034
FZUS51 KBOX 200205
CWFBOX

Coastal Waters Forecast for Massachusetts and Rhode Island
National Weather Service Boston/Norton MA
1005 PM EDT Sat Jul 19 2025

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

ANZ200-201500-
1005 PM EDT Sat Jul 19 2025

.Synopsis for Massachusetts and Rhode Island coastal waters...
A warm front lifts N across the waters late tonight into Sun
followed by a cold front passage late Sun into Sun night. High pres
will build into the region Mon and Tue, moving offshore Wed into
Thu. High pres continues to influence the waters into Fri.

$$

ANZ250-201500-
Coastal waters east of Ipswich Bay and the Stellwagen Bank
National Marine Sanctuary-
1005 PM EDT Sat Jul 19 2025

.OVERNIGHT...S winds around 15 kt with 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.
.SUN...S winds around 15 kt with gusts up to 20 kt. Seas 2 to
3 ft. Wave Detail: S 3 ft at 4 seconds and SE 1 foot at
9 seconds. A chance of showers. Vsby 1 to 3 NM in the morning.
.SUN NIGHT...SW winds 10 to 15 kt, becoming NW after midnight.
Gusts up to 20 kt. Seas 2 to 3 ft. Wave Detail: S 3 ft at
4 seconds and NW 2 ft at 3 seconds. Showers likely in the evening
with vsby 1 to 3 NM.
.MON...N winds 10 to 15 kt with gusts up to 25 kt. Seas 2 to
3 ft. Wave Detail: NW 3 ft at 4 seconds and N 2 ft at 5 seconds.
.MON NIGHT...N winds 10 to 15 kt with gusts up to 25 kt. Seas
2 to 3 ft. Wave Detail: N 3 ft at 5 seconds and SE 2 ft at
8 seconds.
.TUE AND TUE NIGHT...W winds 5 to 10 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
7 seconds.
.WED THROUGH THU NIGHT...SW winds 15 to 20 kt with gusts up to
30 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.

$$

ANZ251-201500-
Massachusetts Bay and Ipswich Bay-
1005 PM EDT Sat Jul 19 2025

.OVERNIGHT...S winds 10 to 15 kt with gusts up to 20 kt. Seas
around 2 ft. Wave Detail: S 2 ft at 4 seconds and E 1 foot at
9 seconds.
.SUN...S winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to
3 ft. Wave Detail: S 2 ft at 4 seconds and E 1 foot at 9 seconds.
A chance of showers. Vsby 1 to 3 NM in the morning.
.SUN NIGHT...W winds 10 to 15 kt, becoming NW after midnight.
Gusts up to 20 kt. Seas around 2 ft. Wave Detail: NW 2 ft at
3 seconds and SE 2 ft at 4 seconds. Showers likely with a chance
of tstms in the evening. Some tstms may produce damaging winds,
small hail, and heavy rainfall in the evening with vsby 1 to
3 NM.
.MON...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 1 foot at 5 seconds.
.MON NIGHT...N winds 10 to 15 kt with gusts up to 20 kt. Seas
around 2 ft. Wave Detail: N 2 ft at 4 seconds and S 1 foot at
6 seconds.
.TUE AND TUE NIGHT...SW winds 5 to 10 kt with gusts up to 20 kt.
Seas around 2 ft. Wave Detail: N 2 ft at 5 seconds and S 1 foot
at 6 seconds.
.WED THROUGH THU NIGHT...SW winds 15 to 20 kt with gusts up to
30 kt. Seas 2 to 3 ft.

Winds and seas higher in and near tstms.

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.

$$

ANZ231-201500-
Cape Cod Bay-
1005 PM EDT Sat Jul 19 2025

.OVERNIGHT...S winds around 10 kt. Seas around 2 ft. Wave Detail:
S 1 foot at 3 seconds and E 1 foot at 9 seconds.
.SUN...S 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
9 seconds. Showers. Vsby 1 to 3 NM in the morning.
.SUN NIGHT...SW winds 10 to 15 kt, becoming NW after midnight.
Gusts up to 20 kt. Seas around 2 ft. Wave Detail: NW 2 ft at
3 seconds and SW 2 ft at 4 seconds. Showers likely in the evening
with vsby 1 to 3 NM.
.MON...N winds 10 to 15 kt with gusts up to 25 kt. Seas 2 to
3 ft. Wave Detail: N 2 ft at 4 seconds and S 1 foot at 6 seconds.
.MON NIGHT AND TUE...NE 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 SE 1 foot at
7 seconds.
.TUE NIGHT...S winds 5 to 10 kt, becoming SW after midnight. Seas
1 foot or less. Wave Detail: N 1 foot at 4 seconds and N 1 foot
at 5 seconds.
.WED AND WED NIGHT...S winds 10 to 15 kt with gusts up to 25 kt.
Seas 2 to 3 ft.
.THU AND THU NIGHT...SW winds 15 to 20 kt with gusts up to 30 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.

$$

ANZ254-201500-
Coastal waters from Provincetown MA to Chatham MA to Nantucket MA
out 20 nm-
1005 PM EDT Sat Jul 19 2025

.OVERNIGHT...S winds 10 to 15 kt with gusts up to 20 kt. Seas
2 to 3 ft. Wave Detail: S 2 ft at 4 seconds and N 1 foot at
3 seconds.
.SUN...S winds 10 to 15 kt with gusts up to 25 kt. Seas 2 to
3 ft. Wave Detail: SW 3 ft at 4 seconds and SE 1 foot at
9 seconds. A chance of showers in the morning. Showers with a
chance of tstms in the afternoon. Some tstms may produce damaging
winds, small hail, and heavy rainfall in the afternoon. Vsby 1 to
3 NM.
.SUN NIGHT...SW winds 10 to 15 kt, becoming NW after midnight.
Gusts up to 20 kt. Seas 2 to 3 ft. Wave Detail: S 3 ft at
5 seconds and NW 2 ft at 3 seconds. A chance of showers in the
evening.
.MON...N winds 10 to 15 kt with gusts up to 25 kt. Seas 2 to
3 ft. Wave Detail: N 3 ft at 4 seconds and S 2 ft at 6 seconds.
.MON NIGHT AND TUE...N winds 10 to 15 kt with gusts up to 20 kt.
Seas 2 to 3 ft. Wave Detail: NW 2 ft at 4 seconds and N 2 ft at
5 seconds.
.TUE NIGHT...SE winds around 5 kt, becoming W after midnight.
Seas 2 to 3 ft. Wave Detail: N 2 ft at 6 seconds and S 1 foot at
7 seconds.
.WED THROUGH THU NIGHT...SW winds 15 to 20 kt with gusts up to
30 kt. Seas 2 to 4 ft.

Winds and seas higher in and near tstms.

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.

$$

ANZ255-201500-
Coastal Waters extending out to 25 nm South of Marthas Vineyard
and Nantucket-
1005 PM EDT Sat Jul 19 2025

.OVERNIGHT...S winds 10 to 15 kt. Seas around 2 ft. Wave Detail:
S 2 ft at 5 seconds and SE 1 foot at 9 seconds.
.SUN...S winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to
3 ft. Wave Detail: S 3 ft at 4 seconds and SE 1 foot at
9 seconds. A chance of showers. Vsby 1 to 3 NM.
.SUN NIGHT...SW winds around 15 kt, becoming NW after midnight.
Gusts up to 20 kt. Seas 2 to 3 ft. Wave Detail: SW 3 ft at
5 seconds and SE 1 foot at 9 seconds. A chance of showers.
.MON...N winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to
3 ft. Wave Detail: S 3 ft at 6 seconds and N 2 ft at 4 seconds.
.MON NIGHT AND TUE...NE 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
7 seconds.
.TUE NIGHT...SE winds 5 to 10 kt, becoming W after midnight. Seas
2 to 3 ft. Wave Detail: S 2 ft at 7 seconds and NE 1 foot at
4 seconds.
.WED THROUGH THU...SW winds 15 to 20 kt with gusts up to 30 kt.
Seas 2 to 4 ft.
.THU NIGHT...SW winds around 20 kt with gusts up to 30 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.

$$

ANZ256-201500-
Coastal Waters from Montauk NY to Marthas Vineyard extending out
to 20 nm South of Block Island-
1005 PM EDT Sat Jul 19 2025

.OVERNIGHT...S winds 10 to 15 kt. Seas 2 to 3 ft. Wave Detail: S
2 ft at 4 seconds and SE 1 foot at 9 seconds. A slight chance of
showers.
.SUN...S winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to
3 ft. Wave Detail: S 3 ft at 5 seconds and SE 1 foot at
9 seconds. A chance of showers. Vsby 1 to 3 NM.
.SUN NIGHT...SW winds around 15 kt, becoming NW after midnight.
Gusts up to 20 kt. Seas 2 to 3 ft. Wave Detail: S 3 ft at
5 seconds and NW 2 ft at 3 seconds. A chance of showers.
.MON...NW winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to
3 ft. Wave Detail: S 3 ft at 6 seconds and N 2 ft at 4 seconds.
.MON NIGHT...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 2 ft at
7 seconds.
.TUE AND TUE NIGHT...SW 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
7 seconds.
.WED AND WED NIGHT...S winds 10 to 15 kt with gusts up to 20 kt.
Seas 2 to 3 ft.
.THU AND THU NIGHT...SW winds 15 to 20 kt with gusts up to 30 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.

$$

ANZ232-201500-
Nantucket Sound-
1005 PM EDT Sat Jul 19 2025

.OVERNIGHT...S winds 10 to 15 kt. Seas around 2 ft. Wave Detail:
S 2 ft at 3 seconds and N 1 foot at 4 seconds.
.SUN...S winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to
3 ft. Wave Detail: SW 3 ft at 4 seconds and SE 1 foot at
9 seconds. Showers in the morning. A chance of showers in the
afternoon. Vsby 1 to 3 NM.
.SUN NIGHT...SW winds 10 to 15 kt with gusts up to 20 kt,
becoming NW after midnight. Seas 2 to 3 ft. Wave Detail: W 3 ft
at 4 seconds and SE 1 foot at 9 seconds. A chance of showers.
.MON...N winds 10 to 15 kt with gusts up to 25 kt. Seas 2 to
3 ft. Wave Detail: N 2 ft at 3 seconds and S 1 foot at 6 seconds.
.MON NIGHT AND TUE...NE winds 10 to 15 kt with gusts up to 20 kt.
Seas around 2 ft. Wave Detail: NE 1 foot at 3 seconds and NW
1 foot at 4 seconds.
.TUE NIGHT...S winds 5 to 10 kt, becoming W after midnight. Seas
around 2 ft. Wave Detail: N 1 foot at 4 seconds and E 1 foot at
4 seconds.
.WED THROUGH THU NIGHT...SW winds 15 to 20 kt with gusts up to
30 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.

$$

ANZ233-201500-
Vineyard Sound-
1005 PM EDT Sat Jul 19 2025

.OVERNIGHT...S winds 10 to 15 kt. Seas around 2 ft. Wave Detail:
S 2 ft at 4 seconds and SE 1 foot at 9 seconds.
.SUN...S winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to
3 ft. Wave Detail: S 2 ft at 4 seconds and SE 1 foot at
9 seconds. Showers likely with a chance of tstms in the morning,
then showers likely in the afternoon. Some tstms may produce
heavy rainfall in the morning with vsby 1 to 3 NM.
.SUN NIGHT...SW 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 foot at 9 seconds. A chance of
showers.
.MON...N winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to
3 ft. Wave Detail: S 2 ft at 5 seconds and N 1 foot at 3 seconds.
.MON NIGHT...NE winds around 10 kt. Seas around 2 ft. Wave
Detail: N 1 foot at 3 seconds and S 1 foot at 6 seconds.
.TUE AND TUE NIGHT...SW winds 5 to 10 kt. Seas around 2 ft. Wave
Detail: N 1 foot at 3 seconds and S 1 foot at 7 seconds.
.WED THROUGH THU NIGHT...SW winds 15 to 20 kt with gusts up to
30 kt. Seas 2 to 4 ft.

Winds and seas higher in and near tstms.

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.

$$

ANZ234-201500-
Buzzards Bay-
1005 PM EDT Sat Jul 19 2025

.OVERNIGHT...S winds 10 to 15 kt. Seas around 2 ft. Wave Detail:
SW 2 ft at 3 seconds and SE 1 foot at 9 seconds.
.SUN...S winds 10 to 15 kt with gusts up to 25 kt. Seas 2 to
3 ft. Wave Detail: S 2 ft at 3 seconds and SE 1 foot at
9 seconds. Showers likely with a chance of tstms in the morning,
then showers likely in the afternoon. Some tstms may produce
heavy rainfall in the morning. Vsby 1 to 3 NM.
.SUN NIGHT...SW winds 10 to 15 kt with gusts up to 20 kt,
becoming NW after midnight. Seas 2 to 3 ft. Wave Detail: SW 2 ft
at 4 seconds and SE 1 foot at 9 seconds. A chance of showers.
.MON...N winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to
3 ft. Wave Detail: N 1 foot at 3 seconds and SW 1 foot at
5 seconds.
.MON NIGHT...NE winds 5 to 10 kt. Seas around 2 ft. Wave Detail:
NE 1 foot at 3 seconds and NW 1 foot at 3 seconds.
.TUE AND TUE NIGHT...SW winds 5 to 10 kt. Seas around 2 ft. Wave
Detail: N 1 foot at 3 seconds and S 1 foot at 6 seconds.
.WED AND WED NIGHT...SW winds 10 to 15 kt with gusts up to 25 kt.
Seas 2 to 3 ft.
.THU AND THU NIGHT...SW winds 15 to 20 kt with gusts up to 30 kt.
Seas 3 to 5 ft.

Winds and seas higher in and near tstms.

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.

$$

ANZ235-201500-
Rhode Island Sound-
1005 PM EDT Sat Jul 19 2025

.OVERNIGHT...S winds 10 to 15 kt. Seas around 2 ft. Wave Detail:
S 2 ft at 4 seconds and SE 1 foot at 8 seconds. A slight chance
of showers.
.SUN...S winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to
3 ft. Wave Detail: S 3 ft at 5 seconds and SE 1 foot at
8 seconds. Showers likely with a chance of tstms in the morning,
then showers likely in the afternoon. Some tstms may produce
heavy rainfall in the morning with vsby 1 to 3 NM.
.SUN NIGHT...SW winds 10 to 15 kt with gusts up to 20 kt,
becoming NW after midnight. Seas 2 to 3 ft. Wave Detail: S 3 ft
at 5 seconds and NW 2 ft at 3 seconds. A chance of showers.
.MON...NW 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 2 ft at 6 seconds.
.MON NIGHT...NE winds 10 to 15 kt. Gusts up to 20 kt after
midnight. Seas around 2 ft. Wave Detail: N 2 ft at 3 seconds and
S 2 ft at 7 seconds.
.TUE AND TUE NIGHT...SW winds 10 to 15 kt. Seas around 2 ft. Wave
Detail: N 2 ft at 3 seconds and S 2 ft at 7 seconds.
.WED THROUGH THU...SW winds 15 to 20 kt with gusts up to 30 kt.
Seas 2 to 4 ft.
.THU NIGHT...SW winds around 20 kt with gusts up to 30 kt. Seas
3 to 5 ft.

Winds and seas higher in and near tstms.

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.

$$

ANZ237-201500-
Block Island Sound-
1005 PM EDT Sat Jul 19 2025

.OVERNIGHT...S winds around 10 kt. Seas around 2 ft. Wave Detail:
SW 2 ft at 4 seconds and SE 1 foot at 8 seconds. A slight chance
of showers.
.SUN...S winds 10 to 15 kt. Gusts up to 20 kt in the afternoon.
Seas around 2 ft. Wave Detail: SW 2 ft at 4 seconds and SE 1 foot
at 9 seconds. Showers likely, mainly in the morning with vsby
1 to 3 NM.
.SUN NIGHT...SW 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 foot at 9 seconds. A chance of showers
in the evening.
.MON...NW winds 10 to 15 kt with gusts up to 20 kt. Seas around
2 ft. Wave Detail: S 2 ft at 6 seconds and N 1 foot at 3 seconds.
.MON NIGHT...NE winds 10 to 15 kt. Gusts up to 20 kt after
midnight. Seas around 2 ft. Wave Detail: NE 2 ft at 3 seconds and
SE 2 ft at 8 seconds.
.TUE AND TUE NIGHT...SW winds 5 to 10 kt with gusts up to 20 kt.
Seas around 2 ft. Wave Detail: NE 2 ft at 4 seconds and S 2 ft at
7 seconds.
.WED THROUGH THU NIGHT...SW winds 15 to 20 kt with gusts up to
30 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.

$$

ANZ230-201500-
Boston Harbor-
1005 PM EDT Sat Jul 19 2025

.OVERNIGHT...S winds 10 to 15 kt. Waves around 2 ft.
.SUN...S winds 10 to 15 kt with gusts up to 20 kt. Waves around
2 ft. A chance of showers. Vsby 1 to 3 NM in the morning.
.SUN NIGHT...W winds 10 to 15 kt with gusts up to 20 kt, becoming
NW after midnight. Waves around 2 ft. Showers likely with a
chance of tstms in the evening. Some tstms may produce damaging
winds, small hail, and heavy rainfall in the evening with vsby
1 to 3 NM.
.MON...N winds 10 to 15 kt with gusts up to 20 kt. Waves around
2 ft.
.MON NIGHT...N winds around 10 kt. Gusts up to 20 kt in the
evening. Waves around 2 ft.
.TUE AND TUE NIGHT...SW winds 5 to 10 kt. Waves around 2 ft.
.WED THROUGH THU NIGHT...SW winds 15 to 20 kt with gusts up to
25 kt. Waves 2 to 3 ft.

Winds and waves higher in and near tstms.

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.

$$

ANZ236-201500-
Narragansett Bay-
1005 PM EDT Sat Jul 19 2025

.OVERNIGHT...S winds around 10 kt. Waves around 2 ft.
.SUN...S winds 10 to 15 kt. Gusts up to 20 kt in the afternoon.
Waves 2 to 3 ft. Showers likely with a chance of tstms in the
morning, then showers likely in the afternoon. Some tstms may
produce heavy rainfall in the morning with vsby 1 to 3 NM.
.SUN NIGHT...SW winds 10 to 15 kt with gusts up to 20 kt,
becoming NW after midnight. Waves around 2 ft. Showers likely,
mainly in the evening.
.MON...NW winds around 10 kt with gusts up to 20 kt. Waves around
2 ft.
.MON NIGHT...N winds 5 to 10 kt. Waves around 2 ft.
.TUE AND TUE NIGHT...SW winds 5 to 10 kt. Waves around 2 ft.
.WED THROUGH THU NIGHT...SW winds 15 to 20 kt with gusts up to
30 kt. Waves 2 to 3 ft.

Winds and waves higher in and near tstms.

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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