 20 kt. Waves 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.

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ANZ236-161200
Narragansett Bay
704 PM EDT Thu May 15 2025

TONIGHT
S winds around 5 kt. Waves 2 to 3 ft. Patchy fog. A slight chance of showers this evening. Vsby 1 NM or less.

FRI
S winds 5 to 10 kt. Waves around 2 ft. Patchy fog in the morning with vsby 1 NM or less.

FRI NIGHT
S winds 5 to 10 kt. Waves around 2 ft. Patchy fog. Vsby 1 to 3 NM.

SAT
S winds 5 to 10 kt. Waves 2 to 3 ft. Patchy fog in the morning. A chance of showers in the afternoon. Vsby 1 to 3 NM in the morning.

SAT NIGHT
SW winds 5 to 10 kt. Waves 2 to 3 ft. A chance of showers in the evening.

SUN AND SUN NIGHT
NW winds 10 to 15 kt with gusts up to 20 kt. Waves 2 to 4 ft.

MON THROUGH TUE NIGHT
N 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.

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