National Weather Service Marine Forecast FZUS51 KBOX

FZUS51 KBOX 180805
CWFBOX

Coastal Waters Forecast for Massachusetts and Rhode Island
National Weather Service Boston/Norton MA
404 AM EDT Mon May 18 2026

Coastal waters from the Merrimack River MA to Watch Hill RI out to 60 NM

ANZ200-182100
404 AM EDT Mon May 18 2026

Synopsis for Massachusetts and Rhode Island coastal waters

A weak cold front will move into the southern waters this morning before lifting back N as a warm front later today and this evening. Gusty SW winds will develop Tue. A strong cold front will cross the waters late Wed and Wed evening. Strong high pres builds over the Gt Lakes Thu and moves into the waters Fri. The high moves offshore by Sat as a frontal boundary approaches from the S.

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ANZ250-182100
Coastal waters east of Ipswich Bay and the Stellwagen Bank National Marine Sanctuary
404 AM EDT Mon May 18 2026

TODAY
E winds 5 to 10 kt, becoming SE 10 to 15 kt with gusts up to 20 kt this afternoon. Seas 2 to 3 ft. Wave Detail: E 2 ft at 3 seconds and SE 2 ft at 8 seconds.

TONIGHT
S winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to 3 ft. Wave Detail: SE 3 ft at 7 seconds and S 2 ft at 3 seconds.

TUE
SW winds 10 to 15 kt with gusts up to 20 kt, becoming S 15 to 20 kt with gusts up to 30 kt in the afternoon. Seas 2 to 4 ft. Wave Detail: SW 3 ft at 4 seconds and SE 2 ft at 7 seconds.

TUE NIGHT
SW winds 15 to 20 kt with gusts up to 30 kt. Seas 3 to 5 ft. Wave Detail: SW 3 ft at 4 seconds and SE 3 ft at 7 seconds.

WED
SW winds 10 to 15 kt with gusts up to 25 kt. Seas 2 to 4 ft. Wave Detail: SW 3 ft at 4 seconds and SE 3 ft at 8 seconds. Showers likely in the afternoon.

WED NIGHT
W winds around 15 kt, becoming NW after midnight. Gusts up to 20 kt. Seas 2 to 4 ft. Wave Detail: N 3 ft at 4 seconds and SE 2 ft at 8 seconds. Showers likely in the evening.

THU THROUGH FRI
E winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to 3 ft.

FRI NIGHT
S winds 5 to 10 kt. Seas 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.

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ANZ251-182100
Massachusetts Bay and Ipswich Bay
404 AM EDT Mon May 18 2026

TODAY
E winds 5 to 10 kt, becoming SE 10 to 15 kt with gusts up to 20 kt this afternoon. Seas around 2 ft. Wave Detail: E 2 ft at 3 seconds and W 1 foot at 2 seconds.

TONIGHT
S winds 10 to 15 kt. Seas around 2 ft. Wave Detail: SE 2 ft at 4 seconds and SE 2 ft at 8 seconds.

TUE
SW winds 10 to 15 kt. Gusts up to 25 kt in the afternoon. Seas 2 to 3 ft. Wave Detail: S 2 ft at 3 seconds and SE 2 ft at 8 seconds.

TUE NIGHT
SW winds 15 to 20 kt. Seas 2 to 3 ft. Wave Detail: SW 2 ft at 3 seconds and SE 2 ft at 7 seconds.

WED
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 8 seconds. Showers likely in the afternoon.

WED NIGHT
NW winds 10 to 15 kt. Gusts up to 20 kt in the evening. Seas around 2 ft. Wave Detail: NW 2 ft at 3 seconds and SE 1 foot at 8 seconds. Showers likely in the evening.

THU THROUGH FRI
E winds 10 to 15 kt with gusts up to 20 kt. Seas around 2 ft.

FRI NIGHT
S winds 5 to 10 kt. Seas 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.

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ANZ231-182100
Cape Cod Bay
404 AM EDT Mon May 18 2026

TODAY
SE winds 5 to 10 kt. Seas 1 foot or less, then around 2 ft this afternoon. Wave Detail: E 1 foot at 2 seconds and W 1 foot at 3 seconds, becoming SE 1 foot at 2 seconds and SW 1 foot at 3 seconds.

TONIGHT
S winds 10 to 15 kt. Gusts up to 20 kt after midnight. Seas around 2 ft. Wave Detail: S 1 foot at 2 seconds and E 1 foot at 3 seconds.

TUE
SW winds 10 to 15 kt, increasing to 15 to 20 kt in the afternoon. Gusts up to 25 kt. Seas 2 to 4 ft. Wave Detail: SW 2 ft at 3 seconds and NE 1 foot at 4 seconds.

TUE NIGHT
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 SE 1 foot at 9 seconds.

WED
SW winds 10 to 15 kt with gusts up to 25 kt. Seas 2 to 4 ft. Wave Detail: SW 2 ft at 3 seconds and SE 1 foot at 3 seconds. Showers likely in the afternoon.

WED NIGHT
W winds 10 to 15 kt, becoming NW after midnight. Gusts up to 20 kt. Seas 2 to 3 ft. Wave Detail: W 2 ft at 3 seconds and N 1 foot at 3 seconds. A chance of showers in the evening.

THU THROUGH FRI
E winds 10 to 15 kt with gusts up to 20 kt. Seas around 2 ft.

FRI NIGHT
S winds 5 to 10 kt. Seas 1 foot or less. 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.

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ANZ254-182100
Coastal waters from Provincetown MA to Chatham MA to Nantucket MA out 20 NM
404 AM EDT Mon May 18 2026

TODAY
E winds around 10 kt, becoming SE this afternoon. Seas 2 to 3 ft. Wave Detail: S 3 ft at 8 seconds and SW 2 ft at 5 seconds.

TONIGHT
SW winds 10 to 15 kt. Gusts up to 20 kt after midnight. Seas 2 to 3 ft. Wave Detail: SW 3 ft at 4 seconds and SE 3 ft at 7 seconds. Patchy fog. Vsby 1 NM or less.

TUE
SW winds 15 to 20 kt with gusts up to 25 kt. Seas 3 to 5 ft. Wave Detail: SW 5 ft at 6 seconds and SE 2 ft at 9 seconds. Patchy fog. Vsby 1 NM or less, increasing to 1 to 3 NM in the afternoon.

TUE NIGHT
SW winds 15 to 20 kt with gusts up to 30 kt. Seas 4 to 6 ft. Wave Detail: S 5 ft at 7 seconds and E 1 foot at 14 seconds.

WED
SW winds 15 to 20 kt with gusts up to 25 kt. Seas 4 to 6 ft. Wave Detail: S 5 ft at 7 seconds. A chance of showers in the afternoon.

WED NIGHT
W winds 15 to 20 kt, becoming NW 10 to 15 kt after midnight. Gusts up to 25 kt. Seas 4 to 6 ft, subsiding to 3 to 4 ft after midnight. Wave Detail: SW 5 ft at 6 seconds and SE 3 ft at 9 seconds, becoming NW 4 ft at 4 seconds and S 2 ft at 8 seconds. A chance of showers.

THU THROUGH FRI
E winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to 4 ft.

FRI NIGHT
S winds 5 to 10 kt. Seas 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.

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ANZ255-182100
Coastal Waters extending out to 25 NM South of Marthas Vineyard and Nantucket
404 AM EDT Mon May 18 2026

TODAY
E winds 5 to 10 kt, becoming SE this afternoon. Seas 3 to 4 ft. Wave Detail: SW 4 ft at 7 seconds and NE 1 foot at 8 seconds.

TONIGHT
SW winds 10 to 15 kt. Gusts up to 20 kt after midnight. Seas 2 to 4 ft. Wave Detail: S 3 ft at 7 seconds and NE 1 foot at 3 seconds. Patchy fog. Vsby 1 NM or less.

TUE
SW winds 15 to 20 kt with gusts up to 25 kt. Seas 4 to 6 ft. Wave Detail: SW 6 ft at 6 seconds and SE 2 ft at 9 seconds. Patchy fog. Vsby 1 NM or less, increasing to 1 to 3 NM in the afternoon.

TUE NIGHT
SW winds around 20 kt with gusts up to 25 kt. Seas 5 to 7 ft. Wave Detail: SW 7 ft at 7 seconds and E 4 ft at 10 seconds. Patchy fog in the evening with vsby 1 NM or less.

WED
SW winds around 20 kt with gusts up to 25 kt. Seas 5 to 7 ft. Wave Detail: SW 7 ft at 7 seconds and SE 1 foot at 3 seconds.

WED NIGHT
SW winds 15 to 20 kt with gusts up to 25 kt, becoming NW 10 to 15 kt after midnight. Seas 5 to 7 ft, subsiding to 3 to 5 ft after midnight. Wave Detail: SW 6 ft at 7 seconds and E 1 foot at 10 seconds, becoming SW 5 ft at 7 seconds and N 2 ft at 2 seconds. A chance of showers.

THU AND THU NIGHT
NE winds 10 to 15 kt with gusts up to 20 kt, becoming E 5 to 10 kt. Seas 2 to 4 ft.

FRI
E winds 5 to 10 kt. Seas around 2 ft.

FRI NIGHT
SE winds 5 to 10 kt. Seas 2 to 3 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.

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ANZ256-182100
Coastal Waters from Montauk NY to Marthas Vineyard extending out to 20 NM South of Block Island
404 AM EDT Mon May 18 2026

TODAY
E winds 5 to 10 kt, becoming SE this afternoon. Seas 3 to 4 ft. Wave Detail: S 4 ft at 8 seconds and SW 3 ft at 7 seconds.

TONIGHT
SW winds 10 to 15 kt. Gusts up to 20 kt after midnight. Seas 3 to 4 ft. Wave Detail: SW 3 ft at 7 seconds and S 3 ft at 8 seconds. Patchy fog. Vsby 1 NM or less.

TUE
SW winds 15 to 20 kt with gusts up to 25 kt. Seas 4 to 6 ft. Wave Detail: SW 5 ft at 6 seconds and SE 2 ft at 9 seconds. Patchy fog. Vsby 1 NM or less, increasing to 1 to 3 NM in the afternoon.

TUE NIGHT
SW winds 20 to 25 kt with gusts up to 30 kt. Seas 5 to 7 ft. Wave Detail: S 7 ft at 7 seconds. Patchy fog in the evening with vsby 1 to 3 NM.

WED
SW winds 15 to 20 kt with gusts up to 25 kt. Seas 5 to 7 ft. Wave Detail: SW 6 ft at 7 seconds and S 5 ft at 9 seconds. A chance of showers in the afternoon.

WED NIGHT
W winds 15 to 20 kt with gusts up to 25 kt, becoming NW 10 to 15 kt after midnight. Seas 4 to 6 ft. Wave Detail: SW 6 ft at 7 seconds and SE 2 ft at 9 seconds. A chance of showers.

THU AND THU NIGHT
NE winds 10 to 15 kt, becoming E 5 to 10 kt. Seas 2 to 4 ft.

FRI
E winds 5 to 10 kt. Seas around 2 ft.

FRI NIGHT
SE winds 5 to 10 kt. Seas 2 to 3 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.

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ANZ232-182100
Nantucket Sound
404 AM EDT Mon May 18 2026

TODAY
E winds around 10 kt, becoming SE this afternoon. Seas around 2 ft. Wave Detail: E 1 foot at 3 seconds and SW 1 foot at 5 seconds.

TONIGHT
SW winds 10 to 15 kt. Gusts up to 20 kt after midnight. Seas around 2 ft. Wave Detail: SW 2 ft at 4 seconds and E 1 foot at 3 seconds. Patchy fog. Vsby 1 to 3 NM, decreasing to 1 NM or less after midnight.

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 4 seconds. Patchy fog. Vsby 1 NM or less, increasing to 1 to 3 NM in the afternoon.

TUE NIGHT
SW winds 15 to 20 kt with gusts up to 25 kt. Seas 3 to 4 ft. Wave Detail: SW 3 ft at 4 seconds and SE 1 foot at 9 seconds. Patchy fog in the evening with vsby 1 NM or less.

WED
SW winds 15 to 20 kt with gusts up to 25 kt. Seas 3 to 4 ft. Wave Detail: SW 3 ft at 4 seconds and SE 1 foot at 3 seconds. A chance of showers in the afternoon.

WED NIGHT
W winds 15 to 20 kt with gusts up to 25 kt, becoming NW 10 to 15 kt after midnight. Seas 2 to 4 ft. Wave Detail: W 3 ft at 4 seconds and N 2 ft at 2 seconds. A chance of showers.

THU THROUGH FRI
E winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to 3 ft.

FRI NIGHT
SE winds 5 to 10 kt. Seas 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.

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ANZ233-182100
Vineyard Sound
404 AM EDT Mon May 18 2026

TODAY
E winds around 10 kt, becoming SE this afternoon. Seas 2 to 3 ft. Wave Detail: SW 2 ft at 7 seconds and SE 2 ft at 8 seconds.

TONIGHT
SW winds 10 to 15 kt. Seas 2 to 3 ft. Wave Detail: SW 3 ft at 6 seconds and SE 3 ft at 9 seconds. Patchy fog. Vsby 1 to 3 NM, decreasing to 1 NM or less after midnight.

TUE
SW winds 15 to 20 kt with gusts up to 25 kt. Seas 2 to 4 ft. Wave Detail: SW 4 ft at 6 seconds and SE 2 ft at 9 seconds. Patchy fog. Vsby 1 NM or less, increasing to 1 to 3 NM in the afternoon.

TUE NIGHT
SW winds 15 to 20 kt with gusts up to 25 kt. Seas 3 to 5 ft. Wave Detail: SW 5 ft at 6 seconds and E 2 ft at 6 seconds.

WED
SW winds 15 to 20 kt with gusts up to 25 kt. Seas 3 to 5 ft. Wave Detail: SW 5 ft at 7 seconds and E 2 ft at 5 seconds. A chance of showers in the afternoon.

WED NIGHT
W winds 15 to 20 kt, becoming NW around 10 kt after midnight. Seas 3 to 5 ft, subsiding to 2 to 3 ft after midnight. Wave Detail: SW 5 ft at 7 seconds and E 1 foot at 9 seconds, becoming SW 3 ft at 7 seconds and N 2 ft at 2 seconds. A chance of showers.

THU THROUGH FRI
E winds 10 to 15 kt. Seas 2 to 3 ft.

FRI NIGHT
SE winds 5 to 10 kt. Seas 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.

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ANZ234-182100
Buzzards Bay
404 AM EDT Mon May 18 2026

TODAY
E winds 5 to 10 kt, becoming SE this afternoon. Seas around 2 ft. Wave Detail: S 2 ft at 8 seconds and E 1 foot at 2 seconds.

TONIGHT
SW winds 10 to 15 kt. Seas around 2 ft. Wave Detail: S 2 ft at 4 seconds and SE 2 ft at 9 seconds. Patchy fog after midnight with vsby 1 NM or less.

TUE
SW winds 10 to 15 kt, increasing to 15 to 20 kt in the afternoon. Gusts up to 25 kt. Seas 2 to 4 ft. Wave Detail: SW 3 ft at 5 seconds and SE 2 ft at 8 seconds. Patchy fog in the morning with vsby 1 to 3 NM.

TUE NIGHT
SW winds 15 to 20 kt with gusts up to 25 kt. Seas 3 to 4 ft. Wave Detail: S 3 ft at 6 seconds and SE 1 foot at 18 seconds.

WED
SW winds 15 to 20 kt with gusts up to 25 kt. Seas 2 to 4 ft. Wave Detail: S 4 ft at 6 seconds. A chance of showers in the afternoon.

WED NIGHT
W winds 10 to 15 kt with gusts up to 20 kt, becoming NW after midnight. Seas 2 to 4 ft. Wave Detail: SW 3 ft at 6 seconds and N 2 ft at 2 seconds. A chance of showers in the evening.

THU THROUGH FRI
E winds 5 to 10 kt. Seas around 2 ft.

FRI NIGHT
SE winds 5 to 10 kt. Seas 1 foot or less. 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.

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ANZ235-182100
Rhode Island Sound
404 AM EDT Mon May 18 2026

TODAY
E winds around 10 kt, becoming SE this afternoon. Seas 2 to 3 ft. Wave Detail: S 3 ft at 7 seconds and E 1 foot at 14 seconds.

TONIGHT
SW winds 10 to 15 kt. Gusts up to 20 kt after midnight. Seas 2 to 3 ft. Wave Detail: S 3 ft at 8 seconds and E 1 foot at 3 seconds. Patchy fog. Vsby 1 NM or less.

TUE
SW winds 15 to 20 kt with gusts up to 25 kt. Seas 3 to 5 ft. Wave Detail: SW 5 ft at 6 seconds and SE 2 ft at 9 seconds. Patchy fog. Vsby 1 NM or less, increasing to 1 to 3 NM in the afternoon.

TUE NIGHT
SW winds 15 to 20 kt with gusts up to 25 kt. Seas 4 to 6 ft. Wave Detail: S 6 ft at 7 seconds. Patchy fog in the evening with vsby 1 to 3 NM.

WED
SW winds 15 to 20 kt with gusts up to 25 kt. Seas 4 to 6 ft. Wave Detail: S 6 ft at 7 seconds. A chance of showers in the afternoon.

WED NIGHT
W winds 15 to 20 kt, becoming NW 10 to 15 kt after midnight. Seas 3 to 5 ft. Wave Detail: S 5 ft at 7 seconds and NE 1 foot at 2 seconds. A chance of showers in the evening.

THU AND THU NIGHT
NE winds 10 to 15 kt, becoming E 5 to 10 kt. Seas 2 to 4 ft.

FRI
E winds 5 to 10 kt. Seas around 2 ft.

FRI NIGHT
SE winds 5 to 10 kt. Seas 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.

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ANZ237-182100
Block Island Sound
404 AM EDT Mon May 18 2026

TODAY
E winds 5 to 10 kt, becoming SE this afternoon. Seas 2 to 3 ft. Wave Detail: S 3 ft at 8 seconds and SW 2 ft at 7 seconds.

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

TUE
SW winds 10 to 15 kt, increasing to 15 to 20 kt in the afternoon. Gusts up to 25 kt. Seas 2 to 4 ft. Wave Detail: SW 4 ft at 4 seconds and SE 2 ft at 9 seconds.

TUE NIGHT
SW winds 15 to 20 kt with gusts up to 25 kt. Seas 3 to 5 ft. Wave Detail: SW 4 ft at 5 seconds and SE 4 ft at 8 seconds.

WED
SW winds 10 to 15 kt, increasing to 15 to 20 kt in the afternoon. Gusts up to 25 kt. Seas 3 to 5 ft. Wave Detail: SW 4 ft at 7 seconds and SE 1 foot at 14 seconds. A chance of showers in the afternoon.

WED NIGHT
W winds 10 to 15 kt with gusts up to 20 kt, becoming NW after midnight. Seas 3 to 5 ft. Wave Detail: SW 3 ft at 6 seconds and NE 1 foot at 2 seconds. A chance of showers in the evening.

THU THROUGH FRI
E winds 5 to 10 kt. Seas 2 to 3 ft.

FRI NIGHT
SE winds 5 to 10 kt. Seas 2 to 3 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.

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ANZ230-182100
Boston Harbor
404 AM EDT Mon May 18 2026

TODAY
E 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
S winds around 10 kt. Waves around 2 ft.

TUE
SW winds 10 to 15 kt. Gusts up to 20 kt in the afternoon. Waves around 2 ft.

TUE NIGHT
SW winds 10 to 15 kt with gusts up to 20 kt. Waves around 2 ft.

WED
W winds 10 to 15 kt with gusts up to 20 kt. Waves around 2 ft. Showers in the afternoon.

WED NIGHT
NW winds 10 to 15 kt. Gusts up to 20 kt in the evening. Waves around 2 ft. Showers likely in the evening.

THU THROUGH FRI
E winds 10 to 15 kt. Waves around 2 ft.

FRI NIGHT
S winds 5 to 10 kt. Waves 1 foot or less. 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.

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ANZ236-182100
Narragansett Bay
404 AM EDT Mon May 18 2026

TODAY
E winds 5 to 10 kt, becoming SE this afternoon. Waves around 2 ft.

TONIGHT
S winds around 10 kt. Waves around 2 ft. Patchy fog after midnight with vsby 1 NM or less.

TUE
SW winds 10 to 15 kt with gusts up to 25 kt. Waves 2 to 3 ft.

TUE NIGHT
SW winds 10 to 15 kt with gusts up to 20 kt. Waves 2 to 3 ft.

WED
SW winds 10 to 15 kt, increasing to 15 to 20 kt in the afternoon. Gusts up to 25 kt. Waves 2 to 4 ft. Showers likely in the afternoon.

WED NIGHT
NW winds 10 to 15 kt. Gusts up to 20 kt in the evening. Waves 2 to 3 ft. A chance of showers in the evening.

THU THROUGH FRI
E winds 10 to 15 kt. Waves around 2 ft.

FRI NIGHT
SE winds 5 to 10 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.

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ANZ280-182100
Ocean Waters from the Merrimack River to Plymouth from 40 to 60 NM
404 AM EDT Mon May 18 2026

TODAY
E winds around 10 kt, becoming SE this afternoon. Seas around 3 ft. Wave Detail: S 3 ft at 8 seconds and NE 1 foot at 3 seconds.

TONIGHT
S winds 10 to 15 kt with gusts up to 20 kt. Seas 3 to 4 ft. Wave Detail: SW 3 ft at 4 seconds and SE 3 ft at 7 seconds. Patchy fog after midnight with vsby 1 NM or less.

TUE
SW winds around 15 kt with gusts up to 20 kt, increasing to 20 to 25 kt with gusts up to 30 kt in the afternoon. Seas 3 to 4 ft, building to 4 to 6 ft in the afternoon. Wave Detail: SW 3 ft at 5 seconds and SE 2 ft at 9 seconds, becoming S 5 ft at 5 seconds and SE 3 ft at 9 seconds. Patchy fog in the morning with vsby 1 NM or less.

TUE NIGHT
SW winds 20 to 25 kt, diminishing to 15 to 20 kt after midnight. Gusts up to 30 kt. Seas 5 to 7 ft. Wave Detail: SW 6 ft at 6 seconds and S 6 ft at 9 seconds.

WED
SW winds 15 to 20 kt with gusts up to 25 kt. Seas 4 to 6 ft. Wave Detail: S 4 ft at 5 seconds. A chance of showers in the afternoon.

WED NIGHT
W winds 15 to 20 kt, becoming NW after midnight. Gusts up to 25 kt. Seas 4 to 6 ft. Wave Detail: S 4 ft at 7 seconds and W 3 ft at 4 seconds. A chance of showers in the evening.

THU AND THU NIGHT
NW winds 10 to 15 kt with gusts up to 20 kt, diminishing to 5 to 10 kt. Seas 2 to 4 ft.

FRI AND FRI NIGHT
NW winds 5 to 10 kt, becoming S. 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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ANZ281-182100
Ocean Waters from Provincetown to Nantucket from 20 to 60 NM
404 AM EDT Mon May 18 2026

TODAY
E winds around 10 kt, becoming SE this afternoon. Seas 3 to 4 ft. Wave Detail: S 4 ft at 8 seconds and SW 3 ft at 7 seconds.

TONIGHT
S winds 10 to 15 kt with gusts up to 20 kt. Seas 3 to 4 ft. Wave Detail: S 3 ft at 7 seconds and NE 1 foot at 4 seconds. Patchy fog. Vsby 1 NM or less.

TUE
SW winds 15 to 20 kt with gusts up to 30 kt. Seas 4 to 6 ft. Wave Detail: SW 6 ft at 6 seconds and SE 2 ft at 9 seconds. Patchy fog. Vsby 1 NM or less, increasing to 1 to 3 NM in the afternoon.

TUE NIGHT
SW winds 20 to 25 kt with gusts up to 30 kt. Seas around 6 ft. Wave Detail: SW 6 ft at 7 seconds and SE 4 ft at 9 seconds. Patchy fog in the evening with vsby 1 to 3 NM.

WED
SW winds around 20 kt with gusts up to 30 kt. Seas 6 to 7 ft. Wave Detail: SW 6 ft at 7 seconds and SE 1 foot at 9 seconds. A chance of showers in the afternoon.

WED NIGHT
SW winds 15 to 20 kt, becoming NW after midnight. Gusts up to 25 kt. Seas 5 to 7 ft. Wave Detail: SW 6 ft at 7 seconds and SE 2 ft at 9 seconds. A chance of showers.

THU THROUGH FRI
E winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to 4 ft.

FRI NIGHT
SE winds 5 to 10 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.

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ANZ282-182100
Ocean Waters from Marthas Vineyard to Nantucket from 25 to 60 NM
404 AM EDT Mon May 18 2026

TODAY
SE winds 5 to 10 kt. Seas 3 to 4 ft. Wave Detail: SW 3 ft at 7 seconds and SE 3 ft at 8 seconds. Patchy fog this morning with vsby 1 NM or less.

TONIGHT
SW winds 10 to 15 kt. Gusts up to 20 kt after midnight. Seas 3 to 4 ft. Wave Detail: SW 3 ft at 6 seconds and SE 2 ft at 9 seconds. Patchy fog. Vsby 1 NM or less.

TUE
SW winds 15 to 20 kt with gusts up to 25 kt. Seas 4 to 6 ft. Wave Detail: SW 5 ft at 6 seconds and SE 2 ft at 9 seconds. Patchy fog. Vsby 1 NM or less, increasing to 1 to 3 NM in the afternoon.

TUE NIGHT
SW winds 20 to 25 kt with gusts up to 30 kt. Seas 5 to 7 ft. Wave Detail: SW 7 ft at 7 seconds and SE 2 ft at 9 seconds. Patchy fog in the evening with vsby 1 to 3 NM.

WED
SW winds around 20 kt with gusts up to 25 kt. Seas 6 to 7 ft. Wave Detail: SW 6 ft at 7 seconds and SE 2 ft at 9 seconds.

WED NIGHT
SW winds 15 to 20 kt, becoming W 10 to 15 kt after midnight. Gusts up to 25 kt. Seas 6 to 7 ft, subsiding to 4 to 6 ft after midnight. Wave Detail: SW 6 ft at 7 seconds and SE 2 ft at 9 seconds, becoming SW 5 ft at 7 seconds and N 2 ft at 2 seconds. A chance of showers in the evening, then showers likely after midnight.

THU
NE winds 10 to 15 kt. Seas 3 to 4 ft. Showers likely.

THU NIGHT AND FRI
NE winds around 5 kt, becoming E. Seas 2 to 4 ft.

FRI NIGHT
SE winds 5 to 10 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.

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ANZ283-182100
Ocean Waters from Montauk NY to Marthas Vineyard from 25 to 60 NM
404 AM EDT Mon May 18 2026

TODAY
SE winds 5 to 10 kt. Seas 3 to 4 ft. Wave Detail: SW 3 ft at 7 seconds and SE 2 ft at 8 seconds. Patchy fog this morning with vsby 1 NM or less.

TONIGHT
SW winds 10 to 15 kt with gusts up to 20 kt. Seas 3 to 4 ft. Wave Detail: SW 4 ft at 5 seconds and SE 2 ft at 9 seconds. Patchy fog. Vsby 1 NM or less.

TUE
SW winds 15 to 20 kt with gusts up to 25 kt. Seas 4 to 6 ft. Wave Detail: SW 5 ft at 6 seconds and SE 2 ft at 9 seconds. Patchy fog. Vsby 1 NM or less, increasing to 1 to 3 NM in the afternoon.

TUE NIGHT
SW winds 20 to 25 kt with gusts up to 30 kt. Seas 5 to 7 ft. Wave Detail: SW 7 ft at 6 seconds and SE 4 ft at 9 seconds. Patchy fog in the evening with vsby 1 to 3 NM.

WED
SW winds around 20 kt with gusts up to 25 kt. Seas 6 to 7 ft. Wave Detail: SW 6 ft at 6 seconds and SE 2 ft at 9 seconds.

WED NIGHT
SW winds 15 to 20 kt with gusts up to 25 kt, becoming NW 10 to 15 kt after midnight. Seas 5 to 7 ft, subsiding to 4 to 5 ft after midnight. Wave Detail: SW 6 ft at 7 seconds and SE 2 ft at 9 seconds, becoming SW 5 ft at 7 seconds and SE 2 ft at 9 seconds. A chance of showers.

THU
NE winds 10 to 15 kt. Seas 3 to 4 ft. A chance of showers.

THU NIGHT AND FRI
E winds 5 to 10 kt. Seas 2 to 3 ft.

FRI NIGHT
SE winds 10 to 15 kt. Seas 3 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.

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