FZUS51 KBOX 180604
CWFBOX
Coastal Waters Forecast for Massachusetts and Rhode Island
National Weather Service Boston/Norton MA
104 AM EST Thu Dec 18 2025
Coastal waters from the Merrimack River MA to Watch Hill RI out
to 25 NM
ANZ200-181900-
104 AM EST Thu Dec 18 2025
.Synopsis for Massachusetts and Rhode Island coastal waters...
A period of gale force SW gusts will develop ahead of a cold front
that moves past the waters overnight. High pres will then cross the
waters Thu. A strong cold front is expected to impact the waters Fri
afternoon and evening. It will be preceded by strong S gale force
gusts Fri, shifting to W gale force gusts Fri night. High pres
should build over the waters Sat afternoon before moving offshore,
then another cold front should move through on Sun.
$$
ANZ250-181900-
Coastal waters east of Ipswich Bay and the Stellwagen Bank
National Marine Sanctuary-
104 AM EST Thu Dec 18 2025
...GALE WARNING IN EFFECT FROM LATE TONIGHT THROUGH SATURDAY
MORNING...
.REST OF TONIGHT...NW winds 15 to 20 kt with gusts up to 25 kt.
Seas 2 to 4 ft. Wave Detail: NW 4 ft at 5 seconds and SE 1 foot
at 10 seconds.
.THU...SW winds 5 to 10 kt, becoming S 15 to 20 kt with gusts up
to 25 kt in the afternoon. Seas 2 to 4 ft. Wave Detail: S 3 ft at
4 seconds and SE 1 foot at 10 seconds.
.THU NIGHT...S winds 15 to 20 kt with gusts up to 25 kt,
increasing to 20 to 25 kt with gusts up to 35 kt after midnight.
Seas 3 to 5 ft, building to 5 to 7 ft after midnight. Wave
Detail: S 4 ft at 5 seconds and SE 1 foot at 10 seconds, becoming
S 6 ft at 6 seconds and SE 1 foot at 11 seconds. A chance of rain
after midnight with vsby 1 NM or less.
.FRI...S winds 25 to 35 kt, increasing to 30 to 40 kt in the
afternoon. Gusts up to 50 kt. Seas 6 to 9 ft, building to 8 to
11 ft in the afternoon. Wave Detail: SE 9 ft at 11 seconds and S
7 ft at 6 seconds, becoming SE 9 ft at 9 seconds and S 6 ft at
6 seconds. Rain. Vsby 1 NM or less.
.FRI NIGHT...W winds 25 to 30 kt with gusts up to 40 kt. Seas
8 to 11 ft. Wave Detail: W 9 ft at 6 seconds and SE 8 ft at
10 seconds. A chance of rain in the evening.
.SAT...W winds 25 to 30 kt with gusts up to 35 kt, diminishing to
around 15 kt with gusts up to 20 kt in the afternoon. Seas 6 to
9 ft, subsiding to 5 to 7 ft in the afternoon. Wave Detail: W
8 ft at 6 seconds and SE 5 ft at 11 seconds, becoming W 5 ft at
6 seconds and SE 4 ft at 11 seconds.
.SAT NIGHT...SW winds 15 to 20 kt, increasing to 20 to 25 kt
after midnight. Gusts up to 30 kt. Seas 4 to 6 ft.
.SUN...W winds 20 to 25 kt with gusts up to 30 kt. Seas 4 to
6 ft.
.SUN NIGHT AND MON...NW winds 25 to 30 kt with gusts up to 35 kt.
Seas 5 to 8 ft.
.MON NIGHT...NW winds 15 to 20 kt with gusts up to 25 kt. Seas
4 to 6 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.
$$
ANZ251-181900-
Massachusetts Bay and Ipswich Bay-
104 AM EST Thu Dec 18 2025
...GALE WARNING IN EFFECT FROM LATE TONIGHT THROUGH SATURDAY
MORNING...
.REST OF TONIGHT...NW winds 10 to 15 kt with gusts up to 20 kt.
Seas around 2 ft. Wave Detail: NW 2 ft at 4 seconds and SE 1 foot
at 10 seconds.
.THU...SW winds 5 to 10 kt, becoming S 15 to 20 kt in the
afternoon. Seas 2 to 3 ft. Wave Detail: S 2 ft at 3 seconds and E
1 foot at 10 seconds.
.THU NIGHT...S winds 15 to 20 kt, increasing to 20 to 25 kt after
midnight. Gusts up to 30 kt. Seas 2 to 3 ft, building to 3 to
5 ft after midnight. Wave Detail: SE 3 ft at 4 seconds and E
1 foot at 10 seconds, becoming SE 5 ft at 5 seconds and SE 1 foot
at 11 seconds. A chance of rain after midnight with vsby 1 NM or
less.
.FRI...S winds 25 to 35 kt with gusts up to 45 kt. Seas 5 to
7 ft. Wave Detail: SE 7 ft at 7 seconds. Rain. Vsby 1 NM or less.
.FRI NIGHT...W winds 25 to 30 kt with gusts up to 40 kt. Seas
4 to 6 ft. Wave Detail: W 5 ft at 5 seconds and SE 5 ft at
10 seconds. A chance of rain in the evening.
.SAT...W winds 20 to 25 kt with gusts up to 30 kt, diminishing to
10 to 15 kt with gusts up to 20 kt in the afternoon. Seas 4 to
6 ft, subsiding to 2 to 4 ft in the afternoon. Wave Detail: W
5 ft at 5 seconds and SE 3 ft at 11 seconds, becoming W 3 ft at
4 seconds and E 3 ft at 11 seconds.
.SAT NIGHT...SW winds 15 to 20 kt, increasing to 20 to 25 kt
after midnight. Gusts up to 30 kt. Seas 2 to 4 ft.
.SUN THROUGH MON...NW winds 25 to 30 kt. Seas 3 to 5 ft.
.MON NIGHT...NW winds 15 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.
$$
ANZ231-181900-
Cape Cod Bay-
104 AM EST Thu Dec 18 2025
...STORM WARNING IN EFFECT FROM FRIDAY MORNING THROUGH FRIDAY
AFTERNOON...
.REST OF TONIGHT...NW winds 10 to 15 kt with gusts up to 20 kt.
Seas around 2 ft. Wave Detail: NW 2 ft at 4 seconds and SE 1 foot
at 10 seconds.
.THU...SW winds 5 to 10 kt, becoming S 10 to 15 kt with gusts up
to 20 kt in the afternoon. Seas 1 foot or less, then around 2 ft
in the afternoon. Wave Detail: NW 1 foot at 4 seconds and SE
1 foot at 10 seconds, becoming S 2 ft at 3 seconds and SE 1 foot
at 8 seconds.
.THU NIGHT...S winds 15 to 20 kt, increasing to 20 to 25 kt after
midnight. Gusts up to 30 kt. Seas 2 to 3 ft. Wave Detail: S 3 ft
at 4 seconds and SE 1 foot at 7 seconds. A chance of rain after
midnight with vsby 1 to 3 NM.
.FRI...S winds 25 to 35 kt. Gusts up to 45 kt, increasing to
55 kt in the afternoon. Seas 4 to 6 ft. Wave Detail: SE 6 ft at
13 seconds and S 5 ft at 5 seconds. Rain. Vsby 1 NM or less.
.FRI NIGHT...W winds 25 to 30 kt with gusts up to 40 kt. Seas
4 to 6 ft. Wave Detail: W 5 ft at 5 seconds and S 4 ft at
10 seconds. A chance of rain in the evening.
.SAT...W winds 20 to 25 kt with gusts up to 30 kt, diminishing to
10 to 15 kt with gusts up to 20 kt in the afternoon. Seas 3 to
5 ft. Wave Detail: NW 5 ft at 6 seconds and SE 3 ft at
11 seconds.
.SAT NIGHT...SW winds 15 to 20 kt with gusts up to 30 kt. Seas
2 to 4 ft.
.SUN AND SUN NIGHT...SW winds 15 to 20 kt, becoming W 25 to
30 kt. Seas 3 to 5 ft.
.MON...NW winds 25 to 30 kt. Seas 3 to 5 ft. A chance of light
freezing spray.
.MON NIGHT...NW winds 15 to 20 kt with gusts up to 25 kt. Seas
2 to 4 ft.
Seas are reported as significant wave height, which is the
average of the highest third of the waves. Individual wave
heights may be more than twice the significant wave height.
$$
ANZ254-181900-
Coastal waters from Provincetown MA to Chatham MA to Nantucket MA
out 20 nm-
104 AM EST Thu Dec 18 2025
...STORM WARNING IN EFFECT FROM FRIDAY MORNING THROUGH FRIDAY
AFTERNOON...
.REST OF TONIGHT...NW winds 15 to 20 kt with gusts up to 25 kt.
Seas 3 to 5 ft. Wave Detail: NW 4 ft at 5 seconds and SE 2 ft at
9 seconds.
.THU...SW winds 5 to 10 kt, becoming S 10 to 15 kt with gusts up
to 20 kt in the afternoon. Seas 2 to 4 ft. Wave Detail: SW 3 ft
at 7 seconds and SE 2 ft at 10 seconds.
.THU NIGHT...S winds 15 to 20 kt, increasing to 20 to 25 kt after
midnight. Gusts up to 30 kt. Seas 4 to 6 ft. Wave Detail: S 6 ft
at 6 seconds and SE 1 foot at 10 seconds.
.FRI...S winds 25 to 30 kt, increasing to 30 to 35 kt in the
afternoon. Gusts up to 50 kt. Seas 6 to 9 ft, building to 9 to
13 ft in the afternoon. Wave Detail: S 9 ft at 7 seconds and SE
9 ft at 13 seconds, becoming S 12 ft at 9 seconds and S 6 ft at
6 seconds. Rain. Vsby 1 NM or less.
.FRI NIGHT...W winds 25 to 30 kt with gusts up to 45 kt. Seas
9 to 13 ft, except 12 to 16 ft S and E of Nantucket. Wave Detail:
S 12 ft at 11 seconds and W 8 ft at 6 seconds. A chance of rain
in the evening.
.SAT...W winds 25 to 30 kt with gusts up to 35 kt, diminishing to
10 to 15 kt with gusts up to 20 kt in the afternoon. Seas 7 to
10 ft, subsiding to 5 to 7 ft in the afternoon. Wave Detail: NW
8 ft at 7 seconds and S 7 ft at 11 seconds, becoming W 5 ft at
7 seconds and S 5 ft at 10 seconds.
.SAT NIGHT...SW winds 15 to 20 kt, increasing to 20 to 25 kt
after midnight. Gusts up to 30 kt. Seas 5 to 7 ft.
.SUN...SW winds 20 to 25 kt with gusts up to 30 kt. Seas 5 to
7 ft.
.SUN NIGHT AND MON...NW winds 25 to 30 kt with gusts up to 35 kt.
Seas 6 to 9 ft.
.MON NIGHT...NW winds 15 to 20 kt with gusts up to 25 kt. Seas
4 to 6 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.
$$
ANZ255-181900-
Coastal Waters extending out to 25 nm South of Marthas Vineyard
and Nantucket-
104 AM EST Thu Dec 18 2025
...STORM WARNING IN EFFECT FROM FRIDAY MORNING THROUGH FRIDAY
AFTERNOON...
.REST OF TONIGHT...NW winds 10 to 15 kt with gusts up to 20 kt.
Seas 4 to 6 ft. Wave Detail: SW 6 ft at 8 seconds and SE 1 foot
at 10 seconds.
.THU...S winds 5 to 10 kt, becoming SE 10 to 15 kt with gusts up
to 20 kt in the afternoon. Seas 3 to 4 ft. Wave Detail: SW 4 ft
at 7 seconds and SE 1 foot at 10 seconds.
.THU NIGHT...SE winds 20 to 25 kt, becoming S 25 to 30 kt with
gusts up to 35 kt after midnight. Seas 4 to 6 ft, building to
5 to 8 ft after midnight. Wave Detail: S 6 ft at 7 seconds and SE
1 foot at 10 seconds, becoming S 8 ft at 7 seconds and SE 1 foot
at 14 seconds.
.FRI...S winds 30 to 40 kt with gusts up to 50 kt. Seas 8 to
11 ft, building to 11 to 15 ft in the afternoon. Wave Detail: S
11 ft at 7 seconds and S 11 ft at 14 seconds, becoming S 15 ft at
10 seconds and SW 5 ft at 6 seconds. Rain. Vsby 1 NM or less.
.FRI NIGHT...W winds 30 to 40 kt with gusts up to 45 kt. Seas
11 to 15 ft. Wave Detail: S 15 ft at 11 seconds and W 13 ft at
9 seconds. A chance of rain in the evening.
.SAT...W winds 25 to 30 kt with gusts up to 35 kt, diminishing to
15 to 20 kt in the afternoon. Seas 9 to 12 ft, subsiding to 5 to
8 ft in the afternoon. Wave Detail: W 12 ft at 9 seconds and S
6 ft at 10 seconds, becoming W 7 ft at 8 seconds and S 5 ft at
10 seconds.
.SAT NIGHT...SW winds 20 to 25 kt, increasing to 25 to 30 kt
after midnight. Seas 5 to 7 ft, building to 7 to 10 ft after
midnight.
.SUN AND SUN NIGHT...W winds 25 to 30 kt, becoming NW 25 to
35 kt. Seas 8 to 11 ft.
.MON...NW winds 25 to 35 kt. Seas 7 to 10 ft.
.MON NIGHT...NW winds 20 to 25 kt. Seas 4 to 6 ft.
Seas are reported as significant wave height, which is the
average of the highest third of the waves. Individual wave
heights may be more than twice the significant wave height.
$$
ANZ256-181900-
Coastal Waters from Montauk NY to Marthas Vineyard extending out
to 20 nm South of Block Island-
104 AM EST Thu Dec 18 2025
...GALE WARNING IN EFFECT FROM LATE TONIGHT THROUGH SATURDAY
MORNING...
.REST OF TONIGHT...NW winds 10 to 15 kt with gusts up to 20 kt.
Seas 4 to 6 ft. Wave Detail: SW 6 ft at 7 seconds and SE 1 foot
at 10 seconds.
.THU...S winds 5 to 10 kt, increasing to 10 to 15 kt with gusts
up to 20 kt in the afternoon. Seas 3 to 4 ft. Wave Detail: SW
4 ft at 7 seconds and SE 1 foot at 10 seconds.
.THU NIGHT...S winds 20 to 25 kt, increasing to 25 to 30 kt with
gusts up to 40 kt after midnight. Seas 4 to 6 ft, building to
6 to 9 ft after midnight. Wave Detail: S 6 ft at 7 seconds and SE
1 foot at 10 seconds, becoming S 9 ft at 7 seconds and SE 1 foot
at 11 seconds. A chance of rain after midnight with vsby 1 NM or
less.
.FRI...S winds 30 to 40 kt with gusts up to 45 kt. Seas 9 to
13 ft, building to 12 to 16 ft in the afternoon. Wave Detail: S
13 ft at 11 seconds and S 11 ft at 8 seconds, becoming S 15 ft at
10 seconds and SW 3 ft at 6 seconds. Rain. Vsby 1 NM or less.
.FRI NIGHT...W winds 30 to 40 kt with gusts up to 45 kt. Seas
11 to 15 ft. Wave Detail: S 15 ft at 10 seconds and W 11 ft at
8 seconds.
.SAT...W winds 25 to 30 kt with gusts up to 35 kt, diminishing to
15 to 20 kt in the afternoon. Seas 8 to 11 ft, subsiding to 5 to
8 ft in the afternoon. Wave Detail: NW 9 ft at 8 seconds and S
7 ft at 10 seconds, becoming W 5 ft at 7 seconds and S 5 ft at
10 seconds.
.SAT NIGHT...SW winds 20 to 25 kt, increasing to 25 to 30 kt
after midnight. Seas 5 to 7 ft, building to 7 to 10 ft after
midnight.
.SUN AND SUN NIGHT...W winds 25 to 35 kt with gusts up to 40 kt.
Seas 7 to 10 ft.
.MON...NW winds 25 to 30 kt with gusts up to 35 kt. Seas 5 to
8 ft.
.MON NIGHT...NW winds 15 to 20 kt with gusts up to 25 kt. Seas
4 to 6 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.
$$
ANZ232-181900-
Nantucket Sound-
104 AM EST Thu Dec 18 2025
...STORM WARNING IN EFFECT FROM FRIDAY MORNING THROUGH FRIDAY
AFTERNOON...
.REST OF TONIGHT...W winds 10 to 15 kt. Seas 2 to 3 ft. Wave
Detail: W 2 ft at 5 seconds and SE 1 foot at 10 seconds.
.THU...SW winds 5 to 10 kt, becoming S 10 to 15 kt in the
afternoon. Seas 2 to 3 ft. Wave Detail: S 2 ft at 5 seconds and
SE 1 foot at 10 seconds.
.THU NIGHT...S winds 15 to 20 kt, increasing to 20 to 25 kt after
midnight. Gusts up to 30 kt. Seas 3 to 5 ft. Wave Detail: S 5 ft
at 5 seconds and SE 1 foot at 11 seconds. A chance of rain after
midnight with vsby 1 to 3 NM.
.FRI...S winds 25 to 35 kt, becoming 30 to 35 kt in the
afternoon. Gusts up to 50 kt. Seas 5 to 7 ft, building to 6 to
9 ft in the afternoon. Wave Detail: SE 7 ft at 14 seconds and S
6 ft at 6 seconds, becoming S 7 ft at 9 seconds and S 6 ft at
6 seconds. Rain. Vsby 1 NM or less.
.FRI NIGHT...W winds 30 to 35 kt with gusts up to 40 kt. Seas
6 to 9 ft. Wave Detail: W 6 ft at 5 seconds and S 3 ft at
10 seconds. A chance of rain in the evening.
.SAT...W winds 25 to 30 kt with gusts up to 35 kt, diminishing to
around 15 kt with gusts up to 20 kt in the afternoon. Seas 4 to
6 ft. Wave Detail: W 5 ft at 5 seconds and S 2 ft at 11 seconds.
.SAT NIGHT...SW winds 15 to 20 kt, increasing to 20 to 25 kt
after midnight. Gusts up to 30 kt. Seas 2 to 4 ft, building to
4 to 6 ft after midnight.
.SUN AND SUN NIGHT...SW winds 20 to 25 kt, becoming NW 25 to
30 kt. Seas 4 to 6 ft.
.MON...NW winds 25 to 30 kt. Seas 4 to 6 ft. A chance of light
freezing spray.
.MON NIGHT...NW winds 15 to 20 kt. Seas 2 to 4 ft.
Seas are reported as significant wave height, which is the
average of the highest third of the waves. Individual wave
heights may be more than twice the significant wave height.
$$
ANZ233-181900-
Vineyard Sound-
104 AM EST Thu Dec 18 2025
...STORM WARNING IN EFFECT FROM FRIDAY MORNING THROUGH FRIDAY
AFTERNOON...
.REST OF TONIGHT...NW winds 10 to 15 kt. Seas 2 to 4 ft. Wave
Detail: SW 3 ft at 7 seconds and SE 1 foot at 10 seconds.
.THU...S winds 5 to 10 kt, increasing to 10 to 15 kt with gusts
up to 20 kt in the afternoon. Seas 2 to 3 ft. Wave Detail: SW
3 ft at 7 seconds and SE 1 foot at 10 seconds.
.THU NIGHT...SE winds 15 to 20 kt with gusts up to 25 kt,
becoming S 25 to 30 kt with gusts up to 35 kt after midnight.
Seas 2 to 4 ft, building to 4 to 6 ft after midnight. Wave
Detail: S 4 ft at 6 seconds and SE 1 foot at 10 seconds, becoming
S 5 ft at 5 seconds and SE 1 foot at 13 seconds. A chance of rain
after midnight with vsby 1 NM or less.
.FRI...S winds 30 to 40 kt with gusts up to 50 kt. Seas 7 to
10 ft. Wave Detail: S 10 ft at 13 seconds and S 7 ft at
6 seconds. Rain. Vsby 1 NM or less.
.FRI NIGHT...W winds 30 to 35 kt, becoming 25 to 35 kt after
midnight. Seas 7 to 10 ft. Wave Detail: S 9 ft at 10 seconds and
W 6 ft at 8 seconds. A chance of rain in the evening.
.SAT...W winds 25 to 30 kt with gusts up to 35 kt, diminishing to
10 to 15 kt with gusts up to 20 kt in the afternoon. Seas 5 to
7 ft, subsiding to 3 to 5 ft in the afternoon. Wave Detail: W
6 ft at 8 seconds and S 5 ft at 10 seconds, becoming S 4 ft at
10 seconds and W 3 ft at 7 seconds.
.SAT NIGHT...SW winds 20 to 25 kt, increasing to 25 to 30 kt
after midnight. Seas 4 to 6 ft, building to 5 to 8 ft after
midnight.
.SUN...W winds 25 to 30 kt. Seas 5 to 7 ft.
.SUN NIGHT...NW winds 25 to 30 kt with gusts up to 35 kt. Seas
4 to 6 ft.
.MON...NW winds 25 to 30 kt. Seas 3 to 5 ft. A chance of light
freezing spray.
.MON NIGHT...NW winds 15 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.
$$
ANZ234-181900-
Buzzards Bay-
104 AM EST Thu Dec 18 2025
...STORM WARNING IN EFFECT FROM FRIDAY MORNING THROUGH FRIDAY
AFTERNOON...
.REST OF TONIGHT...NW winds 5 to 10 kt. Seas 2 to 3 ft. Wave
Detail: SW 3 ft at 7 seconds and SE 1 foot at 10 seconds.
.THU...SW winds around 5 kt, becoming S 10 to 15 kt with gusts up
to 20 kt in the afternoon. Seas around 2 ft. Wave Detail: SW 2 ft
at 7 seconds and SE 1 foot at 10 seconds.
.THU NIGHT...S winds 15 to 20 kt with gusts up to 25 kt,
increasing to 25 to 30 kt with gusts up to 35 kt after midnight.
Seas 2 to 3 ft, building to 3 to 5 ft after midnight. Wave
Detail: S 3 ft at 5 seconds and SE 1 foot at 10 seconds, becoming
S 5 ft at 5 seconds and SE 1 foot at 13 seconds. A chance of rain
after midnight with vsby 1 NM or less.
.FRI...S winds 30 to 40 kt, becoming SW 25 to 35 kt in the
afternoon. Gusts up to 50 kt. Seas 5 to 8 ft. Wave Detail: SE
8 ft at 13 seconds and S 6 ft at 5 seconds. Rain. Vsby 1 NM or
less.
.FRI NIGHT...W winds 25 to 30 kt with gusts up to 40 kt. Seas
5 to 7 ft. Wave Detail: S 7 ft at 10 seconds and SW 6 ft at
6 seconds. A chance of rain in the evening.
.SAT...W winds 20 to 25 kt with gusts up to 30 kt, diminishing to
10 to 15 kt with gusts up to 20 kt in the afternoon. Seas 4 to
6 ft, subsiding to 2 to 4 ft in the afternoon. Wave Detail: W
5 ft at 7 seconds and S 5 ft at 10 seconds, becoming W 3 ft at
6 seconds and S 3 ft at 10 seconds.
.SAT NIGHT...SW winds 20 to 25 kt, increasing to 25 to 30 kt with
gusts up to 35 kt after midnight. Seas 4 to 6 ft.
.SUN...W winds 25 to 30 kt. Seas 4 to 6 ft.
.SUN NIGHT...NW winds 20 to 25 kt with gusts up to 30 kt. Seas
3 to 5 ft.
.MON...NW winds 20 to 25 kt with gusts up to 30 kt. Seas 3 to
4 ft. A chance of light freezing spray.
.MON NIGHT...NW 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.
$$
ANZ235-181900-
Rhode Island Sound-
104 AM EST Thu Dec 18 2025
...GALE WARNING IN EFFECT FROM LATE TONIGHT THROUGH SATURDAY
MORNING...
.REST OF TONIGHT...NW winds 10 to 15 kt. Seas 3 to 5 ft. Wave
Detail: SW 5 ft at 8 seconds and SE 1 foot at 10 seconds.
.THU...S winds 5 to 10 kt, increasing to 10 to 15 kt with gusts
up to 20 kt in the afternoon. Seas 2 to 4 ft. Wave Detail: SW
4 ft at 7 seconds and SE 1 foot at 10 seconds.
.THU NIGHT...S winds 15 to 20 kt with gusts up to 25 kt,
increasing to 25 to 30 kt with gusts up to 35 kt after midnight.
Seas 3 to 5 ft, building to 5 to 7 ft after midnight. Wave
Detail: S 5 ft at 6 seconds and SE 1 foot at 10 seconds, becoming
S 7 ft at 7 seconds and SE 1 foot at 12 seconds. A chance of rain
after midnight with vsby 1 NM or less.
.FRI...S winds 30 to 40 kt with gusts up to 50 kt. Seas 8 to
11 ft, building to 9 to 13 ft in the afternoon. Wave Detail: S
11 ft at 8 seconds and S 11 ft at 12 seconds, becoming S 13 ft at
10 seconds and SW 7 ft at 7 seconds. Rain. Vsby 1 NM or less.
.FRI NIGHT...W winds 30 to 35 kt, becoming 25 to 35 kt after
midnight. Seas 9 to 12 ft. Wave Detail: S 12 ft at 10 seconds and
W 7 ft at 7 seconds.
.SAT AND SAT NIGHT...SW winds 25 to 30 kt with gusts up to 35 kt.
Seas 5 to 8 ft. Wave Detail: SW 8 ft at 7 seconds and S 8 ft at
10 seconds.
.SUN...W winds 25 to 30 kt. Seas 6 to 9 ft.
.SUN NIGHT...NW winds 25 to 30 kt with gusts up to 35 kt. Seas
5 to 7 ft.
.MON...NW winds 20 to 25 kt with gusts up to 30 kt. Seas 4 to
6 ft.
.MON NIGHT...NW winds 15 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.
$$
ANZ237-181900-
Block Island Sound-
104 AM EST Thu Dec 18 2025
...GALE WARNING IN EFFECT FROM LATE TONIGHT THROUGH SATURDAY
MORNING...
.REST OF TONIGHT...NW winds 5 to 10 kt. Seas 2 to 4 ft. Wave
Detail: SW 4 ft at 7 seconds and SE 1 foot at 10 seconds.
.THU...S winds 5 to 10 kt, increasing to 10 to 15 kt with gusts
up to 20 kt in the afternoon. Seas 2 to 3 ft. Wave Detail: S 3 ft
at 7 seconds and SE 1 foot at 10 seconds.
.THU NIGHT...S winds 15 to 20 kt with gusts up to 25 kt,
increasing to 20 to 25 kt with gusts up to 35 kt after midnight.
Seas 2 to 4 ft, building to 4 to 6 ft after midnight. Wave
Detail: S 4 ft at 6 seconds and SE 1 foot at 10 seconds, becoming
S 6 ft at 6 seconds and SE 1 foot at 11 seconds.
.FRI...S winds 25 to 35 kt with gusts up to 45 kt. Seas 7 to
10 ft, building to 9 to 12 ft in the afternoon. Wave Detail: S
10 ft at 8 seconds, becoming S 11 ft at 10 seconds and SW 6 ft at
7 seconds. Rain. Vsby 1 NM or less.
.FRI NIGHT...W winds 25 to 30 kt with gusts up to 40 kt. Seas
8 to 11 ft. Wave Detail: S 10 ft at 10 seconds and W 7 ft at
6 seconds.
.SAT AND SAT NIGHT...SW winds 20 to 25 kt with gusts up to 30 kt.
Seas 5 to 7 ft. Wave Detail: SW 7 ft at 6 seconds and S 6 ft at
10 seconds.
.SUN...W winds 20 to 25 kt with gusts up to 30 kt. Seas 5 to
7 ft.
.SUN NIGHT...NW winds 20 to 25 kt with gusts up to 30 kt. Seas
4 to 6 ft.
.MON...NW winds 20 to 25 kt with gusts up to 30 kt. Seas 3 to
5 ft. A chance of light freezing spray.
.MON NIGHT...NW winds 10 to 15 kt with gusts up to 20 kt. Seas
2 to 3 ft.
Seas are reported as significant wave height, which is the
average of the highest third of the waves. Individual wave
heights may be more than twice the significant wave height.
$$
ANZ230-181900-
Boston Harbor-
104 AM EST Thu Dec 18 2025
...GALE WARNING IN EFFECT FROM LATE TONIGHT THROUGH SATURDAY
MORNING...
.REST OF TONIGHT...W winds 10 to 15 kt. Waves around 2 ft.
.THU...SW winds around 5 kt, becoming S 10 to 15 kt with gusts up
to 20 kt in the afternoon. Waves 1 foot or less, then around 2 ft
in the afternoon.
.THU NIGHT...S winds 10 to 15 kt with gusts up to 20 kt,
increasing to 20 to 25 kt with gusts up to 30 kt after midnight.
Waves around 2 ft.
.FRI...S winds 25 to 30 kt with gusts up to 40 kt. Waves around
2 ft. Rain. Vsby 1 NM or less, increasing to 1 to 3 NM in the
afternoon.
.FRI NIGHT...W winds 25 to 30 kt with gusts up to 40 kt. Waves
around 2 ft. A chance of rain in the evening.
.SAT AND SAT NIGHT...SW winds 20 to 25 kt with gusts up to 30 kt.
Waves around 2 ft.
.SUN THROUGH MON NIGHT...NW winds 20 to 25 kt with gusts up to
30 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.
$$
ANZ236-181900-
Narragansett Bay-
104 AM EST Thu Dec 18 2025
...GALE WARNING IN EFFECT FROM LATE TONIGHT THROUGH LATE FRIDAY
NIGHT...
.REST OF TONIGHT...NW winds 5 to 10 kt. Waves 2 to 3 ft.
.THU...SW winds around 5 kt, becoming S 10 to 15 kt in the
afternoon. Waves around 2 ft.
.THU NIGHT...S winds 15 to 20 kt with gusts up to 25 kt,
increasing to 20 to 25 kt with gusts up to 35 kt after midnight.
Waves 2 to 3 ft, building to 3 to 5 ft after midnight. A chance
of rain after midnight with vsby 1 NM or less.
.FRI...S winds 25 to 35 kt with gusts up to 45 kt. Waves 5 to
7 ft, except 7 to 10 ft at the bay entrance. Rain. Vsby 1 NM or
less.
.FRI NIGHT...W winds 20 to 25 kt with gusts up to 35 kt. Waves
5 to 7 ft.
.SAT...W winds 15 to 20 kt with gusts up to 30 kt, diminishing to
10 to 15 kt with gusts up to 20 kt in the afternoon. Waves 2 to
3 ft. At the bay entrance, waves 4 to 6 ft, subsiding to 3 to
4 ft in the afternoon.
.SAT NIGHT...SW winds 15 to 20 kt, increasing to 20 to 25 kt
after midnight. Gusts up to 30 kt. Waves 3 to 5 ft.
.SUN...W winds 20 to 25 kt with gusts up to 30 kt. Waves 3 to
5 ft.
.SUN NIGHT THROUGH MON NIGHT...NW winds 15 to 20 kt with gusts up
to 25 kt. Waves 2 to 3 ft.
Seas are reported as significant wave height, which is the
average of the highest third of the waves. Individual wave
heights may be more than twice the significant wave height.
$$
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CWFBOX
Coastal Waters Forecast for Massachusetts and Rhode Island
National Weather Service Boston/Norton MA
104 AM EST Thu Dec 18 2025
Coastal waters from the Merrimack River MA to Watch Hill RI out
to 25 NM
ANZ200-181900-
104 AM EST Thu Dec 18 2025
.Synopsis for Massachusetts and Rhode Island coastal waters...
A period of gale force SW gusts will develop ahead of a cold front
that moves past the waters overnight. High pres will then cross the
waters Thu. A strong cold front is expected to impact the waters Fri
afternoon and evening. It will be preceded by strong S gale force
gusts Fri, shifting to W gale force gusts Fri night. High pres
should build over the waters Sat afternoon before moving offshore,
then another cold front should move through on Sun.
$$
ANZ250-181900-
Coastal waters east of Ipswich Bay and the Stellwagen Bank
National Marine Sanctuary-
104 AM EST Thu Dec 18 2025
...GALE WARNING IN EFFECT FROM LATE TONIGHT THROUGH SATURDAY
MORNING...
.REST OF TONIGHT...NW winds 15 to 20 kt with gusts up to 25 kt.
Seas 2 to 4 ft. Wave Detail: NW 4 ft at 5 seconds and SE 1 foot
at 10 seconds.
.THU...SW winds 5 to 10 kt, becoming S 15 to 20 kt with gusts up
to 25 kt in the afternoon. Seas 2 to 4 ft. Wave Detail: S 3 ft at
4 seconds and SE 1 foot at 10 seconds.
.THU NIGHT...S winds 15 to 20 kt with gusts up to 25 kt,
increasing to 20 to 25 kt with gusts up to 35 kt after midnight.
Seas 3 to 5 ft, building to 5 to 7 ft after midnight. Wave
Detail: S 4 ft at 5 seconds and SE 1 foot at 10 seconds, becoming
S 6 ft at 6 seconds and SE 1 foot at 11 seconds. A chance of rain
after midnight with vsby 1 NM or less.
.FRI...S winds 25 to 35 kt, increasing to 30 to 40 kt in the
afternoon. Gusts up to 50 kt. Seas 6 to 9 ft, building to 8 to
11 ft in the afternoon. Wave Detail: SE 9 ft at 11 seconds and S
7 ft at 6 seconds, becoming SE 9 ft at 9 seconds and S 6 ft at
6 seconds. Rain. Vsby 1 NM or less.
.FRI NIGHT...W winds 25 to 30 kt with gusts up to 40 kt. Seas
8 to 11 ft. Wave Detail: W 9 ft at 6 seconds and SE 8 ft at
10 seconds. A chance of rain in the evening.
.SAT...W winds 25 to 30 kt with gusts up to 35 kt, diminishing to
around 15 kt with gusts up to 20 kt in the afternoon. Seas 6 to
9 ft, subsiding to 5 to 7 ft in the afternoon. Wave Detail: W
8 ft at 6 seconds and SE 5 ft at 11 seconds, becoming W 5 ft at
6 seconds and SE 4 ft at 11 seconds.
.SAT NIGHT...SW winds 15 to 20 kt, increasing to 20 to 25 kt
after midnight. Gusts up to 30 kt. Seas 4 to 6 ft.
.SUN...W winds 20 to 25 kt with gusts up to 30 kt. Seas 4 to
6 ft.
.SUN NIGHT AND MON...NW winds 25 to 30 kt with gusts up to 35 kt.
Seas 5 to 8 ft.
.MON NIGHT...NW winds 15 to 20 kt with gusts up to 25 kt. Seas
4 to 6 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.
$$
ANZ251-181900-
Massachusetts Bay and Ipswich Bay-
104 AM EST Thu Dec 18 2025
...GALE WARNING IN EFFECT FROM LATE TONIGHT THROUGH SATURDAY
MORNING...
.REST OF TONIGHT...NW winds 10 to 15 kt with gusts up to 20 kt.
Seas around 2 ft. Wave Detail: NW 2 ft at 4 seconds and SE 1 foot
at 10 seconds.
.THU...SW winds 5 to 10 kt, becoming S 15 to 20 kt in the
afternoon. Seas 2 to 3 ft. Wave Detail: S 2 ft at 3 seconds and E
1 foot at 10 seconds.
.THU NIGHT...S winds 15 to 20 kt, increasing to 20 to 25 kt after
midnight. Gusts up to 30 kt. Seas 2 to 3 ft, building to 3 to
5 ft after midnight. Wave Detail: SE 3 ft at 4 seconds and E
1 foot at 10 seconds, becoming SE 5 ft at 5 seconds and SE 1 foot
at 11 seconds. A chance of rain after midnight with vsby 1 NM or
less.
.FRI...S winds 25 to 35 kt with gusts up to 45 kt. Seas 5 to
7 ft. Wave Detail: SE 7 ft at 7 seconds. Rain. Vsby 1 NM or less.
.FRI NIGHT...W winds 25 to 30 kt with gusts up to 40 kt. Seas
4 to 6 ft. Wave Detail: W 5 ft at 5 seconds and SE 5 ft at
10 seconds. A chance of rain in the evening.
.SAT...W winds 20 to 25 kt with gusts up to 30 kt, diminishing to
10 to 15 kt with gusts up to 20 kt in the afternoon. Seas 4 to
6 ft, subsiding to 2 to 4 ft in the afternoon. Wave Detail: W
5 ft at 5 seconds and SE 3 ft at 11 seconds, becoming W 3 ft at
4 seconds and E 3 ft at 11 seconds.
.SAT NIGHT...SW winds 15 to 20 kt, increasing to 20 to 25 kt
after midnight. Gusts up to 30 kt. Seas 2 to 4 ft.
.SUN THROUGH MON...NW winds 25 to 30 kt. Seas 3 to 5 ft.
.MON NIGHT...NW winds 15 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.
$$
ANZ231-181900-
Cape Cod Bay-
104 AM EST Thu Dec 18 2025
...STORM WARNING IN EFFECT FROM FRIDAY MORNING THROUGH FRIDAY
AFTERNOON...
.REST OF TONIGHT...NW winds 10 to 15 kt with gusts up to 20 kt.
Seas around 2 ft. Wave Detail: NW 2 ft at 4 seconds and SE 1 foot
at 10 seconds.
.THU...SW winds 5 to 10 kt, becoming S 10 to 15 kt with gusts up
to 20 kt in the afternoon. Seas 1 foot or less, then around 2 ft
in the afternoon. Wave Detail: NW 1 foot at 4 seconds and SE
1 foot at 10 seconds, becoming S 2 ft at 3 seconds and SE 1 foot
at 8 seconds.
.THU NIGHT...S winds 15 to 20 kt, increasing to 20 to 25 kt after
midnight. Gusts up to 30 kt. Seas 2 to 3 ft. Wave Detail: S 3 ft
at 4 seconds and SE 1 foot at 7 seconds. A chance of rain after
midnight with vsby 1 to 3 NM.
.FRI...S winds 25 to 35 kt. Gusts up to 45 kt, increasing to
55 kt in the afternoon. Seas 4 to 6 ft. Wave Detail: SE 6 ft at
13 seconds and S 5 ft at 5 seconds. Rain. Vsby 1 NM or less.
.FRI NIGHT...W winds 25 to 30 kt with gusts up to 40 kt. Seas
4 to 6 ft. Wave Detail: W 5 ft at 5 seconds and S 4 ft at
10 seconds. A chance of rain in the evening.
.SAT...W winds 20 to 25 kt with gusts up to 30 kt, diminishing to
10 to 15 kt with gusts up to 20 kt in the afternoon. Seas 3 to
5 ft. Wave Detail: NW 5 ft at 6 seconds and SE 3 ft at
11 seconds.
.SAT NIGHT...SW winds 15 to 20 kt with gusts up to 30 kt. Seas
2 to 4 ft.
.SUN AND SUN NIGHT...SW winds 15 to 20 kt, becoming W 25 to
30 kt. Seas 3 to 5 ft.
.MON...NW winds 25 to 30 kt. Seas 3 to 5 ft. A chance of light
freezing spray.
.MON NIGHT...NW winds 15 to 20 kt with gusts up to 25 kt. Seas
2 to 4 ft.
Seas are reported as significant wave height, which is the
average of the highest third of the waves. Individual wave
heights may be more than twice the significant wave height.
$$
ANZ254-181900-
Coastal waters from Provincetown MA to Chatham MA to Nantucket MA
out 20 nm-
104 AM EST Thu Dec 18 2025
...STORM WARNING IN EFFECT FROM FRIDAY MORNING THROUGH FRIDAY
AFTERNOON...
.REST OF TONIGHT...NW winds 15 to 20 kt with gusts up to 25 kt.
Seas 3 to 5 ft. Wave Detail: NW 4 ft at 5 seconds and SE 2 ft at
9 seconds.
.THU...SW winds 5 to 10 kt, becoming S 10 to 15 kt with gusts up
to 20 kt in the afternoon. Seas 2 to 4 ft. Wave Detail: SW 3 ft
at 7 seconds and SE 2 ft at 10 seconds.
.THU NIGHT...S winds 15 to 20 kt, increasing to 20 to 25 kt after
midnight. Gusts up to 30 kt. Seas 4 to 6 ft. Wave Detail: S 6 ft
at 6 seconds and SE 1 foot at 10 seconds.
.FRI...S winds 25 to 30 kt, increasing to 30 to 35 kt in the
afternoon. Gusts up to 50 kt. Seas 6 to 9 ft, building to 9 to
13 ft in the afternoon. Wave Detail: S 9 ft at 7 seconds and SE
9 ft at 13 seconds, becoming S 12 ft at 9 seconds and S 6 ft at
6 seconds. Rain. Vsby 1 NM or less.
.FRI NIGHT...W winds 25 to 30 kt with gusts up to 45 kt. Seas
9 to 13 ft, except 12 to 16 ft S and E of Nantucket. Wave Detail:
S 12 ft at 11 seconds and W 8 ft at 6 seconds. A chance of rain
in the evening.
.SAT...W winds 25 to 30 kt with gusts up to 35 kt, diminishing to
10 to 15 kt with gusts up to 20 kt in the afternoon. Seas 7 to
10 ft, subsiding to 5 to 7 ft in the afternoon. Wave Detail: NW
8 ft at 7 seconds and S 7 ft at 11 seconds, becoming W 5 ft at
7 seconds and S 5 ft at 10 seconds.
.SAT NIGHT...SW winds 15 to 20 kt, increasing to 20 to 25 kt
after midnight. Gusts up to 30 kt. Seas 5 to 7 ft.
.SUN...SW winds 20 to 25 kt with gusts up to 30 kt. Seas 5 to
7 ft.
.SUN NIGHT AND MON...NW winds 25 to 30 kt with gusts up to 35 kt.
Seas 6 to 9 ft.
.MON NIGHT...NW winds 15 to 20 kt with gusts up to 25 kt. Seas
4 to 6 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.
$$
ANZ255-181900-
Coastal Waters extending out to 25 nm South of Marthas Vineyard
and Nantucket-
104 AM EST Thu Dec 18 2025
...STORM WARNING IN EFFECT FROM FRIDAY MORNING THROUGH FRIDAY
AFTERNOON...
.REST OF TONIGHT...NW winds 10 to 15 kt with gusts up to 20 kt.
Seas 4 to 6 ft. Wave Detail: SW 6 ft at 8 seconds and SE 1 foot
at 10 seconds.
.THU...S winds 5 to 10 kt, becoming SE 10 to 15 kt with gusts up
to 20 kt in the afternoon. Seas 3 to 4 ft. Wave Detail: SW 4 ft
at 7 seconds and SE 1 foot at 10 seconds.
.THU NIGHT...SE winds 20 to 25 kt, becoming S 25 to 30 kt with
gusts up to 35 kt after midnight. Seas 4 to 6 ft, building to
5 to 8 ft after midnight. Wave Detail: S 6 ft at 7 seconds and SE
1 foot at 10 seconds, becoming S 8 ft at 7 seconds and SE 1 foot
at 14 seconds.
.FRI...S winds 30 to 40 kt with gusts up to 50 kt. Seas 8 to
11 ft, building to 11 to 15 ft in the afternoon. Wave Detail: S
11 ft at 7 seconds and S 11 ft at 14 seconds, becoming S 15 ft at
10 seconds and SW 5 ft at 6 seconds. Rain. Vsby 1 NM or less.
.FRI NIGHT...W winds 30 to 40 kt with gusts up to 45 kt. Seas
11 to 15 ft. Wave Detail: S 15 ft at 11 seconds and W 13 ft at
9 seconds. A chance of rain in the evening.
.SAT...W winds 25 to 30 kt with gusts up to 35 kt, diminishing to
15 to 20 kt in the afternoon. Seas 9 to 12 ft, subsiding to 5 to
8 ft in the afternoon. Wave Detail: W 12 ft at 9 seconds and S
6 ft at 10 seconds, becoming W 7 ft at 8 seconds and S 5 ft at
10 seconds.
.SAT NIGHT...SW winds 20 to 25 kt, increasing to 25 to 30 kt
after midnight. Seas 5 to 7 ft, building to 7 to 10 ft after
midnight.
.SUN AND SUN NIGHT...W winds 25 to 30 kt, becoming NW 25 to
35 kt. Seas 8 to 11 ft.
.MON...NW winds 25 to 35 kt. Seas 7 to 10 ft.
.MON NIGHT...NW winds 20 to 25 kt. Seas 4 to 6 ft.
Seas are reported as significant wave height, which is the
average of the highest third of the waves. Individual wave
heights may be more than twice the significant wave height.
$$
ANZ256-181900-
Coastal Waters from Montauk NY to Marthas Vineyard extending out
to 20 nm South of Block Island-
104 AM EST Thu Dec 18 2025
...GALE WARNING IN EFFECT FROM LATE TONIGHT THROUGH SATURDAY
MORNING...
.REST OF TONIGHT...NW winds 10 to 15 kt with gusts up to 20 kt.
Seas 4 to 6 ft. Wave Detail: SW 6 ft at 7 seconds and SE 1 foot
at 10 seconds.
.THU...S winds 5 to 10 kt, increasing to 10 to 15 kt with gusts
up to 20 kt in the afternoon. Seas 3 to 4 ft. Wave Detail: SW
4 ft at 7 seconds and SE 1 foot at 10 seconds.
.THU NIGHT...S winds 20 to 25 kt, increasing to 25 to 30 kt with
gusts up to 40 kt after midnight. Seas 4 to 6 ft, building to
6 to 9 ft after midnight. Wave Detail: S 6 ft at 7 seconds and SE
1 foot at 10 seconds, becoming S 9 ft at 7 seconds and SE 1 foot
at 11 seconds. A chance of rain after midnight with vsby 1 NM or
less.
.FRI...S winds 30 to 40 kt with gusts up to 45 kt. Seas 9 to
13 ft, building to 12 to 16 ft in the afternoon. Wave Detail: S
13 ft at 11 seconds and S 11 ft at 8 seconds, becoming S 15 ft at
10 seconds and SW 3 ft at 6 seconds. Rain. Vsby 1 NM or less.
.FRI NIGHT...W winds 30 to 40 kt with gusts up to 45 kt. Seas
11 to 15 ft. Wave Detail: S 15 ft at 10 seconds and W 11 ft at
8 seconds.
.SAT...W winds 25 to 30 kt with gusts up to 35 kt, diminishing to
15 to 20 kt in the afternoon. Seas 8 to 11 ft, subsiding to 5 to
8 ft in the afternoon. Wave Detail: NW 9 ft at 8 seconds and S
7 ft at 10 seconds, becoming W 5 ft at 7 seconds and S 5 ft at
10 seconds.
.SAT NIGHT...SW winds 20 to 25 kt, increasing to 25 to 30 kt
after midnight. Seas 5 to 7 ft, building to 7 to 10 ft after
midnight.
.SUN AND SUN NIGHT...W winds 25 to 35 kt with gusts up to 40 kt.
Seas 7 to 10 ft.
.MON...NW winds 25 to 30 kt with gusts up to 35 kt. Seas 5 to
8 ft.
.MON NIGHT...NW winds 15 to 20 kt with gusts up to 25 kt. Seas
4 to 6 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.
$$
ANZ232-181900-
Nantucket Sound-
104 AM EST Thu Dec 18 2025
...STORM WARNING IN EFFECT FROM FRIDAY MORNING THROUGH FRIDAY
AFTERNOON...
.REST OF TONIGHT...W winds 10 to 15 kt. Seas 2 to 3 ft. Wave
Detail: W 2 ft at 5 seconds and SE 1 foot at 10 seconds.
.THU...SW winds 5 to 10 kt, becoming S 10 to 15 kt in the
afternoon. Seas 2 to 3 ft. Wave Detail: S 2 ft at 5 seconds and
SE 1 foot at 10 seconds.
.THU NIGHT...S winds 15 to 20 kt, increasing to 20 to 25 kt after
midnight. Gusts up to 30 kt. Seas 3 to 5 ft. Wave Detail: S 5 ft
at 5 seconds and SE 1 foot at 11 seconds. A chance of rain after
midnight with vsby 1 to 3 NM.
.FRI...S winds 25 to 35 kt, becoming 30 to 35 kt in the
afternoon. Gusts up to 50 kt. Seas 5 to 7 ft, building to 6 to
9 ft in the afternoon. Wave Detail: SE 7 ft at 14 seconds and S
6 ft at 6 seconds, becoming S 7 ft at 9 seconds and S 6 ft at
6 seconds. Rain. Vsby 1 NM or less.
.FRI NIGHT...W winds 30 to 35 kt with gusts up to 40 kt. Seas
6 to 9 ft. Wave Detail: W 6 ft at 5 seconds and S 3 ft at
10 seconds. A chance of rain in the evening.
.SAT...W winds 25 to 30 kt with gusts up to 35 kt, diminishing to
around 15 kt with gusts up to 20 kt in the afternoon. Seas 4 to
6 ft. Wave Detail: W 5 ft at 5 seconds and S 2 ft at 11 seconds.
.SAT NIGHT...SW winds 15 to 20 kt, increasing to 20 to 25 kt
after midnight. Gusts up to 30 kt. Seas 2 to 4 ft, building to
4 to 6 ft after midnight.
.SUN AND SUN NIGHT...SW winds 20 to 25 kt, becoming NW 25 to
30 kt. Seas 4 to 6 ft.
.MON...NW winds 25 to 30 kt. Seas 4 to 6 ft. A chance of light
freezing spray.
.MON NIGHT...NW winds 15 to 20 kt. Seas 2 to 4 ft.
Seas are reported as significant wave height, which is the
average of the highest third of the waves. Individual wave
heights may be more than twice the significant wave height.
$$
ANZ233-181900-
Vineyard Sound-
104 AM EST Thu Dec 18 2025
...STORM WARNING IN EFFECT FROM FRIDAY MORNING THROUGH FRIDAY
AFTERNOON...
.REST OF TONIGHT...NW winds 10 to 15 kt. Seas 2 to 4 ft. Wave
Detail: SW 3 ft at 7 seconds and SE 1 foot at 10 seconds.
.THU...S winds 5 to 10 kt, increasing to 10 to 15 kt with gusts
up to 20 kt in the afternoon. Seas 2 to 3 ft. Wave Detail: SW
3 ft at 7 seconds and SE 1 foot at 10 seconds.
.THU NIGHT...SE winds 15 to 20 kt with gusts up to 25 kt,
becoming S 25 to 30 kt with gusts up to 35 kt after midnight.
Seas 2 to 4 ft, building to 4 to 6 ft after midnight. Wave
Detail: S 4 ft at 6 seconds and SE 1 foot at 10 seconds, becoming
S 5 ft at 5 seconds and SE 1 foot at 13 seconds. A chance of rain
after midnight with vsby 1 NM or less.
.FRI...S winds 30 to 40 kt with gusts up to 50 kt. Seas 7 to
10 ft. Wave Detail: S 10 ft at 13 seconds and S 7 ft at
6 seconds. Rain. Vsby 1 NM or less.
.FRI NIGHT...W winds 30 to 35 kt, becoming 25 to 35 kt after
midnight. Seas 7 to 10 ft. Wave Detail: S 9 ft at 10 seconds and
W 6 ft at 8 seconds. A chance of rain in the evening.
.SAT...W winds 25 to 30 kt with gusts up to 35 kt, diminishing to
10 to 15 kt with gusts up to 20 kt in the afternoon. Seas 5 to
7 ft, subsiding to 3 to 5 ft in the afternoon. Wave Detail: W
6 ft at 8 seconds and S 5 ft at 10 seconds, becoming S 4 ft at
10 seconds and W 3 ft at 7 seconds.
.SAT NIGHT...SW winds 20 to 25 kt, increasing to 25 to 30 kt
after midnight. Seas 4 to 6 ft, building to 5 to 8 ft after
midnight.
.SUN...W winds 25 to 30 kt. Seas 5 to 7 ft.
.SUN NIGHT...NW winds 25 to 30 kt with gusts up to 35 kt. Seas
4 to 6 ft.
.MON...NW winds 25 to 30 kt. Seas 3 to 5 ft. A chance of light
freezing spray.
.MON NIGHT...NW winds 15 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.
$$
ANZ234-181900-
Buzzards Bay-
104 AM EST Thu Dec 18 2025
...STORM WARNING IN EFFECT FROM FRIDAY MORNING THROUGH FRIDAY
AFTERNOON...
.REST OF TONIGHT...NW winds 5 to 10 kt. Seas 2 to 3 ft. Wave
Detail: SW 3 ft at 7 seconds and SE 1 foot at 10 seconds.
.THU...SW winds around 5 kt, becoming S 10 to 15 kt with gusts up
to 20 kt in the afternoon. Seas around 2 ft. Wave Detail: SW 2 ft
at 7 seconds and SE 1 foot at 10 seconds.
.THU NIGHT...S winds 15 to 20 kt with gusts up to 25 kt,
increasing to 25 to 30 kt with gusts up to 35 kt after midnight.
Seas 2 to 3 ft, building to 3 to 5 ft after midnight. Wave
Detail: S 3 ft at 5 seconds and SE 1 foot at 10 seconds, becoming
S 5 ft at 5 seconds and SE 1 foot at 13 seconds. A chance of rain
after midnight with vsby 1 NM or less.
.FRI...S winds 30 to 40 kt, becoming SW 25 to 35 kt in the
afternoon. Gusts up to 50 kt. Seas 5 to 8 ft. Wave Detail: SE
8 ft at 13 seconds and S 6 ft at 5 seconds. Rain. Vsby 1 NM or
less.
.FRI NIGHT...W winds 25 to 30 kt with gusts up to 40 kt. Seas
5 to 7 ft. Wave Detail: S 7 ft at 10 seconds and SW 6 ft at
6 seconds. A chance of rain in the evening.
.SAT...W winds 20 to 25 kt with gusts up to 30 kt, diminishing to
10 to 15 kt with gusts up to 20 kt in the afternoon. Seas 4 to
6 ft, subsiding to 2 to 4 ft in the afternoon. Wave Detail: W
5 ft at 7 seconds and S 5 ft at 10 seconds, becoming W 3 ft at
6 seconds and S 3 ft at 10 seconds.
.SAT NIGHT...SW winds 20 to 25 kt, increasing to 25 to 30 kt with
gusts up to 35 kt after midnight. Seas 4 to 6 ft.
.SUN...W winds 25 to 30 kt. Seas 4 to 6 ft.
.SUN NIGHT...NW winds 20 to 25 kt with gusts up to 30 kt. Seas
3 to 5 ft.
.MON...NW winds 20 to 25 kt with gusts up to 30 kt. Seas 3 to
4 ft. A chance of light freezing spray.
.MON NIGHT...NW 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.
$$
ANZ235-181900-
Rhode Island Sound-
104 AM EST Thu Dec 18 2025
...GALE WARNING IN EFFECT FROM LATE TONIGHT THROUGH SATURDAY
MORNING...
.REST OF TONIGHT...NW winds 10 to 15 kt. Seas 3 to 5 ft. Wave
Detail: SW 5 ft at 8 seconds and SE 1 foot at 10 seconds.
.THU...S winds 5 to 10 kt, increasing to 10 to 15 kt with gusts
up to 20 kt in the afternoon. Seas 2 to 4 ft. Wave Detail: SW
4 ft at 7 seconds and SE 1 foot at 10 seconds.
.THU NIGHT...S winds 15 to 20 kt with gusts up to 25 kt,
increasing to 25 to 30 kt with gusts up to 35 kt after midnight.
Seas 3 to 5 ft, building to 5 to 7 ft after midnight. Wave
Detail: S 5 ft at 6 seconds and SE 1 foot at 10 seconds, becoming
S 7 ft at 7 seconds and SE 1 foot at 12 seconds. A chance of rain
after midnight with vsby 1 NM or less.
.FRI...S winds 30 to 40 kt with gusts up to 50 kt. Seas 8 to
11 ft, building to 9 to 13 ft in the afternoon. Wave Detail: S
11 ft at 8 seconds and S 11 ft at 12 seconds, becoming S 13 ft at
10 seconds and SW 7 ft at 7 seconds. Rain. Vsby 1 NM or less.
.FRI NIGHT...W winds 30 to 35 kt, becoming 25 to 35 kt after
midnight. Seas 9 to 12 ft. Wave Detail: S 12 ft at 10 seconds and
W 7 ft at 7 seconds.
.SAT AND SAT NIGHT...SW winds 25 to 30 kt with gusts up to 35 kt.
Seas 5 to 8 ft. Wave Detail: SW 8 ft at 7 seconds and S 8 ft at
10 seconds.
.SUN...W winds 25 to 30 kt. Seas 6 to 9 ft.
.SUN NIGHT...NW winds 25 to 30 kt with gusts up to 35 kt. Seas
5 to 7 ft.
.MON...NW winds 20 to 25 kt with gusts up to 30 kt. Seas 4 to
6 ft.
.MON NIGHT...NW winds 15 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.
$$
ANZ237-181900-
Block Island Sound-
104 AM EST Thu Dec 18 2025
...GALE WARNING IN EFFECT FROM LATE TONIGHT THROUGH SATURDAY
MORNING...
.REST OF TONIGHT...NW winds 5 to 10 kt. Seas 2 to 4 ft. Wave
Detail: SW 4 ft at 7 seconds and SE 1 foot at 10 seconds.
.THU...S winds 5 to 10 kt, increasing to 10 to 15 kt with gusts
up to 20 kt in the afternoon. Seas 2 to 3 ft. Wave Detail: S 3 ft
at 7 seconds and SE 1 foot at 10 seconds.
.THU NIGHT...S winds 15 to 20 kt with gusts up to 25 kt,
increasing to 20 to 25 kt with gusts up to 35 kt after midnight.
Seas 2 to 4 ft, building to 4 to 6 ft after midnight. Wave
Detail: S 4 ft at 6 seconds and SE 1 foot at 10 seconds, becoming
S 6 ft at 6 seconds and SE 1 foot at 11 seconds.
.FRI...S winds 25 to 35 kt with gusts up to 45 kt. Seas 7 to
10 ft, building to 9 to 12 ft in the afternoon. Wave Detail: S
10 ft at 8 seconds, becoming S 11 ft at 10 seconds and SW 6 ft at
7 seconds. Rain. Vsby 1 NM or less.
.FRI NIGHT...W winds 25 to 30 kt with gusts up to 40 kt. Seas
8 to 11 ft. Wave Detail: S 10 ft at 10 seconds and W 7 ft at
6 seconds.
.SAT AND SAT NIGHT...SW winds 20 to 25 kt with gusts up to 30 kt.
Seas 5 to 7 ft. Wave Detail: SW 7 ft at 6 seconds and S 6 ft at
10 seconds.
.SUN...W winds 20 to 25 kt with gusts up to 30 kt. Seas 5 to
7 ft.
.SUN NIGHT...NW winds 20 to 25 kt with gusts up to 30 kt. Seas
4 to 6 ft.
.MON...NW winds 20 to 25 kt with gusts up to 30 kt. Seas 3 to
5 ft. A chance of light freezing spray.
.MON NIGHT...NW winds 10 to 15 kt with gusts up to 20 kt. Seas
2 to 3 ft.
Seas are reported as significant wave height, which is the
average of the highest third of the waves. Individual wave
heights may be more than twice the significant wave height.
$$
ANZ230-181900-
Boston Harbor-
104 AM EST Thu Dec 18 2025
...GALE WARNING IN EFFECT FROM LATE TONIGHT THROUGH SATURDAY
MORNING...
.REST OF TONIGHT...W winds 10 to 15 kt. Waves around 2 ft.
.THU...SW winds around 5 kt, becoming S 10 to 15 kt with gusts up
to 20 kt in the afternoon. Waves 1 foot or less, then around 2 ft
in the afternoon.
.THU NIGHT...S winds 10 to 15 kt with gusts up to 20 kt,
increasing to 20 to 25 kt with gusts up to 30 kt after midnight.
Waves around 2 ft.
.FRI...S winds 25 to 30 kt with gusts up to 40 kt. Waves around
2 ft. Rain. Vsby 1 NM or less, increasing to 1 to 3 NM in the
afternoon.
.FRI NIGHT...W winds 25 to 30 kt with gusts up to 40 kt. Waves
around 2 ft. A chance of rain in the evening.
.SAT AND SAT NIGHT...SW winds 20 to 25 kt with gusts up to 30 kt.
Waves around 2 ft.
.SUN THROUGH MON NIGHT...NW winds 20 to 25 kt with gusts up to
30 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.
$$
ANZ236-181900-
Narragansett Bay-
104 AM EST Thu Dec 18 2025
...GALE WARNING IN EFFECT FROM LATE TONIGHT THROUGH LATE FRIDAY
NIGHT...
.REST OF TONIGHT...NW winds 5 to 10 kt. Waves 2 to 3 ft.
.THU...SW winds around 5 kt, becoming S 10 to 15 kt in the
afternoon. Waves around 2 ft.
.THU NIGHT...S winds 15 to 20 kt with gusts up to 25 kt,
increasing to 20 to 25 kt with gusts up to 35 kt after midnight.
Waves 2 to 3 ft, building to 3 to 5 ft after midnight. A chance
of rain after midnight with vsby 1 NM or less.
.FRI...S winds 25 to 35 kt with gusts up to 45 kt. Waves 5 to
7 ft, except 7 to 10 ft at the bay entrance. Rain. Vsby 1 NM or
less.
.FRI NIGHT...W winds 20 to 25 kt with gusts up to 35 kt. Waves
5 to 7 ft.
.SAT...W winds 15 to 20 kt with gusts up to 30 kt, diminishing to
10 to 15 kt with gusts up to 20 kt in the afternoon. Waves 2 to
3 ft. At the bay entrance, waves 4 to 6 ft, subsiding to 3 to
4 ft in the afternoon.
.SAT NIGHT...SW winds 15 to 20 kt, increasing to 20 to 25 kt
after midnight. Gusts up to 30 kt. Waves 3 to 5 ft.
.SUN...W winds 20 to 25 kt with gusts up to 30 kt. Waves 3 to
5 ft.
.SUN NIGHT THROUGH MON NIGHT...NW winds 15 to 20 kt with gusts up
to 25 kt. Waves 2 to 3 ft.
Seas are reported as significant wave height, which is the
average of the highest third of the waves. Individual wave
heights may be more than twice the significant wave height.
$$
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