860
FZUS51 KBOX 171404
CWFBOX

Coastal Waters Forecast for Massachusetts and Rhode Island
National Weather Service Boston/Norton MA
1004 AM EDT Sat May 17 2025

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

ANZ200-180300-
1004 AM EDT Sat May 17 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.

$$

ANZ250-180300-
Coastal waters east of Ipswich Bay and the Stellwagen Bank
National Marine Sanctuary-
1004 AM EDT Sat May 17 2025

.THIS AFTERNOON...SE winds 10 to 15 kt. Gusts up to 20 kt. Seas
2 to 4 ft. Wave Detail: SE 3 ft at 7 seconds and SE 2 ft at
4 seconds. Patchy fog. Vsby 1 NM or less.
.TONIGHT...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. Patchy fog. Vsby 1 NM or less.
.SUN...W winds 10 to 15 kt. Seas 2 to 3 ft. Wave Detail: W 2 ft
at 3 seconds and SE 2 ft at 7 seconds. Patchy fog in the morning
with vsby 1 to 3 NM.
.SUN NIGHT...W winds 10 to 15 kt with gusts up to 25 kt. Seas
2 to 4 ft. Wave Detail: W 3 ft at 4 seconds and SE 2 ft at
8 seconds.
.MON AND MON NIGHT...NW winds 15 to 20 kt with gusts up to 25 kt.
Seas 3 to 4 ft. Wave Detail: NW 3 ft at 4 seconds and NE 2 ft at
7 seconds.
.TUE THROUGH WED...NE winds 10 to 15 kt with gusts up to 20 kt.
Seas 3 to 5 ft. Wave Detail: NW 3 ft at 4 seconds and NE 3 ft at
7 seconds.
.WED NIGHT...E winds 15 to 20 kt. Seas 5 to 7 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.

$$

ANZ251-180300-
Massachusetts Bay and Ipswich Bay-
1004 AM EDT Sat May 17 2025

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

$$

ANZ231-180300-
Cape Cod Bay-
1004 AM EDT Sat May 17 2025

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

$$

ANZ254-180300-
Coastal waters from Provincetown MA to Chatham MA to Nantucket MA
out 20 nm-
1004 AM EDT Sat May 17 2025

...SMALL CRAFT ADVISORY IN EFFECT FROM SUNDAY MORNING THROUGH
MONDAY MORNING...

.THIS AFTERNOON...S winds 10 to 15 kt. Gusts up to 20 kt. Seas
2 to 4 ft. Wave Detail: SE 3 ft at 7 seconds and SE 1 foot at
3 seconds. Patchy fog. Vsby 1 NM or less.
.TONIGHT...SW winds 10 to 15 kt. Gusts up to 20 kt in the
evening. Seas 3 to 4 ft. Wave Detail: S 3 ft at 7 seconds and SE
1 foot at 4 seconds. Patchy fog. Vsby 1 NM or less.
.SUN...SW winds 10 to 15 kt with gusts up to 25 kt. Seas 3 to
5 ft. Wave Detail: S 4 ft at 7 seconds and W 2 ft at 4 seconds.
Patchy fog in the morning with vsby 1 NM or less.
.SUN NIGHT...W winds 10 to 15 kt with gusts up to 20 kt. Seas
3 to 5 ft. Wave Detail: S 4 ft at 8 seconds and W 2 ft at
4 seconds.
.MON AND MON NIGHT...NW winds 10 to 15 kt with gusts up to 25 kt.
Seas 3 to 5 ft. Wave Detail: N 3 ft at 5 seconds and S 3 ft at
8 seconds.
.TUE THROUGH WED...NE winds 10 to 15 kt with gusts up to 20 kt.
Seas 3 to 5 ft. Wave Detail: N 4 ft at 6 seconds and S 1 foot at
8 seconds.
.WED NIGHT...E winds 15 to 20 kt. Seas 5 to 7 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.

$$

ANZ255-180300-
Coastal Waters extending out to 25 nm South of Marthas Vineyard
and Nantucket-
1004 AM EDT Sat May 17 2025

...SMALL CRAFT ADVISORY IN EFFECT FROM SUNDAY MORNING THROUGH
MONDAY MORNING...

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

$$

ANZ256-180300-
Coastal Waters from Montauk NY to Marthas Vineyard extending out
to 20 nm South of Block Island-
1004 AM EDT Sat May 17 2025

...SMALL CRAFT ADVISORY IN EFFECT FROM SUNDAY MORNING THROUGH
MONDAY MORNING...

.THIS AFTERNOON...S winds 10 to 15 kt. Gusts up to 20 kt. Seas
3 to 4 ft. Wave Detail: SE 3 ft at 7 seconds. Patchy fog. Vsby
1 NM or less.
.TONIGHT...SW winds 10 to 15 kt, becoming W after midnight. Gusts
up to 20 kt. Seas 3 to 4 ft. Wave Detail: S 4 ft at 7 seconds.
Patchy fog. Vsby 1 NM or less, increasing to 1 to 3 NM after
midnight.
.SUN...W 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
5 ft at 7 seconds and W 1 foot at 4 seconds.
.SUN NIGHT...W winds 15 to 20 kt with gusts up to 25 kt. Seas
4 to 5 ft. Wave Detail: SW 5 ft at 8 seconds and NW 3 ft at
4 seconds.
.MON AND MON NIGHT...NW 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 SW 4 ft at
8 seconds.
.TUE AND TUE NIGHT...N winds 10 to 15 kt with gusts up to 20 kt,
becoming NE. Seas 2 to 3 ft. Wave Detail: N 3 ft at 5 seconds and
S 1 foot at 8 seconds.
.WED...E winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to
4 ft. A chance of showers.
.WED NIGHT...E winds 15 to 20 kt with gusts up to 25 kt. Seas
5 to 7 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.

$$

ANZ232-180300-
Nantucket Sound-
1004 AM EDT Sat May 17 2025

...SMALL CRAFT ADVISORY IN EFFECT FROM SUNDAY MORNING THROUGH
MONDAY MORNING...

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

$$

ANZ233-180300-
Vineyard Sound-
1004 AM EDT Sat May 17 2025

...SMALL CRAFT ADVISORY IN EFFECT FROM SUNDAY MORNING THROUGH
MONDAY MORNING...

.THIS AFTERNOON...S winds 10 to 15 kt. Seas around 2 ft. Wave
Detail: S 2 ft at 7 seconds and SE 1 foot at 3 seconds. Patchy
fog. Vsby 1 NM or less.
.TONIGHT...SW winds around 10 kt with gusts up to 20 kt, becoming
W after midnight. Seas around 2 ft. Wave Detail: S 2 ft at
7 seconds and S 1 foot at 4 seconds. Patchy fog. Vsby 1 NM or
less, increasing to 1 to 3 NM after midnight.
.SUN...W winds 10 to 15 kt, becoming SW 15 to 20 kt in the
afternoon. Gusts up to 25 kt. Seas 2 to 4 ft. Wave Detail: S 3 ft
at 7 seconds and SW 2 ft at 4 seconds.
.SUN NIGHT...W winds 10 to 15 kt, increasing to 15 to 20 kt after
midnight. Seas 2 to 3 ft. Wave Detail: SW 3 ft at 7 seconds and W
2 ft at 4 seconds.
.MON AND MON NIGHT...NW winds 15 to 20 kt. Seas 2 to 3 ft. Wave
Detail: SW 3 ft at 7 seconds and NW 2 ft at 4 seconds.
.TUE THROUGH WED...NE winds 10 to 15 kt with gusts up to 20 kt.
Seas around 2 ft. Wave Detail: E 2 ft at 3 seconds and NW 2 ft at
4 seconds.
.WED NIGHT...E winds 15 to 20 kt with gusts up to 25 kt. Seas
3 to 5 ft. Showers likely.

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.

$$

ANZ234-180300-
Buzzards Bay-
1004 AM EDT Sat May 17 2025

...SMALL CRAFT ADVISORY IN EFFECT FROM SUNDAY MORNING THROUGH
MONDAY MORNING...

.THIS AFTERNOON...S winds 10 to 15 kt. Seas 1 foot or less, then
around 2 ft. Wave Detail: SE 1 foot at 3 seconds and S 1 foot at
7 seconds, becoming S 2 ft at 7 seconds and SE 1 foot at
4 seconds. Patchy fog. Vsby 1 NM or less.
.TONIGHT...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. Patchy fog. Vsby
1 NM or less, increasing to 1 to 3 NM after midnight.
.SUN...W winds 10 to 15 kt, becoming SW 15 to 20 kt in the
afternoon. Gusts up to 25 kt. Seas 2 to 4 ft. Wave Detail: S 3 ft
at 5 seconds.
.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 W 2 ft at
4 seconds.
.MON AND MON NIGHT...NW winds 10 to 15 kt with gusts up to 20 kt.
Seas 2 to 3 ft. Wave Detail: NW 2 ft at 3 seconds and SW 2 ft at
7 seconds.
.TUE THROUGH WED...NE winds 10 to 15 kt with gusts up to 20 kt.
Seas around 2 ft. Wave Detail: N 2 ft at 3 seconds and S 1 foot
at 8 seconds.
.WED NIGHT...E winds 15 to 20 kt. Seas 3 to 5 ft. Showers likely.


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.

$$

ANZ235-180300-
Rhode Island Sound-
1004 AM EDT Sat May 17 2025

...SMALL CRAFT ADVISORY IN EFFECT FROM SUNDAY MORNING THROUGH
MONDAY MORNING...

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

$$

ANZ237-180300-
Block Island Sound-
1004 AM EDT Sat May 17 2025

...SMALL CRAFT ADVISORY IN EFFECT FROM SUNDAY MORNING THROUGH
MONDAY MORNING...

.THIS AFTERNOON...S winds 5 to 10 kt. Seas 2 to 3 ft. Wave
Detail: SE 3 ft at 7 seconds. Patchy fog. Vsby 1 NM or less.
.TONIGHT...SW winds 10 to 15 kt with gusts up to 20 kt, becoming
W after midnight. Seas 2 to 3 ft. Wave Detail: S 3 ft at
7 seconds and W 1 foot at 3 seconds. Patchy fog. Vsby 1 NM or
less, increasing to 1 to 3 NM after midnight.
.SUN...W 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: S 4 ft
at 7 seconds and W 2 ft at 4 seconds.
.SUN NIGHT...W winds 10 to 15 kt with gusts up to 25 kt. Seas
3 to 4 ft. Wave Detail: S 4 ft at 8 seconds and W 2 ft at
4 seconds.
.MON AND MON NIGHT...NW winds 10 to 15 kt with gusts up to 20 kt.
Seas 2 to 4 ft. Wave Detail: S 3 ft at 8 seconds and W 2 ft at
4 seconds.
.TUE AND TUE NIGHT...N winds 10 to 15 kt, becoming NE 5 to 10 kt.
Seas around 2 ft. Wave Detail: N 2 ft at 3 seconds and S 1 foot
at 8 seconds.
.WED...E winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to
3 ft. A chance of showers.
.WED NIGHT...E winds 15 to 20 kt. Seas 4 to 6 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.

$$

ANZ230-180300-
Boston Harbor-
1004 AM EDT Sat May 17 2025

.THIS AFTERNOON...SE winds around 10 kt. Waves 1 foot or less.
Patchy fog. A slight chance of showers. Vsby 1 to 3 NM.
.TONIGHT...S winds 5 to 10 kt, becoming W after midnight. Waves
1 foot or less.
.SUN...W winds 10 to 15 kt. Gusts up to 20 kt in the afternoon.
Waves around 2 ft. A chance of showers in the afternoon.
.SUN NIGHT...W winds 10 to 15 kt with gusts up to 20 kt. Waves
around 2 ft. A chance of showers in the evening.
.MON AND MON NIGHT...NW winds 15 to 20 kt with gusts up to 25 kt.
Waves around 2 ft.
.TUE THROUGH WED...NE winds 10 to 15 kt with gusts up to 20 kt.
Waves 2 to 3 ft.
.WED NIGHT...E winds 10 to 15 kt with gusts up to 20 kt. Waves
2 to 3 ft, except 4 to 6 ft at the outer harbor entrance. 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.

$$

ANZ236-180300-
Narragansett Bay-
1004 AM EDT Sat May 17 2025

.THIS AFTERNOON...S winds 5 to 10 kt. Waves 2 to 3 ft. Patchy
fog. Vsby 1 NM or less.
.TONIGHT...SW winds around 10 kt, becoming W after midnight.
Waves 2 to 3 ft. Patchy fog in the evening with vsby 1 NM or
less.
.SUN...W winds 10 to 15 kt with gusts up to 20 kt. Waves 2 to
4 ft.
.SUN NIGHT...W winds 10 to 15 kt with gusts up to 20 kt. Waves
2 to 4 ft.
.MON AND MON NIGHT...NW winds 10 to 15 kt with gusts up to 20 kt.
Waves 2 to 3 ft.
.TUE AND TUE NIGHT...N winds 5 to 10 kt. Waves around 2 ft.
.WED...NE winds 10 to 15 kt with gusts up to 20 kt. Waves 2 to
3 ft. A chance of showers.
.WED NIGHT...E winds 10 to 15 kt with gusts up to 20 kt. Waves
2 to 3 ft, except 4 to 6 ft at the bay entrance. Showers likely.

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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