FZUS51 KBOX 201204
CWFBOX
Coastal Waters Forecast for Massachusetts and Rhode Island
National Weather Service Boston/Norton MA
704 AM EST Sat Dec 20 2025
Coastal waters from the Merrimack River MA to Watch Hill RI out
to 25 NM
ANZ200-210100-
704 AM EST Sat Dec 20 2025
.Synopsis for Massachusetts and Rhode Island coastal waters...
High pres builds over the waters this afternoon before moving
offshore tonight. Another cold front approaches tonight and moves
across the waters Sun afternoon. A period of pre-frontal SW gales is
possible tonight into Sun morning with continued gusty W-NW winds
late Sun into Sun night. High pres builds S of the waters late Mon
into Mon night, then a warm front moves into the waters Tue. Low
pres develops on the front east of New Eng Tue night and moves
offshore, then high pres builds in from the west Wed.
$$
ANZ250-210100-
Coastal waters east of Ipswich Bay and the Stellwagen Bank
National Marine Sanctuary-
704 AM EST Sat Dec 20 2025
...GALE WARNING IN EFFECT UNTIL 9 AM EST THIS MORNING...
.TODAY...W winds 25 to 30 kt with gusts up to 35 kt, diminishing
to 10 to 15 kt with gusts up to 20 kt this afternoon. Seas 7 to
10 ft, subsiding to 5 to 7 ft this afternoon. Wave Detail: W 8 ft
at 6 seconds and SE 6 ft at 11 seconds, becoming W 5 ft at
6 seconds and SE 5 ft at 11 seconds.
.TONIGHT...SW winds 20 to 25 kt, increasing to 25 to 30 kt after
midnight. Seas 4 to 6 ft. Wave Detail: SW 6 ft at 5 seconds and
SE 4 ft at 11 seconds.
.SUN...W winds 20 to 25 kt with gusts up to 30 kt. Seas 5 to
7 ft. Wave Detail: SW 6 ft at 5 seconds and SE 3 ft at
10 seconds.
.SUN NIGHT...NW winds 20 to 25 kt with gusts up to 30 kt. Seas
5 to 8 ft. Wave Detail: NW 6 ft at 5 seconds and SE 3 ft at
10 seconds.
.MON...NW winds 20 to 25 kt, diminishing to 15 to 20 kt in the
afternoon. Gusts up to 30 kt. Seas 5 to 8 ft, subsiding to 4 to
6 ft in the afternoon. Wave Detail: NW 6 ft at 6 seconds and E
2 ft at 10 seconds, becoming NW 5 ft at 5 seconds and E 2 ft at
10 seconds.
.MON NIGHT...W winds 10 to 15 kt with gusts up to 20 kt. Seas
2 to 4 ft. Wave Detail: W 4 ft at 5 seconds and E 2 ft at
10 seconds.
.TUE...SW winds 15 to 20 kt with gusts up to 25 kt. Seas 2 to
4 ft. Rain with a chance of snow.
.TUE NIGHT...W winds 20 to 25 kt with gusts up to 30 kt. Seas
3 to 5 ft. A chance of rain.
.WED...NW winds 20 to 25 kt with gusts up to 30 kt. Seas 4 to
6 ft.
.WED NIGHT...NW winds 10 to 15 kt with gusts up to 20 kt. Seas
3 to 5 ft.
Seas are reported as significant wave height, which is the
average of the highest third of the waves. Individual wave
heights may be more than twice the significant wave height.
$$
ANZ251-210100-
Massachusetts Bay and Ipswich Bay-
704 AM EST Sat Dec 20 2025
...SMALL CRAFT ADVISORY IN EFFECT THROUGH SUNDAY MORNING...
.TODAY...W winds 20 to 25 kt with gusts up to 35 kt, diminishing
to 10 to 15 kt this afternoon. Seas 4 to 6 ft. Wave Detail: W
5 ft at 5 seconds and SE 4 ft at 12 seconds.
.TONIGHT...SW winds 20 to 25 kt with gusts up to 35 kt. Seas 2 to
4 ft. Wave Detail: SW 4 ft at 4 seconds and E 3 ft at 11 seconds.
.SUN...SW winds 15 to 20 kt, becoming W 20 to 25 kt in the
afternoon. Gusts up to 30 kt. Seas 3 to 4 ft. Wave Detail: SW
4 ft at 4 seconds and E 2 ft at 10 seconds.
.SUN NIGHT...NW winds 20 to 25 kt with gusts up to 30 kt. Seas
3 to 5 ft. Wave Detail: NW 4 ft at 4 seconds and E 2 ft at
10 seconds.
.MON...NW winds 20 to 25 kt, diminishing to 15 to 20 kt in the
afternoon. Seas 3 to 5 ft. Wave Detail: NW 4 ft at 4 seconds and
E 2 ft at 10 seconds.
.MON NIGHT...W winds 10 to 15 kt. Gusts up to 20 kt in the
evening. Seas 2 to 3 ft. Wave Detail: NW 3 ft at 4 seconds and NE
2 ft at 8 seconds.
.TUE...SW winds 15 to 20 kt with gusts up to 25 kt. Seas 2 to
3 ft. Snow with rain likely.
.TUE NIGHT...W winds 20 to 25 kt. Seas 2 to 3 ft. A chance of
rain.
.WED AND WED NIGHT...NW winds 20 to 25 kt, becoming W 10 to
15 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.
$$
ANZ231-210100-
Cape Cod Bay-
704 AM EST Sat Dec 20 2025
...SMALL CRAFT ADVISORY IN EFFECT THROUGH SUNDAY MORNING...
.TODAY...W winds 20 to 25 kt with gusts up to 30 kt, diminishing
to 10 to 15 kt this afternoon. Seas 3 to 5 ft. Wave Detail: NW
4 ft at 6 seconds and SE 3 ft at 11 seconds.
.TONIGHT...SW winds 15 to 20 kt, increasing to 20 to 25 kt after
midnight. Gusts up to 30 kt. Seas 2 to 4 ft. Wave Detail: SW 3 ft
at 4 seconds and SE 1 foot at 9 seconds.
.SUN...W winds 15 to 20 kt with gusts up to 30 kt. Seas 3 to
4 ft. Wave Detail: SW 3 ft at 4 seconds and SE 2 ft at 8 seconds.
.SUN NIGHT...NW winds 20 to 25 kt with gusts up to 30 kt. Seas
3 to 5 ft. Wave Detail: NW 5 ft at 5 seconds and SE 2 ft at
10 seconds.
.MON...NW winds 20 to 25 kt, diminishing to 15 to 20 kt in the
afternoon. Gusts up to 30 kt. Seas 3 to 5 ft. Wave Detail: NW
5 ft at 6 seconds and E 1 foot at 10 seconds.
.MON NIGHT...W winds 10 to 15 kt. Gusts up to 20 kt in the
evening. Seas 2 to 3 ft. Wave Detail: NW 3 ft at 6 seconds and NE
1 foot at 9 seconds.
.TUE...SW winds 15 to 20 kt with gusts up to 25 kt. Seas 2 to
4 ft. Rain.
.TUE NIGHT...W winds 20 to 25 kt. Seas 2 to 3 ft. A chance of
rain.
.WED AND WED NIGHT...NW winds 20 to 25 kt with gusts up to 30 kt,
diminishing to 10 to 15 kt with gusts up to 20 kt. Seas 2 to
4 ft.
Seas are reported as significant wave height, which is the
average of the highest third of the waves. Individual wave
heights may be more than twice the significant wave height.
$$
ANZ254-210100-
Coastal waters from Provincetown MA to Chatham MA to Nantucket MA
out 20 nm-
704 AM EST Sat Dec 20 2025
...GALE WARNING IN EFFECT UNTIL 9 AM EST THIS MORNING...
.TODAY...NW winds 25 to 30 kt with gusts up to 35 kt, becoming W
10 to 15 kt with gusts up to 20 kt this afternoon. Seas 8 to
11 ft, subsiding to 5 to 8 ft this afternoon. Wave Detail: S 8 ft
at 11 seconds and NW 7 ft at 6 seconds, becoming S 7 ft at
11 seconds and NW 5 ft at 6 seconds.
.TONIGHT...SW 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 5 to 7 ft. Wave Detail: SW 6 ft at 6 seconds and S 5 ft at
10 seconds.
.SUN...SW winds 20 to 25 kt, becoming W 15 to 20 kt in the
afternoon. Gusts up to 30 kt. Seas 5 to 7 ft. Wave Detail: SW
6 ft at 6 seconds and SE 4 ft at 9 seconds.
.SUN NIGHT...NW winds 20 to 25 kt with gusts up to 30 kt. Seas
5 to 8 ft. Wave Detail: NW 7 ft at 6 seconds and SE 4 ft at
10 seconds.
.MON...NW winds 20 to 25 kt, diminishing to 15 to 20 kt in the
afternoon. Gusts up to 30 kt. Seas 5 to 8 ft. Wave Detail: NW
7 ft at 7 seconds and E 2 ft at 10 seconds.
.MON NIGHT...NW winds 15 to 20 kt, becoming W 10 to 15 kt after
midnight. Seas 3 to 5 ft. Wave Detail: NW 5 ft at 6 seconds and E
2 ft at 9 seconds.
.TUE...SW winds 15 to 20 kt with gusts up to 25 kt. Seas 3 to
5 ft. Rain.
.TUE NIGHT...W winds 20 to 25 kt with gusts up to 30 kt. Seas
5 to 7 ft, except 8 to 11 ft S and E of Nantucket. A chance of
rain.
.WED...NW winds 20 to 25 kt with gusts up to 30 kt. Seas 5 to
7 ft.
.WED NIGHT...NW winds 10 to 15 kt with gusts up to 20 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.
$$
ANZ255-210100-
Coastal Waters extending out to 25 nm South of Marthas Vineyard
and Nantucket-
704 AM EST Sat Dec 20 2025
...SMALL CRAFT ADVISORY IN EFFECT THROUGH SUNDAY MORNING...
.TODAY...NW winds 20 to 25 kt with gusts up to 30 kt, becoming W
10 to 15 kt this afternoon. Seas 9 to 13 ft, subsiding to 6 to
9 ft this afternoon. Wave Detail: SW 12 ft at 11 seconds and W
7 ft at 7 seconds, becoming SW 8 ft at 11 seconds and NW 2 ft at
6 seconds.
.TONIGHT...SW winds 15 to 20 kt with gusts up to 25 kt,
increasing to 25 to 30 kt with gusts up to 35 kt after midnight.
Seas 4 to 6 ft, building to 6 to 9 ft after midnight. Wave
Detail: SW 6 ft at 10 seconds and SW 5 ft at 5 seconds, becoming
SW 9 ft at 7 seconds and S 4 ft at 9 seconds.
.SUN...W winds 20 to 25 kt with gusts up to 35 kt. Seas 7 to
10 ft. Wave Detail: SW 9 ft at 8 seconds and SE 6 ft at
9 seconds.
.SUN NIGHT...NW winds 25 to 30 kt. Seas 7 to 10 ft. Wave Detail:
W 8 ft at 7 seconds and SE 2 ft at 11 seconds.
.MON...NW winds 25 to 30 kt, diminishing to around 20 kt in the
afternoon. Seas 6 to 9 ft, subsiding to 4 to 6 ft in the
afternoon. Wave Detail: NW 7 ft at 7 seconds and E 2 ft at
10 seconds, becoming W 6 ft at 6 seconds and E 1 foot at
10 seconds.
.MON NIGHT...NW winds 15 to 20 kt, becoming W 10 to 15 kt after
midnight. Seas 3 to 4 ft. Wave Detail: W 4 ft at 6 seconds and E
1 foot at 9 seconds.
.TUE...SW winds 20 to 25 kt with gusts up to 30 kt. Seas 5 to
8 ft. Rain.
.TUE NIGHT...W winds 25 to 30 kt with gusts up to 35 kt. Seas
8 to 11 ft. A chance of rain.
.WED...NW winds 25 to 30 kt with gusts up to 35 kt. Seas 6 to
9 ft.
.WED NIGHT...NW winds 10 to 15 kt with gusts up to 20 kt. Seas
3 to 5 ft.
Seas are reported as significant wave height, which is the
average of the highest third of the waves. Individual wave
heights may be more than twice the significant wave height.
$$
ANZ256-210100-
Coastal Waters from Montauk NY to Marthas Vineyard extending out
to 20 nm South of Block Island-
704 AM EST Sat Dec 20 2025
...SMALL CRAFT ADVISORY IN EFFECT THROUGH LATE TONIGHT...
...GALE WATCH IN EFFECT FROM LATE TONIGHT THROUGH SUNDAY
MORNING...
.TODAY...NW winds 20 to 25 kt with gusts up to 30 kt, becoming W
10 to 15 kt this afternoon. Seas 9 to 12 ft, subsiding to 5 to
8 ft this afternoon. Wave Detail: S 11 ft at 11 seconds and NW
6 ft at 6 seconds, becoming S 8 ft at 11 seconds and W 2 ft at
5 seconds.
.TONIGHT...SW 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 5 to 7 ft, building to 7 to 10 ft after midnight. Wave
Detail: S 6 ft at 10 seconds and SW 5 ft at 5 seconds, becoming
SW 9 ft at 7 seconds and SE 4 ft at 10 seconds.
.SUN...W winds 25 to 30 kt, diminishing to 20 to 25 kt in the
afternoon. Seas 7 to 10 ft. Wave Detail: SW 9 ft at 8 seconds and
SE 5 ft at 10 seconds.
.SUN NIGHT...NW winds 25 to 30 kt. Seas 6 to 9 ft. Wave Detail:
NW 7 ft at 7 seconds and SE 2 ft at 10 seconds.
.MON...NW winds 20 to 25 kt, diminishing to 15 to 20 kt in the
afternoon. Gusts up to 30 kt. Seas 5 to 7 ft, subsiding to 3 to
5 ft in the afternoon. Wave Detail: NW 6 ft at 6 seconds and SE
2 ft at 10 seconds, becoming NW 5 ft at 5 seconds and SE 2 ft at
10 seconds.
.MON NIGHT...W winds 15 to 20 kt, diminishing to 10 to 15 kt
after midnight. Seas 2 to 4 ft. Wave Detail: W 4 ft at 5 seconds
and SE 1 foot at 9 seconds.
.TUE...SW winds 25 to 30 kt. Seas 5 to 8 ft. Rain.
.TUE NIGHT...W winds 25 to 30 kt with gusts up to 35 kt. Seas
7 to 10 ft. A chance of rain.
.WED...NW winds 25 to 30 kt. Seas 5 to 7 ft.
.WED NIGHT...NW winds 10 to 15 kt with gusts up 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.
$$
ANZ232-210100-
Nantucket Sound-
704 AM EST Sat Dec 20 2025
...SMALL CRAFT ADVISORY IN EFFECT THROUGH SUNDAY MORNING...
.TODAY...W winds 20 to 25 kt with gusts up to 30 kt, diminishing
to 10 to 15 kt this afternoon. Seas 4 to 6 ft. Wave Detail: W
5 ft at 5 seconds and S 3 ft at 11 seconds.
.TONIGHT...SW winds 15 to 20 kt, increasing to 20 to 25 kt after
midnight. Gusts up to 30 kt. Seas 2 to 4 ft, building to 4 to
6 ft after midnight. Wave Detail: SW 3 ft at 4 seconds and S 2 ft
at 11 seconds, becoming SW 4 ft at 5 seconds and S 2 ft at
10 seconds.
.SUN...SW winds 20 to 25 kt, becoming W 15 to 20 kt in the
afternoon. Gusts up to 30 kt. Seas 4 to 6 ft. Wave Detail: SW
4 ft at 5 seconds and SE 2 ft at 10 seconds.
.SUN NIGHT...NW winds 20 to 25 kt with gusts up to 30 kt. Seas
4 to 6 ft. Wave Detail: W 4 ft at 5 seconds and SE 1 foot at
10 seconds.
.MON...NW winds 20 to 25 kt, diminishing to 15 to 20 kt in the
afternoon. Seas 3 to 5 ft. Wave Detail: NW 4 ft at 4 seconds and
E 1 foot at 10 seconds.
.MON NIGHT...W winds 10 to 15 kt. Gusts up to 20 kt in the
evening. Seas 2 to 3 ft. Wave Detail: W 2 ft at 4 seconds and E
1 foot at 10 seconds.
.TUE...SW winds 15 to 20 kt with gusts up to 25 kt. Seas 2 to
4 ft. Rain.
.TUE NIGHT...W winds 20 to 25 kt. Seas 4 to 6 ft. A chance of
rain.
.WED...NW winds 20 to 25 kt. Seas 3 to 5 ft.
.WED NIGHT...NW winds 10 to 15 kt. Seas 2 to 3 ft.
Seas are reported as significant wave height, which is the
average of the highest third of the waves. Individual wave
heights may be more than twice the significant wave height.
$$
ANZ233-210100-
Vineyard Sound-
704 AM EST Sat Dec 20 2025
...SMALL CRAFT ADVISORY IN EFFECT THROUGH SUNDAY MORNING...
.TODAY...W winds 20 to 25 kt with gusts up to 30 kt, diminishing
to 10 to 15 kt this afternoon. Seas 5 to 8 ft, subsiding to 4 to
6 ft this afternoon. Wave Detail: SW 7 ft at 11 seconds and W
3 ft at 6 seconds, becoming S 5 ft at 11 seconds and W 2 ft at
6 seconds.
.TONIGHT...SW winds 15 to 20 kt, increasing to 25 to 30 kt after
midnight. Seas 3 to 5 ft, building to 5 to 7 ft after midnight.
Wave Detail: SW 4 ft at 5 seconds and S 3 ft at 10 seconds,
becoming SW 6 ft at 6 seconds and S 2 ft at 10 seconds.
.SUN...W winds 20 to 25 kt with gusts up to 30 kt. Seas 5 to
7 ft. Wave Detail: SW 6 ft at 7 seconds and S 3 ft at 10 seconds.
.SUN NIGHT...NW winds 20 to 25 kt with gusts up to 30 kt. Seas
4 to 6 ft. Wave Detail: W 4 ft at 7 seconds and SE 1 foot at
11 seconds.
.MON...NW winds 20 to 25 kt, diminishing to around 15 kt in the
afternoon. Seas 3 to 5 ft, subsiding to 2 to 3 ft in the
afternoon. Wave Detail: NW 4 ft at 6 seconds and SE 1 foot at
10 seconds, becoming W 3 ft at 5 seconds and E 1 foot at
9 seconds.
.MON NIGHT...W winds 10 to 15 kt. Gusts up to 20 kt in the
evening. Seas around 2 ft. Wave Detail: W 2 ft at 4 seconds and E
1 foot at 9 seconds.
.TUE...SW winds 20 to 25 kt. Seas 4 to 6 ft. Rain likely.
.TUE NIGHT...W winds 20 to 25 kt. Seas 5 to 7 ft. A chance of
rain.
.WED...NW winds 20 to 25 kt. Seas 3 to 5 ft.
.WED NIGHT...NW winds 10 to 15 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.
$$
ANZ234-210100-
Buzzards Bay-
704 AM EST Sat Dec 20 2025
...SMALL CRAFT ADVISORY IN EFFECT THROUGH SUNDAY MORNING...
.TODAY...W winds 15 to 20 kt with gusts up to 30 kt, diminishing
to around 10 kt this afternoon. Seas 4 to 6 ft, subsiding to 2 to
4 ft this afternoon. Wave Detail: SW 5 ft at 11 seconds and W
4 ft at 6 seconds, becoming S 4 ft at 11 seconds and W 2 ft at
6 seconds.
.TONIGHT...SW winds 15 to 20 kt, increasing to 20 to 25 kt after
midnight. Gusts up to 30 kt. Seas 2 to 4 ft, building to 4 to
6 ft after midnight. Wave Detail: SW 4 ft at 5 seconds and S 3 ft
at 10 seconds, becoming SW 6 ft at 6 seconds and S 1 foot at
10 seconds.
.SUN...SW winds 20 to 25 kt, becoming W 15 to 20 kt in the
afternoon. Gusts up to 30 kt. Seas 4 to 6 ft. Wave Detail: SW
5 ft at 7 seconds and S 2 ft at 9 seconds.
.SUN NIGHT...NW winds 20 to 25 kt with gusts up to 30 kt. Seas
3 to 5 ft. Wave Detail: W 4 ft at 6 seconds and SE 1 foot at
10 seconds.
.MON AND MON NIGHT...W winds 15 to 20 kt with gusts up to 25 kt.
Seas 2 to 3 ft. Wave Detail: NW 3 ft at 5 seconds and SE 1 foot
at 10 seconds.
.TUE...SW winds 20 to 25 kt. Seas 2 to 4 ft. Wave Detail: SW 4 ft
at 6 seconds and E 1 foot at 9 seconds. Rain with a chance of
snow.
.TUE NIGHT...W winds 15 to 20 kt with gusts up to 25 kt. Seas
3 to 5 ft. A chance of rain.
.WED...NW winds 15 to 20 kt with gusts up to 25 kt. Seas 2 to
4 ft.
.WED NIGHT...NW winds 5 to 10 kt. Seas around 2 ft.
Seas are reported as significant wave height, which is the
average of the highest third of the waves. Individual wave
heights may be more than twice the significant wave height.
$$
ANZ235-210100-
Rhode Island Sound-
704 AM EST Sat Dec 20 2025
...SMALL CRAFT ADVISORY IN EFFECT THROUGH LATE TONIGHT...
...GALE WATCH IN EFFECT FROM LATE TONIGHT THROUGH SUNDAY
MORNING...
.TODAY...W winds 20 to 25 kt with gusts up to 30 kt, diminishing
to 10 to 15 kt this afternoon. Seas 6 to 9 ft, subsiding to 5 to
7 ft this afternoon. Wave Detail: S 9 ft at 11 seconds and W 4 ft
at 6 seconds, becoming S 7 ft at 11 seconds and W 2 ft at
5 seconds.
.TONIGHT...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, building to
5 to 8 ft after midnight. Wave Detail: SW 5 ft at 5 seconds and S
5 ft at 10 seconds, becoming SW 8 ft at 7 seconds and S 4 ft at
10 seconds.
.SUN...W winds 20 to 25 kt with gusts up to 35 kt. Seas 5 to
8 ft. Wave Detail: SW 8 ft at 8 seconds and S 6 ft at 9 seconds.
.SUN NIGHT...NW winds 20 to 25 kt with gusts up to 30 kt. Seas
5 to 7 ft. Wave Detail: W 6 ft at 7 seconds and SE 2 ft at
11 seconds.
.MON...NW winds 20 to 25 kt, diminishing to around 15 kt in the
afternoon. Seas 3 to 5 ft. Wave Detail: NW 5 ft at 5 seconds and
SE 2 ft at 10 seconds.
.MON NIGHT...W winds 10 to 15 kt. Gusts up to 20 kt in the
evening. Seas 2 to 3 ft. Wave Detail: W 3 ft at 4 seconds and SE
1 foot at 9 seconds.
.TUE...SW winds 20 to 25 kt with gusts up to 30 kt. Seas 4 to
6 ft. Rain.
.TUE NIGHT...W winds 20 to 25 kt with gusts up to 30 kt. Seas
5 to 7 ft. A chance of rain.
.WED...NW winds 20 to 25 kt. Seas 3 to 5 ft.
.WED NIGHT...NW winds 10 to 15 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.
$$
ANZ237-210100-
Block Island Sound-
704 AM EST Sat Dec 20 2025
...SMALL CRAFT ADVISORY IN EFFECT THROUGH LATE TONIGHT...
...GALE WATCH IN EFFECT FROM LATE TONIGHT THROUGH SUNDAY
MORNING...
.TODAY...NW winds 15 to 20 kt with gusts up to 30 kt, becoming W
10 to 15 kt this afternoon. Seas 6 to 9 ft, subsiding to 4 to
6 ft this afternoon. Wave Detail: S 8 ft at 11 seconds and W 4 ft
at 5 seconds, becoming S 6 ft at 11 seconds and W 2 ft at
4 seconds.
.TONIGHT...SW winds 15 to 20 kt with gusts up to 25 kt,
increasing to 20 to 25 kt with gusts up to 35 kt after midnight.
Seas 3 to 5 ft, building to 5 to 7 ft after midnight. Wave
Detail: SW 4 ft at 4 seconds and S 4 ft at 10 seconds, becoming
SW 5 ft at 6 seconds and S 4 ft at 10 seconds.
.SUN...W winds 20 to 25 kt with gusts up to 30 kt. Seas 5 to
7 ft. Wave Detail: W 5 ft at 5 seconds and S 5 ft at 9 seconds.
.SUN NIGHT...NW winds 20 to 25 kt with gusts up to 30 kt. Seas
4 to 6 ft. Wave Detail: W 5 ft at 5 seconds and SE 3 ft at
10 seconds.
.MON...NW winds 15 to 20 kt, diminishing to 10 to 15 kt in the
afternoon. Gusts up to 25 kt. Seas 3 to 5 ft, subsiding to 2 to
3 ft in the afternoon. Wave Detail: NW 4 ft at 5 seconds and SE
2 ft at 10 seconds, becoming W 3 ft at 4 seconds and SE 2 ft at
10 seconds.
.MON NIGHT...W winds 10 to 15 kt. Gusts up to 20 kt in the
evening. Seas around 2 ft. Wave Detail: W 2 ft at 4 seconds and
SE 1 foot at 10 seconds.
.TUE...SW winds 15 to 20 kt with gusts up to 30 kt. Seas 3 to
5 ft. Rain.
.TUE NIGHT...W winds around 20 kt with gusts up to 30 kt. Seas
4 to 6 ft.
.WED...NW winds 15 to 20 kt with gusts up to 25 kt. Seas 3 to
5 ft.
.WED NIGHT...NW winds 5 to 10 kt. Seas 2 to 3 ft.
Seas are reported as significant wave height, which is the
average of the highest third of the waves. Individual wave
heights may be more than twice the significant wave height.
$$
ANZ230-210100-
Boston Harbor-
704 AM EST Sat Dec 20 2025
...SMALL CRAFT ADVISORY IN EFFECT UNTIL 10 AM EST THIS MORNING...
.TODAY...W winds 20 to 25 kt with gusts up to 30 kt, becoming SW
10 to 15 kt this afternoon. Waves around 2 ft.
.TONIGHT...SW winds 15 to 20 kt with gusts up to 30 kt. Waves
around 2 ft.
.SUN...W winds 15 to 20 kt with gusts up to 25 kt. Waves around
2 ft.
.SUN NIGHT...NW winds 15 to 20 kt with gusts up to 25 kt. Waves
around 2 ft.
.MON AND MON NIGHT...W winds 15 to 20 kt with gusts up to 25 kt.
Waves around 2 ft.
.TUE...S winds 10 to 15 kt with gusts up to 20 kt. Waves around
2 ft. Snow with rain likely.
.TUE NIGHT...W winds 15 to 20 kt with gusts up to 25 kt. Waves
around 2 ft. A chance of rain.
.WED AND WED NIGHT...NW winds 15 to 20 kt with gusts up to 25 kt,
becoming W 10 to 15 kt. Waves around 2 ft, then 1 foot or less.
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.
$$
ANZ236-210100-
Narragansett Bay-
704 AM EST Sat Dec 20 2025
...SMALL CRAFT ADVISORY IN EFFECT UNTIL 10 AM EST THIS MORNING...
.TODAY...W winds 15 to 20 kt with gusts up to 30 kt, diminishing
to 5 to 10 kt this afternoon. Waves 2 to 4 ft, except 4 to 6 ft
at the bay entrance.
.TONIGHT...SW winds 15 to 20 kt, increasing to 20 to 25 kt after
midnight. Gusts up to 30 kt. Waves 3 to 5 ft.
.SUN...W winds 15 to 20 kt with gusts up to 30 kt. Waves 3 to
5 ft.
.SUN NIGHT...NW winds 15 to 20 kt with gusts up to 25 kt. Waves
2 to 3 ft.
.MON AND MON NIGHT...W winds 10 to 15 kt with gusts up to 25 kt.
Waves 2 to 3 ft.
.TUE...SW winds 15 to 20 kt with gusts up to 25 kt. Waves 2 to
4 ft. Rain with a chance of snow.
.TUE NIGHT AND WED...NW winds 15 to 20 kt with gusts up to 25 kt.
Waves 2 to 4 ft.
.WED NIGHT...W winds 5 to 10 kt. Waves around 2 ft.
Seas are reported as significant wave height, which is the
average of the highest third of the waves. Individual wave
heights may be more than twice the significant wave height.
$$
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CWFBOX
Coastal Waters Forecast for Massachusetts and Rhode Island
National Weather Service Boston/Norton MA
704 AM EST Sat Dec 20 2025
Coastal waters from the Merrimack River MA to Watch Hill RI out
to 25 NM
ANZ200-210100-
704 AM EST Sat Dec 20 2025
.Synopsis for Massachusetts and Rhode Island coastal waters...
High pres builds over the waters this afternoon before moving
offshore tonight. Another cold front approaches tonight and moves
across the waters Sun afternoon. A period of pre-frontal SW gales is
possible tonight into Sun morning with continued gusty W-NW winds
late Sun into Sun night. High pres builds S of the waters late Mon
into Mon night, then a warm front moves into the waters Tue. Low
pres develops on the front east of New Eng Tue night and moves
offshore, then high pres builds in from the west Wed.
$$
ANZ250-210100-
Coastal waters east of Ipswich Bay and the Stellwagen Bank
National Marine Sanctuary-
704 AM EST Sat Dec 20 2025
...GALE WARNING IN EFFECT UNTIL 9 AM EST THIS MORNING...
.TODAY...W winds 25 to 30 kt with gusts up to 35 kt, diminishing
to 10 to 15 kt with gusts up to 20 kt this afternoon. Seas 7 to
10 ft, subsiding to 5 to 7 ft this afternoon. Wave Detail: W 8 ft
at 6 seconds and SE 6 ft at 11 seconds, becoming W 5 ft at
6 seconds and SE 5 ft at 11 seconds.
.TONIGHT...SW winds 20 to 25 kt, increasing to 25 to 30 kt after
midnight. Seas 4 to 6 ft. Wave Detail: SW 6 ft at 5 seconds and
SE 4 ft at 11 seconds.
.SUN...W winds 20 to 25 kt with gusts up to 30 kt. Seas 5 to
7 ft. Wave Detail: SW 6 ft at 5 seconds and SE 3 ft at
10 seconds.
.SUN NIGHT...NW winds 20 to 25 kt with gusts up to 30 kt. Seas
5 to 8 ft. Wave Detail: NW 6 ft at 5 seconds and SE 3 ft at
10 seconds.
.MON...NW winds 20 to 25 kt, diminishing to 15 to 20 kt in the
afternoon. Gusts up to 30 kt. Seas 5 to 8 ft, subsiding to 4 to
6 ft in the afternoon. Wave Detail: NW 6 ft at 6 seconds and E
2 ft at 10 seconds, becoming NW 5 ft at 5 seconds and E 2 ft at
10 seconds.
.MON NIGHT...W winds 10 to 15 kt with gusts up to 20 kt. Seas
2 to 4 ft. Wave Detail: W 4 ft at 5 seconds and E 2 ft at
10 seconds.
.TUE...SW winds 15 to 20 kt with gusts up to 25 kt. Seas 2 to
4 ft. Rain with a chance of snow.
.TUE NIGHT...W winds 20 to 25 kt with gusts up to 30 kt. Seas
3 to 5 ft. A chance of rain.
.WED...NW winds 20 to 25 kt with gusts up to 30 kt. Seas 4 to
6 ft.
.WED NIGHT...NW winds 10 to 15 kt with gusts up to 20 kt. Seas
3 to 5 ft.
Seas are reported as significant wave height, which is the
average of the highest third of the waves. Individual wave
heights may be more than twice the significant wave height.
$$
ANZ251-210100-
Massachusetts Bay and Ipswich Bay-
704 AM EST Sat Dec 20 2025
...SMALL CRAFT ADVISORY IN EFFECT THROUGH SUNDAY MORNING...
.TODAY...W winds 20 to 25 kt with gusts up to 35 kt, diminishing
to 10 to 15 kt this afternoon. Seas 4 to 6 ft. Wave Detail: W
5 ft at 5 seconds and SE 4 ft at 12 seconds.
.TONIGHT...SW winds 20 to 25 kt with gusts up to 35 kt. Seas 2 to
4 ft. Wave Detail: SW 4 ft at 4 seconds and E 3 ft at 11 seconds.
.SUN...SW winds 15 to 20 kt, becoming W 20 to 25 kt in the
afternoon. Gusts up to 30 kt. Seas 3 to 4 ft. Wave Detail: SW
4 ft at 4 seconds and E 2 ft at 10 seconds.
.SUN NIGHT...NW winds 20 to 25 kt with gusts up to 30 kt. Seas
3 to 5 ft. Wave Detail: NW 4 ft at 4 seconds and E 2 ft at
10 seconds.
.MON...NW winds 20 to 25 kt, diminishing to 15 to 20 kt in the
afternoon. Seas 3 to 5 ft. Wave Detail: NW 4 ft at 4 seconds and
E 2 ft at 10 seconds.
.MON NIGHT...W winds 10 to 15 kt. Gusts up to 20 kt in the
evening. Seas 2 to 3 ft. Wave Detail: NW 3 ft at 4 seconds and NE
2 ft at 8 seconds.
.TUE...SW winds 15 to 20 kt with gusts up to 25 kt. Seas 2 to
3 ft. Snow with rain likely.
.TUE NIGHT...W winds 20 to 25 kt. Seas 2 to 3 ft. A chance of
rain.
.WED AND WED NIGHT...NW winds 20 to 25 kt, becoming W 10 to
15 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.
$$
ANZ231-210100-
Cape Cod Bay-
704 AM EST Sat Dec 20 2025
...SMALL CRAFT ADVISORY IN EFFECT THROUGH SUNDAY MORNING...
.TODAY...W winds 20 to 25 kt with gusts up to 30 kt, diminishing
to 10 to 15 kt this afternoon. Seas 3 to 5 ft. Wave Detail: NW
4 ft at 6 seconds and SE 3 ft at 11 seconds.
.TONIGHT...SW winds 15 to 20 kt, increasing to 20 to 25 kt after
midnight. Gusts up to 30 kt. Seas 2 to 4 ft. Wave Detail: SW 3 ft
at 4 seconds and SE 1 foot at 9 seconds.
.SUN...W winds 15 to 20 kt with gusts up to 30 kt. Seas 3 to
4 ft. Wave Detail: SW 3 ft at 4 seconds and SE 2 ft at 8 seconds.
.SUN NIGHT...NW winds 20 to 25 kt with gusts up to 30 kt. Seas
3 to 5 ft. Wave Detail: NW 5 ft at 5 seconds and SE 2 ft at
10 seconds.
.MON...NW winds 20 to 25 kt, diminishing to 15 to 20 kt in the
afternoon. Gusts up to 30 kt. Seas 3 to 5 ft. Wave Detail: NW
5 ft at 6 seconds and E 1 foot at 10 seconds.
.MON NIGHT...W winds 10 to 15 kt. Gusts up to 20 kt in the
evening. Seas 2 to 3 ft. Wave Detail: NW 3 ft at 6 seconds and NE
1 foot at 9 seconds.
.TUE...SW winds 15 to 20 kt with gusts up to 25 kt. Seas 2 to
4 ft. Rain.
.TUE NIGHT...W winds 20 to 25 kt. Seas 2 to 3 ft. A chance of
rain.
.WED AND WED NIGHT...NW winds 20 to 25 kt with gusts up to 30 kt,
diminishing to 10 to 15 kt with gusts up to 20 kt. Seas 2 to
4 ft.
Seas are reported as significant wave height, which is the
average of the highest third of the waves. Individual wave
heights may be more than twice the significant wave height.
$$
ANZ254-210100-
Coastal waters from Provincetown MA to Chatham MA to Nantucket MA
out 20 nm-
704 AM EST Sat Dec 20 2025
...GALE WARNING IN EFFECT UNTIL 9 AM EST THIS MORNING...
.TODAY...NW winds 25 to 30 kt with gusts up to 35 kt, becoming W
10 to 15 kt with gusts up to 20 kt this afternoon. Seas 8 to
11 ft, subsiding to 5 to 8 ft this afternoon. Wave Detail: S 8 ft
at 11 seconds and NW 7 ft at 6 seconds, becoming S 7 ft at
11 seconds and NW 5 ft at 6 seconds.
.TONIGHT...SW 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 5 to 7 ft. Wave Detail: SW 6 ft at 6 seconds and S 5 ft at
10 seconds.
.SUN...SW winds 20 to 25 kt, becoming W 15 to 20 kt in the
afternoon. Gusts up to 30 kt. Seas 5 to 7 ft. Wave Detail: SW
6 ft at 6 seconds and SE 4 ft at 9 seconds.
.SUN NIGHT...NW winds 20 to 25 kt with gusts up to 30 kt. Seas
5 to 8 ft. Wave Detail: NW 7 ft at 6 seconds and SE 4 ft at
10 seconds.
.MON...NW winds 20 to 25 kt, diminishing to 15 to 20 kt in the
afternoon. Gusts up to 30 kt. Seas 5 to 8 ft. Wave Detail: NW
7 ft at 7 seconds and E 2 ft at 10 seconds.
.MON NIGHT...NW winds 15 to 20 kt, becoming W 10 to 15 kt after
midnight. Seas 3 to 5 ft. Wave Detail: NW 5 ft at 6 seconds and E
2 ft at 9 seconds.
.TUE...SW winds 15 to 20 kt with gusts up to 25 kt. Seas 3 to
5 ft. Rain.
.TUE NIGHT...W winds 20 to 25 kt with gusts up to 30 kt. Seas
5 to 7 ft, except 8 to 11 ft S and E of Nantucket. A chance of
rain.
.WED...NW winds 20 to 25 kt with gusts up to 30 kt. Seas 5 to
7 ft.
.WED NIGHT...NW winds 10 to 15 kt with gusts up to 20 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.
$$
ANZ255-210100-
Coastal Waters extending out to 25 nm South of Marthas Vineyard
and Nantucket-
704 AM EST Sat Dec 20 2025
...SMALL CRAFT ADVISORY IN EFFECT THROUGH SUNDAY MORNING...
.TODAY...NW winds 20 to 25 kt with gusts up to 30 kt, becoming W
10 to 15 kt this afternoon. Seas 9 to 13 ft, subsiding to 6 to
9 ft this afternoon. Wave Detail: SW 12 ft at 11 seconds and W
7 ft at 7 seconds, becoming SW 8 ft at 11 seconds and NW 2 ft at
6 seconds.
.TONIGHT...SW winds 15 to 20 kt with gusts up to 25 kt,
increasing to 25 to 30 kt with gusts up to 35 kt after midnight.
Seas 4 to 6 ft, building to 6 to 9 ft after midnight. Wave
Detail: SW 6 ft at 10 seconds and SW 5 ft at 5 seconds, becoming
SW 9 ft at 7 seconds and S 4 ft at 9 seconds.
.SUN...W winds 20 to 25 kt with gusts up to 35 kt. Seas 7 to
10 ft. Wave Detail: SW 9 ft at 8 seconds and SE 6 ft at
9 seconds.
.SUN NIGHT...NW winds 25 to 30 kt. Seas 7 to 10 ft. Wave Detail:
W 8 ft at 7 seconds and SE 2 ft at 11 seconds.
.MON...NW winds 25 to 30 kt, diminishing to around 20 kt in the
afternoon. Seas 6 to 9 ft, subsiding to 4 to 6 ft in the
afternoon. Wave Detail: NW 7 ft at 7 seconds and E 2 ft at
10 seconds, becoming W 6 ft at 6 seconds and E 1 foot at
10 seconds.
.MON NIGHT...NW winds 15 to 20 kt, becoming W 10 to 15 kt after
midnight. Seas 3 to 4 ft. Wave Detail: W 4 ft at 6 seconds and E
1 foot at 9 seconds.
.TUE...SW winds 20 to 25 kt with gusts up to 30 kt. Seas 5 to
8 ft. Rain.
.TUE NIGHT...W winds 25 to 30 kt with gusts up to 35 kt. Seas
8 to 11 ft. A chance of rain.
.WED...NW winds 25 to 30 kt with gusts up to 35 kt. Seas 6 to
9 ft.
.WED NIGHT...NW winds 10 to 15 kt with gusts up to 20 kt. Seas
3 to 5 ft.
Seas are reported as significant wave height, which is the
average of the highest third of the waves. Individual wave
heights may be more than twice the significant wave height.
$$
ANZ256-210100-
Coastal Waters from Montauk NY to Marthas Vineyard extending out
to 20 nm South of Block Island-
704 AM EST Sat Dec 20 2025
...SMALL CRAFT ADVISORY IN EFFECT THROUGH LATE TONIGHT...
...GALE WATCH IN EFFECT FROM LATE TONIGHT THROUGH SUNDAY
MORNING...
.TODAY...NW winds 20 to 25 kt with gusts up to 30 kt, becoming W
10 to 15 kt this afternoon. Seas 9 to 12 ft, subsiding to 5 to
8 ft this afternoon. Wave Detail: S 11 ft at 11 seconds and NW
6 ft at 6 seconds, becoming S 8 ft at 11 seconds and W 2 ft at
5 seconds.
.TONIGHT...SW 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 5 to 7 ft, building to 7 to 10 ft after midnight. Wave
Detail: S 6 ft at 10 seconds and SW 5 ft at 5 seconds, becoming
SW 9 ft at 7 seconds and SE 4 ft at 10 seconds.
.SUN...W winds 25 to 30 kt, diminishing to 20 to 25 kt in the
afternoon. Seas 7 to 10 ft. Wave Detail: SW 9 ft at 8 seconds and
SE 5 ft at 10 seconds.
.SUN NIGHT...NW winds 25 to 30 kt. Seas 6 to 9 ft. Wave Detail:
NW 7 ft at 7 seconds and SE 2 ft at 10 seconds.
.MON...NW winds 20 to 25 kt, diminishing to 15 to 20 kt in the
afternoon. Gusts up to 30 kt. Seas 5 to 7 ft, subsiding to 3 to
5 ft in the afternoon. Wave Detail: NW 6 ft at 6 seconds and SE
2 ft at 10 seconds, becoming NW 5 ft at 5 seconds and SE 2 ft at
10 seconds.
.MON NIGHT...W winds 15 to 20 kt, diminishing to 10 to 15 kt
after midnight. Seas 2 to 4 ft. Wave Detail: W 4 ft at 5 seconds
and SE 1 foot at 9 seconds.
.TUE...SW winds 25 to 30 kt. Seas 5 to 8 ft. Rain.
.TUE NIGHT...W winds 25 to 30 kt with gusts up to 35 kt. Seas
7 to 10 ft. A chance of rain.
.WED...NW winds 25 to 30 kt. Seas 5 to 7 ft.
.WED NIGHT...NW winds 10 to 15 kt with gusts up 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.
$$
ANZ232-210100-
Nantucket Sound-
704 AM EST Sat Dec 20 2025
...SMALL CRAFT ADVISORY IN EFFECT THROUGH SUNDAY MORNING...
.TODAY...W winds 20 to 25 kt with gusts up to 30 kt, diminishing
to 10 to 15 kt this afternoon. Seas 4 to 6 ft. Wave Detail: W
5 ft at 5 seconds and S 3 ft at 11 seconds.
.TONIGHT...SW winds 15 to 20 kt, increasing to 20 to 25 kt after
midnight. Gusts up to 30 kt. Seas 2 to 4 ft, building to 4 to
6 ft after midnight. Wave Detail: SW 3 ft at 4 seconds and S 2 ft
at 11 seconds, becoming SW 4 ft at 5 seconds and S 2 ft at
10 seconds.
.SUN...SW winds 20 to 25 kt, becoming W 15 to 20 kt in the
afternoon. Gusts up to 30 kt. Seas 4 to 6 ft. Wave Detail: SW
4 ft at 5 seconds and SE 2 ft at 10 seconds.
.SUN NIGHT...NW winds 20 to 25 kt with gusts up to 30 kt. Seas
4 to 6 ft. Wave Detail: W 4 ft at 5 seconds and SE 1 foot at
10 seconds.
.MON...NW winds 20 to 25 kt, diminishing to 15 to 20 kt in the
afternoon. Seas 3 to 5 ft. Wave Detail: NW 4 ft at 4 seconds and
E 1 foot at 10 seconds.
.MON NIGHT...W winds 10 to 15 kt. Gusts up to 20 kt in the
evening. Seas 2 to 3 ft. Wave Detail: W 2 ft at 4 seconds and E
1 foot at 10 seconds.
.TUE...SW winds 15 to 20 kt with gusts up to 25 kt. Seas 2 to
4 ft. Rain.
.TUE NIGHT...W winds 20 to 25 kt. Seas 4 to 6 ft. A chance of
rain.
.WED...NW winds 20 to 25 kt. Seas 3 to 5 ft.
.WED NIGHT...NW winds 10 to 15 kt. Seas 2 to 3 ft.
Seas are reported as significant wave height, which is the
average of the highest third of the waves. Individual wave
heights may be more than twice the significant wave height.
$$
ANZ233-210100-
Vineyard Sound-
704 AM EST Sat Dec 20 2025
...SMALL CRAFT ADVISORY IN EFFECT THROUGH SUNDAY MORNING...
.TODAY...W winds 20 to 25 kt with gusts up to 30 kt, diminishing
to 10 to 15 kt this afternoon. Seas 5 to 8 ft, subsiding to 4 to
6 ft this afternoon. Wave Detail: SW 7 ft at 11 seconds and W
3 ft at 6 seconds, becoming S 5 ft at 11 seconds and W 2 ft at
6 seconds.
.TONIGHT...SW winds 15 to 20 kt, increasing to 25 to 30 kt after
midnight. Seas 3 to 5 ft, building to 5 to 7 ft after midnight.
Wave Detail: SW 4 ft at 5 seconds and S 3 ft at 10 seconds,
becoming SW 6 ft at 6 seconds and S 2 ft at 10 seconds.
.SUN...W winds 20 to 25 kt with gusts up to 30 kt. Seas 5 to
7 ft. Wave Detail: SW 6 ft at 7 seconds and S 3 ft at 10 seconds.
.SUN NIGHT...NW winds 20 to 25 kt with gusts up to 30 kt. Seas
4 to 6 ft. Wave Detail: W 4 ft at 7 seconds and SE 1 foot at
11 seconds.
.MON...NW winds 20 to 25 kt, diminishing to around 15 kt in the
afternoon. Seas 3 to 5 ft, subsiding to 2 to 3 ft in the
afternoon. Wave Detail: NW 4 ft at 6 seconds and SE 1 foot at
10 seconds, becoming W 3 ft at 5 seconds and E 1 foot at
9 seconds.
.MON NIGHT...W winds 10 to 15 kt. Gusts up to 20 kt in the
evening. Seas around 2 ft. Wave Detail: W 2 ft at 4 seconds and E
1 foot at 9 seconds.
.TUE...SW winds 20 to 25 kt. Seas 4 to 6 ft. Rain likely.
.TUE NIGHT...W winds 20 to 25 kt. Seas 5 to 7 ft. A chance of
rain.
.WED...NW winds 20 to 25 kt. Seas 3 to 5 ft.
.WED NIGHT...NW winds 10 to 15 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.
$$
ANZ234-210100-
Buzzards Bay-
704 AM EST Sat Dec 20 2025
...SMALL CRAFT ADVISORY IN EFFECT THROUGH SUNDAY MORNING...
.TODAY...W winds 15 to 20 kt with gusts up to 30 kt, diminishing
to around 10 kt this afternoon. Seas 4 to 6 ft, subsiding to 2 to
4 ft this afternoon. Wave Detail: SW 5 ft at 11 seconds and W
4 ft at 6 seconds, becoming S 4 ft at 11 seconds and W 2 ft at
6 seconds.
.TONIGHT...SW winds 15 to 20 kt, increasing to 20 to 25 kt after
midnight. Gusts up to 30 kt. Seas 2 to 4 ft, building to 4 to
6 ft after midnight. Wave Detail: SW 4 ft at 5 seconds and S 3 ft
at 10 seconds, becoming SW 6 ft at 6 seconds and S 1 foot at
10 seconds.
.SUN...SW winds 20 to 25 kt, becoming W 15 to 20 kt in the
afternoon. Gusts up to 30 kt. Seas 4 to 6 ft. Wave Detail: SW
5 ft at 7 seconds and S 2 ft at 9 seconds.
.SUN NIGHT...NW winds 20 to 25 kt with gusts up to 30 kt. Seas
3 to 5 ft. Wave Detail: W 4 ft at 6 seconds and SE 1 foot at
10 seconds.
.MON AND MON NIGHT...W winds 15 to 20 kt with gusts up to 25 kt.
Seas 2 to 3 ft. Wave Detail: NW 3 ft at 5 seconds and SE 1 foot
at 10 seconds.
.TUE...SW winds 20 to 25 kt. Seas 2 to 4 ft. Wave Detail: SW 4 ft
at 6 seconds and E 1 foot at 9 seconds. Rain with a chance of
snow.
.TUE NIGHT...W winds 15 to 20 kt with gusts up to 25 kt. Seas
3 to 5 ft. A chance of rain.
.WED...NW winds 15 to 20 kt with gusts up to 25 kt. Seas 2 to
4 ft.
.WED NIGHT...NW winds 5 to 10 kt. Seas around 2 ft.
Seas are reported as significant wave height, which is the
average of the highest third of the waves. Individual wave
heights may be more than twice the significant wave height.
$$
ANZ235-210100-
Rhode Island Sound-
704 AM EST Sat Dec 20 2025
...SMALL CRAFT ADVISORY IN EFFECT THROUGH LATE TONIGHT...
...GALE WATCH IN EFFECT FROM LATE TONIGHT THROUGH SUNDAY
MORNING...
.TODAY...W winds 20 to 25 kt with gusts up to 30 kt, diminishing
to 10 to 15 kt this afternoon. Seas 6 to 9 ft, subsiding to 5 to
7 ft this afternoon. Wave Detail: S 9 ft at 11 seconds and W 4 ft
at 6 seconds, becoming S 7 ft at 11 seconds and W 2 ft at
5 seconds.
.TONIGHT...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, building to
5 to 8 ft after midnight. Wave Detail: SW 5 ft at 5 seconds and S
5 ft at 10 seconds, becoming SW 8 ft at 7 seconds and S 4 ft at
10 seconds.
.SUN...W winds 20 to 25 kt with gusts up to 35 kt. Seas 5 to
8 ft. Wave Detail: SW 8 ft at 8 seconds and S 6 ft at 9 seconds.
.SUN NIGHT...NW winds 20 to 25 kt with gusts up to 30 kt. Seas
5 to 7 ft. Wave Detail: W 6 ft at 7 seconds and SE 2 ft at
11 seconds.
.MON...NW winds 20 to 25 kt, diminishing to around 15 kt in the
afternoon. Seas 3 to 5 ft. Wave Detail: NW 5 ft at 5 seconds and
SE 2 ft at 10 seconds.
.MON NIGHT...W winds 10 to 15 kt. Gusts up to 20 kt in the
evening. Seas 2 to 3 ft. Wave Detail: W 3 ft at 4 seconds and SE
1 foot at 9 seconds.
.TUE...SW winds 20 to 25 kt with gusts up to 30 kt. Seas 4 to
6 ft. Rain.
.TUE NIGHT...W winds 20 to 25 kt with gusts up to 30 kt. Seas
5 to 7 ft. A chance of rain.
.WED...NW winds 20 to 25 kt. Seas 3 to 5 ft.
.WED NIGHT...NW winds 10 to 15 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.
$$
ANZ237-210100-
Block Island Sound-
704 AM EST Sat Dec 20 2025
...SMALL CRAFT ADVISORY IN EFFECT THROUGH LATE TONIGHT...
...GALE WATCH IN EFFECT FROM LATE TONIGHT THROUGH SUNDAY
MORNING...
.TODAY...NW winds 15 to 20 kt with gusts up to 30 kt, becoming W
10 to 15 kt this afternoon. Seas 6 to 9 ft, subsiding to 4 to
6 ft this afternoon. Wave Detail: S 8 ft at 11 seconds and W 4 ft
at 5 seconds, becoming S 6 ft at 11 seconds and W 2 ft at
4 seconds.
.TONIGHT...SW winds 15 to 20 kt with gusts up to 25 kt,
increasing to 20 to 25 kt with gusts up to 35 kt after midnight.
Seas 3 to 5 ft, building to 5 to 7 ft after midnight. Wave
Detail: SW 4 ft at 4 seconds and S 4 ft at 10 seconds, becoming
SW 5 ft at 6 seconds and S 4 ft at 10 seconds.
.SUN...W winds 20 to 25 kt with gusts up to 30 kt. Seas 5 to
7 ft. Wave Detail: W 5 ft at 5 seconds and S 5 ft at 9 seconds.
.SUN NIGHT...NW winds 20 to 25 kt with gusts up to 30 kt. Seas
4 to 6 ft. Wave Detail: W 5 ft at 5 seconds and SE 3 ft at
10 seconds.
.MON...NW winds 15 to 20 kt, diminishing to 10 to 15 kt in the
afternoon. Gusts up to 25 kt. Seas 3 to 5 ft, subsiding to 2 to
3 ft in the afternoon. Wave Detail: NW 4 ft at 5 seconds and SE
2 ft at 10 seconds, becoming W 3 ft at 4 seconds and SE 2 ft at
10 seconds.
.MON NIGHT...W winds 10 to 15 kt. Gusts up to 20 kt in the
evening. Seas around 2 ft. Wave Detail: W 2 ft at 4 seconds and
SE 1 foot at 10 seconds.
.TUE...SW winds 15 to 20 kt with gusts up to 30 kt. Seas 3 to
5 ft. Rain.
.TUE NIGHT...W winds around 20 kt with gusts up to 30 kt. Seas
4 to 6 ft.
.WED...NW winds 15 to 20 kt with gusts up to 25 kt. Seas 3 to
5 ft.
.WED NIGHT...NW winds 5 to 10 kt. Seas 2 to 3 ft.
Seas are reported as significant wave height, which is the
average of the highest third of the waves. Individual wave
heights may be more than twice the significant wave height.
$$
ANZ230-210100-
Boston Harbor-
704 AM EST Sat Dec 20 2025
...SMALL CRAFT ADVISORY IN EFFECT UNTIL 10 AM EST THIS MORNING...
.TODAY...W winds 20 to 25 kt with gusts up to 30 kt, becoming SW
10 to 15 kt this afternoon. Waves around 2 ft.
.TONIGHT...SW winds 15 to 20 kt with gusts up to 30 kt. Waves
around 2 ft.
.SUN...W winds 15 to 20 kt with gusts up to 25 kt. Waves around
2 ft.
.SUN NIGHT...NW winds 15 to 20 kt with gusts up to 25 kt. Waves
around 2 ft.
.MON AND MON NIGHT...W winds 15 to 20 kt with gusts up to 25 kt.
Waves around 2 ft.
.TUE...S winds 10 to 15 kt with gusts up to 20 kt. Waves around
2 ft. Snow with rain likely.
.TUE NIGHT...W winds 15 to 20 kt with gusts up to 25 kt. Waves
around 2 ft. A chance of rain.
.WED AND WED NIGHT...NW winds 15 to 20 kt with gusts up to 25 kt,
becoming W 10 to 15 kt. Waves around 2 ft, then 1 foot or less.
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.
$$
ANZ236-210100-
Narragansett Bay-
704 AM EST Sat Dec 20 2025
...SMALL CRAFT ADVISORY IN EFFECT UNTIL 10 AM EST THIS MORNING...
.TODAY...W winds 15 to 20 kt with gusts up to 30 kt, diminishing
to 5 to 10 kt this afternoon. Waves 2 to 4 ft, except 4 to 6 ft
at the bay entrance.
.TONIGHT...SW winds 15 to 20 kt, increasing to 20 to 25 kt after
midnight. Gusts up to 30 kt. Waves 3 to 5 ft.
.SUN...W winds 15 to 20 kt with gusts up to 30 kt. Waves 3 to
5 ft.
.SUN NIGHT...NW winds 15 to 20 kt with gusts up to 25 kt. Waves
2 to 3 ft.
.MON AND MON NIGHT...W winds 10 to 15 kt with gusts up to 25 kt.
Waves 2 to 3 ft.
.TUE...SW winds 15 to 20 kt with gusts up to 25 kt. Waves 2 to
4 ft. Rain with a chance of snow.
.TUE NIGHT AND WED...NW winds 15 to 20 kt with gusts up to 25 kt.
Waves 2 to 4 ft.
.WED NIGHT...W winds 5 to 10 kt. Waves around 2 ft.
Seas are reported as significant wave height, which is the
average of the highest third of the waves. Individual wave
heights may be more than twice the significant wave height.
$$
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