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000
FZUS51 KBOX 212020
CWFBOX

Coastal Waters Forecast for Massachusetts and Rhode Island
National Weather Service Boston/Norton MA
419 PM EDT Sun Apr 21 2024

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

ANZ200-220900-
419 PM EDT Sun Apr 21 2024

.Synopsis for Massachusetts and Rhode Island coastal waters...
High pres generally dominates weather conditions through Tue.
Northwest breezes around 20 to 25 kt are possible Mon, decreasing
winds expected Tue. A cold front will cross the region Wed into Wed
night with a round of showers. Gusty northwest winds return behind
this front for Thurs, with high pres ridging in for Fri and Sat.

$$

ANZ250-220900-
Coastal waters east of Ipswich Bay and the Stellwagen Bank
National Marine Sanctuary-
419 PM EDT Sun Apr 21 2024

.TONIGHT...W 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 2 ft at 7 seconds.
.MON...NW winds 10 to 15 kt with gusts up to 20 kt, diminishing
to 5 to 10 kt in the afternoon. Seas 2 to 4 ft. Wave Detail: NW
3 ft at 4 seconds and SE 2 ft at 7 seconds.
.MON NIGHT...S winds around 5 kt, increasing to 5 to 10 kt after
midnight. Seas around 2 ft. Wave Detail: NW 1 ft at 4 seconds and
SE 1 ft at 7 seconds.
.TUE...S winds 5 to 10 kt, increasing to 10 to 15 kt with gusts
up to 25 kt in the afternoon. Seas 2 to 4 ft. Wave Detail: S 3 ft
at 3 seconds and SE 2 ft at 10 seconds.
.TUE NIGHT...S winds 15 to 20 kt, diminishing to 10 to 15 kt
after midnight. Gusts up to 25 kt. Seas 2 to 4 ft. Wave Detail: S
4 ft at 4 seconds and E 1 ft at 10 seconds.
.WED...S winds 10 to 15 kt with gusts up to 25 kt. Seas 3 to
5 ft. Wave Detail: S 3 ft at 4 seconds and SE 2 ft at 10 seconds.
A chance of showers.
.WED NIGHT...NW winds 20 to 25 kt with gusts up to 30 kt. Seas
5 to 7 ft. A chance of showers in the evening.
.THU...NW winds 15 to 20 kt with gusts up to 30 kt. Seas 4 to
6 ft.
.THU NIGHT AND FRI...W winds 10 to 15 kt. Gusts up to 20 kt. Seas
2 to 4 ft.
.FRI NIGHT...SW 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.

$$

ANZ251-220900-
Massachusetts Bay and Ipswich Bay-
419 PM EDT Sun Apr 21 2024

.TONIGHT...W winds 10 to 15 kt. Gusts up to 20 kt after midnight.
Seas around 2 ft. Wave Detail: W 2 ft at 3 seconds and SE 1 ft at
7 seconds.
.MON...NW winds 10 to 15 kt with gusts up to 20 kt, becoming N
5 to 10 kt in the afternoon. Seas around 2 ft. Wave Detail: NW
2 ft at 3 seconds and SE 1 ft at 7 seconds.
.MON NIGHT...S winds around 5 kt. Seas around 2 ft in the
evening, then 1 foot or less. Wave Detail: NW 1 ft at 3 seconds
and SE 1 ft at 6 seconds, becoming SW 1 ft at 2 seconds and SE
1 ft at 4 seconds.
.TUE...S winds 5 to 10 kt, increasing to 15 to 20 kt with gusts
up to 25 kt in the afternoon. Seas 2 to 3 ft. Wave Detail: S 3 ft
at 3 seconds and E 1 ft at 10 seconds.
.TUE NIGHT...S winds 15 to 20 kt with gusts up to 25 kt. Seas
2 to 3 ft. Wave Detail: S 3 ft at 4 seconds and E 1 ft at
10 seconds.
.WED...SW winds around 15 kt with gusts up to 25 kt. Seas 2 to
4 ft. Wave Detail: S 3 ft at 4 seconds and E 1 ft at 4 seconds. A
chance of showers.
.WED NIGHT...NW winds 20 to 25 kt, diminishing to 15 to 20 kt
after midnight. Gusts up to 30 kt. Seas 3 to 5 ft. A chance of
showers in the evening.
.THU AND THU NIGHT...NW winds 15 to 20 kt with gusts up to 30 kt,
diminishing to 10 to 15 kt with gusts up to 20 kt. Seas 2 to
4 ft.
.FRI AND FRI NIGHT...NW winds around 10 kt, becoming SW. 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.

$$

ANZ231-220900-
Cape Cod Bay-
419 PM EDT Sun Apr 21 2024

.TONIGHT...W winds 5 to 10 kt. Gusts up to 20 kt after midnight.
Seas around 2 ft. Wave Detail: SW 1 ft at 3 seconds and SE 1 ft
at 7 seconds.
.MON...NW winds 10 to 15 kt with gusts up to 20 kt, becoming N
5 to 10 kt in the afternoon. Seas around 2 ft. Wave Detail: NW
2 ft at 3 seconds and SE 1 ft at 6 seconds.
.MON NIGHT...S winds around 5 kt. Seas 1 foot or less. Wave
Detail: NW 1 ft at 4 seconds and SE 1 ft at 6 seconds.
.TUE...S winds 5 to 10 kt. Seas 1 foot or less. Wave Detail: S
1 ft at 3 seconds and S 1 ft at 6 seconds.
.TUE NIGHT...S winds around 10 kt. Seas 1 foot or less. Wave
Detail: S 1 ft at 3 seconds and E 1 ft at 10 seconds.
.WED...SW winds 10 to 15 kt with gusts up to 25 kt. Seas 2 to
4 ft. Wave Detail: S 2 ft at 3 seconds and E 1 ft at 4 seconds. A
chance of showers.
.WED NIGHT...NW winds 15 to 20 kt with gusts up to 30 kt. Seas
3 to 5 ft. A chance of showers in the evening.
.THU...NW winds 15 to 20 kt with gusts up to 30 kt. Seas 2 to
4 ft.
.THU NIGHT THROUGH FRI NIGHT...SW 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.

$$

ANZ254-220900-
Coastal waters from Provincetown MA to Chatham MA to Nantucket MA
out 20 nm-
419 PM EDT Sun Apr 21 2024

.TONIGHT...SW winds around 10 kt, becoming NW with gusts up to
20 kt after midnight. Seas 2 to 3 ft. Wave Detail: W 2 ft at
4 seconds and SE 2 ft at 7 seconds.
.MON...NW winds 10 to 15 kt. Gusts up to 20 kt in the morning.
Seas 2 to 4 ft. Wave Detail: NW 2 ft at 4 seconds and SE 2 ft at
6 seconds.
.MON NIGHT...S winds around 5 kt. Seas 2 to 3 ft. Wave Detail: NW
2 ft at 4 seconds and SE 2 ft at 11 seconds.
.TUE...SE winds 5 to 10 kt. Seas around 2 ft. Wave Detail: S 2 ft
at 8 seconds and SE 2 ft at 11 seconds.
.TUE NIGHT...S winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: SE
2 ft at 5 seconds and NE 1 ft at 4 seconds.
.WED...S winds 10 to 15 kt, becoming SW 15 to 20 kt in the
afternoon. Gusts up to 25 kt. Seas 2 to 4 ft, building to 4 to
5 ft in the afternoon. Wave Detail: S 2 ft at 5 seconds and SE
2 ft at 9 seconds, becoming S 3 ft at 4 seconds and SE 3 ft at
10 seconds.
.WED NIGHT...NW winds 15 to 20 kt with gusts up to 30 kt. Seas
5 to 7 ft.
.THU...NW winds 15 to 20 kt with gusts up to 30 kt. Seas 5 to
7 ft.
.THU NIGHT...W winds 10 to 15 kt with gusts up to 20 kt. Seas
3 to 5 ft.
.FRI AND FRI NIGHT...NW winds around 10 kt, becoming SW. 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.

$$

ANZ255-220900-
Coastal Waters extending out to 25 nm South of Marthas Vineyard
and Nantucket-
419 PM EDT Sun Apr 21 2024

.TONIGHT...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 4 seconds and
SE 2 ft at 7 seconds.
.MON...NW winds 10 to 15 kt with gusts up to 20 kt, diminishing
to 5 to 10 kt in the afternoon. Seas 2 to 3 ft. Wave Detail: NW
2 ft at 4 seconds and SE 1 ft at 6 seconds.
.MON NIGHT...S winds around 5 kt. Seas around 2 ft. Wave Detail:
SE 2 ft at 9 seconds and W 1 ft at 4 seconds.
.TUE...SE winds 5 to 10 kt. Seas around 2 ft. Wave Detail: S 2 ft
at 4 seconds and SE 2 ft at 9 seconds.
.TUE NIGHT...SE winds 5 to 10 kt, becoming S 10 to 15 kt after
midnight. Seas 2 to 3 ft. Wave Detail: SE 3 ft at 5 seconds and
NE 1 ft at 4 seconds.
.WED...S winds 15 to 20 kt with gusts up to 30 kt. Seas 3 to
5 ft. Wave Detail: SW 4 ft at 6 seconds and SE 3 ft at 9 seconds.
.WED NIGHT...NW winds 15 to 20 kt with gusts up to 30 kt. Seas
4 to 6 ft.
.THU...NW winds 15 to 20 kt with gusts up to 25 kt. Seas 4 to
6 ft.
.THU NIGHT AND FRI...W winds 10 to 15 kt. Gusts up to 20 kt. Seas
2 to 4 ft.
.FRI NIGHT...SW winds 10 to 15 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.

$$

ANZ256-220900-
Coastal Waters from Montauk NY to Marthas Vineyard extending out
to 20 nm South of Block Island-
419 PM EDT Sun Apr 21 2024

.TONIGHT...W winds 10 to 15 kt, becoming NW after midnight. Gusts
up to 20 kt. Seas 2 to 3 ft. Wave Detail: SW 2 ft at 4 seconds
and SE 2 ft at 7 seconds.
.MON...NW winds 10 to 15 kt with gusts up to 20 kt, becoming W
5 to 10 kt in the afternoon. Seas 2 to 3 ft. Wave Detail: NW 2 ft
at 4 seconds and SE 1 ft at 7 seconds.
.MON NIGHT...S winds 5 to 10 kt. Seas around 2 ft. Wave Detail:
SE 2 ft at 9 seconds and SW 1 ft at 4 seconds.
.TUE...S winds 5 to 10 kt. Seas around 2 ft. Wave Detail: S 2 ft
at 8 seconds and SE 2 ft at 9 seconds.
.TUE NIGHT...S winds 10 to 15 kt. Gusts up to 20 kt after
midnight. Seas 2 to 3 ft. Wave Detail: S 3 ft at 5 seconds and SE
1 ft at 10 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 6 seconds and SE 2 ft at 9 seconds.
A chance of showers.
.WED NIGHT...NW winds 15 to 20 kt with gusts up to 30 kt. Seas
4 to 6 ft. A chance of showers in the evening.
.THU...NW winds around 15 kt with gusts up to 25 kt. Seas 3 to
5 ft.
.THU NIGHT AND FRI...W winds 10 to 15 kt. Gusts up to 20 kt. Seas
2 to 4 ft.
.FRI NIGHT...SW winds 10 to 15 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.

$$

ANZ232-220900-
Nantucket Sound-
419 PM EDT Sun Apr 21 2024

.TONIGHT...W winds 10 to 15 kt, becoming NW after midnight. Gusts
up to 20 kt. Seas around 2 ft. Wave Detail: W 2 ft at 3 seconds
and SE 1 ft at 6 seconds.
.MON...NW winds 10 to 15 kt with gusts up to 20 kt, becoming N
5 to 10 kt in the afternoon. Seas around 2 ft. Wave Detail: NW
2 ft at 3 seconds and SE 1 ft at 6 seconds.
.MON NIGHT...S winds around 5 kt. Seas 1 foot or less. Wave
Detail: SW 1 ft at 3 seconds and SE 1 ft at 7 seconds.
.TUE...S winds 5 to 10 kt. Seas 1 foot or less. Wave Detail: S
1 ft at 3 seconds and E 1 ft at 10 seconds.
.TUE NIGHT...S winds 5 to 10 kt. Seas 1 foot or less. Wave
Detail: S 1 ft at 3 seconds and E 1 ft at 10 seconds.
.WED...S winds 10 to 15 kt, becoming SW 15 to 20 kt in the
afternoon. Gusts up to 25 kt. Seas 2 to 3 ft. Wave Detail: S 2 ft
at 4 seconds and E 1 ft at 4 seconds. A chance of showers.
.WED NIGHT...NW winds 15 to 20 kt with gusts up to 30 kt. Seas
2 to 3 ft.
.THU THROUGH FRI NIGHT...SW winds 10 to 15 kt with gusts up to
25 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.

$$

ANZ233-220900-
Vineyard Sound-
419 PM EDT Sun Apr 21 2024

.TONIGHT...W winds 10 to 15 kt, becoming NW after midnight. Gusts
up to 20 kt. Seas around 2 ft. Wave Detail: SW 2 ft at 4 seconds
and SE 1 ft at 7 seconds.
.MON...NW winds around 10 kt with gusts up to 20 kt, becoming W
in the afternoon. Seas around 2 ft in the morning, then 1 foot or
less. Wave Detail: W 1 ft at 4 seconds and SE 1 ft at 7 seconds.
.MON NIGHT...S winds 5 to 10 kt. Seas around 2 ft. Wave Detail:
SW 1 ft at 4 seconds and SE 1 ft at 7 seconds.
.TUE...S winds 5 to 10 kt, increasing to 10 to 15 kt in the
afternoon. Seas 1 foot or less. Wave Detail: S 1 ft at 4 seconds
and SE 1 ft at 9 seconds.
.TUE NIGHT...S winds 10 to 15 kt. Seas 1 foot or less, then
around 2 ft after midnight. Wave Detail: S 1 ft at 4 seconds and
SE 1 ft at 9 seconds, becoming S 2 ft at 4 seconds and SE 1 ft at
10 seconds.
.WED AND WED NIGHT...NW winds 15 to 20 kt with gusts up to 25 kt.
Seas 2 to 4 ft. Wave Detail: SW 3 ft at 5 seconds and SE 1 ft at
9 seconds. A chance of showers.
.THU THROUGH FRI NIGHT...SW winds 10 to 15 kt with gusts up to
25 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.

$$

ANZ234-220900-
Buzzards Bay-
419 PM EDT Sun Apr 21 2024

.TONIGHT...W winds 10 to 15 kt with gusts up to 20 kt, becoming
NW after midnight. Seas around 2 ft. Wave Detail: SW 2 ft at
4 seconds and SE 1 ft at 7 seconds.
.MON...NW winds around 10 kt, becoming SW in the afternoon. Seas
1 foot or less. Wave Detail: NW 1 ft at 3 seconds and SE 1 ft at
7 seconds.
.MON NIGHT...S winds 5 to 10 kt. Seas 1 foot or less. Wave
Detail: SW 1 ft at 4 seconds and SE 1 ft at 7 seconds.
.TUE...S winds 5 to 10 kt, increasing to 10 to 15 kt in the
afternoon. Seas 1 foot or less. Wave Detail: SW 1 ft at 3 seconds
and S 1 ft at 7 seconds.
.TUE NIGHT...S winds 10 to 15 kt. Seas 1 foot or less. Wave
Detail: S 1 ft at 4 seconds and SE 1 ft at 10 seconds.
.WED AND WED NIGHT...NW winds 15 to 20 kt with gusts up to 25 kt.
Seas 2 to 4 ft. Wave Detail: SW 3 ft at 5 seconds and E 1 ft at
4 seconds. A chance of showers.
.THU THROUGH FRI NIGHT...SW winds 10 to 15 kt with gusts up to
25 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.

$$

ANZ235-220900-
Rhode Island Sound-
419 PM EDT Sun Apr 21 2024

.TONIGHT...W winds 10 to 15 kt, becoming NW after midnight. Gusts
up to 20 kt. Seas 2 to 3 ft. Wave Detail: SW 2 ft at 4 seconds
and SE 2 ft at 7 seconds.
.MON...NW winds 10 to 15 kt with gusts up to 20 kt, becoming SW
5 to 10 kt in the afternoon. Seas around 2 ft. Wave Detail: W
2 ft at 4 seconds and SE 1 ft at 7 seconds.
.MON NIGHT...S winds 5 to 10 kt. Seas around 2 ft. Wave Detail: S
2 ft at 9 seconds and SW 1 ft at 4 seconds.
.TUE...S winds 5 to 10 kt, increasing to 10 to 15 kt in the
afternoon. Seas around 2 ft in the morning, then 1 foot or less.
Wave Detail: S 2 ft at 8 seconds and SW 1 ft at 3 seconds,
becoming S 1 ft at 4 seconds and SE 1 ft at 9 seconds.
.TUE NIGHT...S winds 10 to 15 kt. Seas around 2 ft. Wave Detail:
S 2 ft at 5 seconds and SE 1 ft at 9 seconds.
.WED AND WED NIGHT...NW winds 15 to 20 kt with gusts up to 25 kt.
Seas 2 to 4 ft. Wave Detail: SW 4 ft at 7 seconds and NW 3 ft at
4 seconds. A chance of showers.
.THU AND THU NIGHT...W winds 10 to 15 kt with gusts up to 25 kt.
Seas 2 to 4 ft.
.FRI AND FRI NIGHT...W winds around 10 kt, becoming SW. 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.

$$

ANZ237-220900-
Block Island Sound-
419 PM EDT Sun Apr 21 2024

.TONIGHT...W winds 5 to 10 kt, becoming NW after midnight. Seas
around 2 ft. Wave Detail: W 2 ft at 3 seconds and SE 2 ft at
7 seconds.
.MON...NW winds around 10 kt, becoming W in the afternoon. Seas
around 2 ft. Wave Detail: W 1 ft at 3 seconds and SE 1 ft at
7 seconds.
.MON NIGHT...SW winds 5 to 10 kt, becoming S after midnight. Seas
around 2 ft. Wave Detail: S 2 ft at 9 seconds and SW 1 ft at
3 seconds.
.TUE...S winds 5 to 10 kt. Seas around 2 ft in the morning, then
1 foot or less. Wave Detail: S 2 ft at 8 seconds and SW 1 ft at
3 seconds, becoming S 1 ft at 4 seconds and SE 1 ft at 9 seconds.
.TUE NIGHT...S winds around 10 kt. Seas around 2 ft. Wave Detail:
S 2 ft at 4 seconds and SE 1 ft at 9 seconds.
.WED AND WED NIGHT...NW 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 W 3 ft at
4 seconds. A chance of showers.
.THU THROUGH FRI NIGHT...SW winds 10 to 15 kt with gusts up to
25 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.

$$

ANZ230-220900-
Boston Harbor-
419 PM EDT Sun Apr 21 2024

.TONIGHT...W winds 10 to 15 kt. Waves 1 foot or less.
.MON...NW winds 10 to 15 kt, diminishing to 5 to 10 kt in the
afternoon. Waves 1 foot or less.
.MON NIGHT...S winds around 5 kt. Waves 1 foot or less.
.TUE...S winds 5 to 10 kt, increasing to 15 to 20 kt with gusts
up to 25 kt in the afternoon. Waves 1 foot or less, then around
2 ft in the afternoon.
.TUE NIGHT...S winds 15 to 20 kt with gusts up to 25 kt. Waves
around 2 ft.
.WED AND WED NIGHT...NW winds 20 to 25 kt. Waves around 2 ft. A
chance of showers.
.THU THROUGH FRI NIGHT...SW winds 10 to 15 kt with gusts up to
25 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.

$$

ANZ236-220900-
Narragansett Bay-
419 PM EDT Sun Apr 21 2024

.TONIGHT...W winds 5 to 10 kt. Waves around 2 ft.
.MON...NW winds 5 to 10 kt. Waves around 2 ft in the morning,
then 1 foot or less.
.MON NIGHT...SW winds 5 to 10 kt, becoming S after midnight.
Waves 1 foot or less.
.TUE...S 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.
.TUE NIGHT...S winds 10 to 15 kt. Gusts up to 20 kt in the
evening. Waves 1 foot or less, then around 2 ft after midnight.
.WED AND WED NIGHT...NW winds 10 to 15 kt with gusts up to 25 kt.
Waves 2 to 3 ft. A chance of showers.
.THU THROUGH FRI NIGHT...SW winds 10 to 15 kt with gusts up to
25 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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