Coastal Waters Forecast
Issued by NWS Boston, MA
Issued by NWS Boston, MA
Versions:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
717 FZUS51 KBOX 220305 CWFBOX Coastal Waters Forecast for Massachusetts and Rhode Island National Weather Service Boston/Norton MA 1004 PM EST Fri Nov 21 2025 Coastal waters from the Merrimack River MA to Watch Hill RI out to 25 NM ANZ200-221600- 1004 PM EST Fri Nov 21 2025 .Synopsis for Massachusetts and Rhode Island coastal waters... High pressure moves south of the waters into tonight. Cold front moves through tonight which may bring showers to the southern waters. High pres returns late Saturday and remains through early next week. High pres moves offshore Tuesday. Rain possible late Tuesday into Thursday with a frontal system. $$ ANZ250-221600- Coastal waters east of Ipswich Bay and the Stellwagen Bank National Marine Sanctuary- 1004 PM EST Fri Nov 21 2025 .OVERNIGHT...W winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to 3 ft. Wave Detail: SW 3 ft at 5 seconds and E 2 ft at 7 seconds. .SAT...NW winds 10 to 15 kt. Gusts up to 20 kt in the afternoon. Seas 2 to 3 ft. Wave Detail: W 2 ft at 3 seconds and SE 2 ft at 7 seconds. .SAT NIGHT...NW winds 15 to 20 kt, diminishing to 10 to 15 kt after midnight. Gusts up to 25 kt. Seas 3 to 4 ft. Wave Detail: NW 3 ft at 4 seconds and E 2 ft at 7 seconds. .SUN...W winds around 10 kt. Seas 2 to 4 ft. Wave Detail: NW 2 ft at 4 seconds and E 1 foot at 7 seconds. .SUN NIGHT THROUGH MON NIGHT...W winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to 3 ft. Wave Detail: NW 3 ft at 4 seconds and E 1 foot at 7 seconds. .TUE...SW winds around 10 kt. Seas around 2 ft. Wave Detail: W 2 ft at 3 seconds and SE 1 foot at 3 seconds. A chance of rain. .TUE NIGHT AND WED...S winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to 3 ft. Rain likely. .WED NIGHT...W winds 15 to 20 kt with gusts up to 25 kt. Seas 2 to 4 ft. A chance of rain. Seas are reported as significant wave height, which is the average of the highest third of the waves. Individual wave heights may be more than twice the significant wave height. $$ ANZ251-221600- Massachusetts Bay and Ipswich Bay- 1004 PM EST Fri Nov 21 2025 .OVERNIGHT...W winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to 3 ft. Wave Detail: SW 2 ft at 4 seconds and E 1 foot at 7 seconds. .SAT...NW 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: SE 2 ft at 6 seconds and W 1 foot at 2 seconds. .SAT NIGHT...NW winds 10 to 15 kt with gusts up to 25 kt. Seas 2 to 3 ft. Wave Detail: NW 2 ft at 3 seconds and E 2 ft at 7 seconds. .SUN...W winds 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: NW 2 ft at 3 seconds and S 1 foot at 6 seconds. .SUN NIGHT THROUGH MON NIGHT...W winds 10 to 15 kt with gusts up to 20 kt. Seas around 2 ft. Wave Detail: W 2 ft at 3 seconds and SE 1 foot at 7 seconds. .TUE...SW winds 5 to 10 kt. Seas around 2 ft. Wave Detail: SE 1 foot at 3 seconds and W 1 foot at 3 seconds. A chance of rain. .TUE NIGHT AND WED...S winds around 10 kt. Seas around 2 ft. Rain likely. .WED NIGHT...W winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to 3 ft. A chance of rain. 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. $$ ANZ231-221600- Cape Cod Bay- 1004 PM EST Fri Nov 21 2025 .OVERNIGHT...W winds 10 to 15 kt, diminishing to 5 to 10 kt. Gusts up to 20 kt. Seas around 2 ft. Wave Detail: W 1 foot at 2 seconds and SE 1 foot at 6 seconds. Showers likely. .SAT...NW winds 5 to 10 kt, becoming N 10 to 15 kt with gusts up to 20 kt in the afternoon. Seas 2 to 3 ft. Wave Detail: NW 1 foot at 3 seconds and S 1 foot at 5 seconds. Showers in the morning with vsby 1 to 3 NM. .SAT NIGHT...NW winds 10 to 15 kt with gusts up to 25 kt. Seas 2 to 3 ft. Wave Detail: NW 2 ft at 4 seconds and S 1 foot at 4 seconds. .SUN...W winds 5 to 10 kt. Seas around 2 ft. Wave Detail: N 2 ft at 5 seconds and S 1 foot at 7 seconds. .SUN NIGHT THROUGH MON NIGHT...W winds 10 to 15 kt with gusts up to 20 kt. Seas around 2 ft. Wave Detail: W 2 ft at 3 seconds and NE 1 foot at 5 seconds. .TUE...SW winds 5 to 10 kt. Seas around 2 ft. Wave Detail: W 1 foot at 6 seconds and E 1 foot at 9 seconds. A chance of rain. .TUE NIGHT AND WED...S winds 10 to 15 kt. Gusts up to 20 kt. Seas around 2 ft. Rain likely. .WED NIGHT...W winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to 3 ft. A chance of rain. Seas are reported as significant wave height, which is the average of the highest third of the waves. Individual wave heights may be more than twice the significant wave height. $$ ANZ254-221600- Coastal waters from Provincetown MA to Chatham MA to Nantucket MA out 20 nm- 1004 PM EST Fri Nov 21 2025 .OVERNIGHT...SW winds 10 to 15 kt, becoming W 5 to 10 kt. Gusts up to 20 kt. Seas 2 to 3 ft. Wave Detail: SW 2 ft at 4 seconds and E 2 ft at 7 seconds. A chance of showers. .SAT...NW winds 5 to 10 kt, becoming N 10 to 15 kt with gusts up to 20 kt in the afternoon. Seas 2 to 4 ft. Wave Detail: NW 2 ft at 3 seconds and E 2 ft at 7 seconds. Showers, mainly in the morning with vsby 1 NM or less. .SAT NIGHT...NW winds 10 to 15 kt with gusts up to 25 kt. Seas 3 to 5 ft. Wave Detail: NW 3 ft at 4 seconds and E 2 ft at 7 seconds. .SUN...W winds 5 to 10 kt, becoming SW 10 to 15 kt in the afternoon. Seas 2 to 4 ft. Wave Detail: NW 2 ft at 5 seconds and NE 2 ft at 7 seconds. .SUN NIGHT THROUGH MON NIGHT...NW winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to 3 ft. Wave Detail: NW 3 ft at 4 seconds and NE 2 ft at 6 seconds. .TUE...SW winds 10 to 15 kt. Seas around 2 ft. Wave Detail: W 2 ft at 5 seconds and N 2 ft at 6 seconds. .TUE NIGHT AND WED...S winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to 4 ft. Rain likely. .WED NIGHT...SW winds 15 to 20 kt. Seas 3 to 5 ft. Rain likely. Seas are reported as significant wave height, which is the average of the highest third of the waves. Individual wave heights may be more than twice the significant wave height. $$ ANZ255-221600- Coastal Waters extending out to 25 nm South of Marthas Vineyard and Nantucket- 1004 PM EST Fri Nov 21 2025 .OVERNIGHT...W winds 10 to 15 kt, diminishing to 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: SW 3 ft at 5 seconds and E 2 ft at 6 seconds. A slight chance of showers. Showers. .SAT...N winds 5 to 10 kt, increasing to 10 to 15 kt with gusts up to 20 kt in the afternoon. Seas 2 to 4 ft. Wave Detail: SW 2 ft at 5 seconds and E 2 ft at 7 seconds. Showers, mainly in the morning with vsby 1 NM or less. .SAT NIGHT...N winds 10 to 15 kt with gusts up to 25 kt. Seas 3 to 5 ft. Wave Detail: NW 2 ft at 4 seconds and E 2 ft at 7 seconds. .SUN...NW winds 5 to 10 kt, becoming W 10 to 15 kt with gusts up to 20 kt in the afternoon. Seas 2 to 4 ft. Wave Detail: W 3 ft at 4 seconds and NE 2 ft at 6 seconds. .SUN NIGHT THROUGH MON NIGHT...NW winds 15 to 20 kt. Seas 2 to 4 ft. Wave Detail: W 4 ft at 6 seconds and E 1 foot at 7 seconds. .TUE...SW winds 10 to 15 kt. Seas around 2 ft. Wave Detail: SW 2 ft at 5 seconds and N 1 foot at 4 seconds. .TUE NIGHT AND WED...S winds 15 to 20 kt. Seas 3 to 5 ft. Rain likely. .WED NIGHT...W winds 20 to 25 kt. Seas 4 to 6 ft. Rain likely. Seas are reported as significant wave height, which is the average of the highest third of the waves. Individual wave heights may be more than twice the significant wave height. $$ ANZ256-221600- Coastal Waters from Montauk NY to Marthas Vineyard extending out to 20 nm South of Block Island- 1004 PM EST Fri Nov 21 2025 .OVERNIGHT...W winds 10 to 15 kt, diminishing to 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: SW 3 ft at 5 seconds and E 2 ft at 7 seconds. Showers. .SAT...N 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 2 ft at 4 seconds and E 2 ft at 7 seconds. Showers in the morning with vsby 1 to 3 NM. .SAT NIGHT...N winds 10 to 15 kt with gusts up to 25 kt. Seas 3 to 4 ft. Wave Detail: NW 3 ft at 4 seconds and E 2 ft at 7 seconds. .SUN...NW winds 5 to 10 kt, becoming W 10 to 15 kt with gusts up to 20 kt in the afternoon. Seas 2 to 4 ft. Wave Detail: W 3 ft at 4 seconds and S 2 ft at 7 seconds. .SUN NIGHT THROUGH MON NIGHT...W winds 15 to 20 kt with gusts up to 25 kt. Seas 2 to 4 ft. Wave Detail: W 3 ft at 4 seconds and SW 3 ft at 7 seconds. .TUE...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 N 1 foot at 3 seconds. A chance of rain. .TUE NIGHT AND WED...SW winds 15 to 20 kt with gusts up to 25 kt. Seas 3 to 5 ft. Rain. .WED NIGHT...W winds 20 to 25 kt. Seas 4 to 6 ft. A chance of rain. 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. $$ ANZ232-221600- Nantucket Sound- 1004 PM EST Fri Nov 21 2025 .OVERNIGHT...W winds 5 to 10 kt. Seas around 2 ft. Wave Detail: SW 1 foot at 4 seconds and E 1 foot at 6 seconds. Showers. .SAT...NW winds 5 to 10 kt, becoming N 10 to 15 kt with gusts up to 20 kt in the afternoon. Seas 2 to 3 ft. Wave Detail: SW 1 foot at 4 seconds and E 1 foot at 7 seconds. Showers, mainly in the morning with vsby 1 to 3 NM. .SAT NIGHT...NW winds 10 to 15 kt with gusts up to 25 kt. Seas 2 to 3 ft. Wave Detail: NW 2 ft at 3 seconds and E 1 foot at 7 seconds. .SUN...NW winds 5 to 10 kt, becoming SW 10 to 15 kt in the afternoon. Seas 2 to 3 ft. Wave Detail: W 2 ft at 3 seconds and NE 1 foot at 6 seconds. .SUN NIGHT THROUGH MON NIGHT...NW winds 10 to 15 kt with gusts up to 20 kt. Seas around 2 ft. Wave Detail: W 2 ft at 3 seconds and SW 2 ft at 6 seconds. .TUE...SW winds 10 to 15 kt. Seas around 2 ft. Wave Detail: SW 2 ft at 3 seconds and N 1 foot at 4 seconds. .TUE NIGHT AND WED...S winds 15 to 20 kt. Seas 2 to 3 ft. Rain likely. .WED NIGHT...W winds 15 to 20 kt. Seas 2 to 3 ft. A chance of rain. Seas are reported as significant wave height, which is the average of the highest third of the waves. Individual wave heights may be more than twice the significant wave height. $$ ANZ233-221600- Vineyard Sound- 1004 PM EST Fri Nov 21 2025 .OVERNIGHT...W winds 5 to 10 kt. Seas around 2 ft. Wave Detail: SW 2 ft at 5 seconds and E 1 foot at 6 seconds. Showers. .SAT...N winds 5 to 10 kt. Gusts up to 20 kt in the afternoon. Seas around 2 ft. Wave Detail: SW 1 foot at 5 seconds and E 1 foot at 6 seconds. Showers in the morning with vsby 1 to 3 NM. .SAT NIGHT...NW winds 10 to 15 kt, diminishing to 5 to 10 kt after midnight. Gusts up to 20 kt. Seas 2 to 3 ft. Wave Detail: NW 1 foot at 3 seconds and S 1 foot at 6 seconds. .SUN...NW winds 5 to 10 kt, becoming W 10 to 15 kt in the afternoon. Seas 2 to 3 ft. Wave Detail: SW 2 ft at 4 seconds and NE 1 foot at 6 seconds. .SUN NIGHT THROUGH MON NIGHT...W winds 10 to 15 kt with gusts up to 20 kt. Seas around 2 ft. Wave Detail: SW 2 ft at 4 seconds and SW 2 ft at 7 seconds. .TUE...SW winds 10 to 15 kt. Seas around 2 ft. Wave Detail: SW 2 ft at 5 seconds and N 1 foot at 4 seconds. A chance of rain. .TUE NIGHT AND WED...S winds 15 to 20 kt. Seas 2 to 3 ft. Rain likely. .WED NIGHT...W winds 15 to 20 kt. Seas 2 to 4 ft. A chance of rain. 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. $$ ANZ234-221600- Buzzards Bay- 1004 PM EST Fri Nov 21 2025 .OVERNIGHT...W winds 5 to 10 kt. Seas around 2 ft. Wave Detail: SW 2 ft at 5 seconds and E 1 foot at 6 seconds. Showers. .SAT...N winds 5 to 10 kt. Gusts up to 20 kt in the afternoon. Seas around 2 ft. Wave Detail: SW 1 foot at 5 seconds and E 1 foot at 6 seconds. Showers in the morning with vsby 1 to 3 NM. .SAT NIGHT...NW winds 5 to 10 kt. Gusts up to 20 kt in the evening. Seas 2 to 3 ft. Wave Detail: NW 1 foot at 2 seconds and S 1 foot at 4 seconds. .SUN...NW winds 5 to 10 kt, becoming SW 10 to 15 kt in the afternoon. Seas around 2 ft. Wave Detail: SW 2 ft at 3 seconds and NE 1 foot at 6 seconds. .SUN NIGHT THROUGH MON NIGHT...W winds 10 to 15 kt. Seas around 2 ft. Wave Detail: SW 2 ft at 4 seconds and SW 2 ft at 7 seconds. .TUE...SW winds 10 to 15 kt. Seas around 2 ft. Wave Detail: SW 2 ft at 5 seconds and N 1 foot at 4 seconds. A chance of rain. .TUE NIGHT AND WED...S winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to 3 ft. Rain likely. .WED NIGHT...W winds 15 to 20 kt. Seas 2 to 3 ft. A chance of rain. Seas are reported as significant wave height, which is the average of the highest third of the waves. Individual wave heights may be more than twice the significant wave height. $$ ANZ235-221600- Rhode Island Sound- 1004 PM EST Fri Nov 21 2025 .OVERNIGHT...W winds 10 to 15 kt, diminishing to 5 to 10 kt. Seas 2 to 3 ft. Wave Detail: SW 2 ft at 5 seconds and SE 1 foot at 6 seconds. Showers. .SAT...N 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 1 foot at 4 seconds and SE 1 foot at 6 seconds. Showers in the morning with vsby 1 to 3 NM. .SAT NIGHT...NW winds 10 to 15 kt with gusts up to 25 kt. Seas 2 to 3 ft. Wave Detail: NW 2 ft at 3 seconds and S 1 foot at 4 seconds. .SUN...NW winds 5 to 10 kt, becoming W 10 to 15 kt with gusts up to 20 kt in the afternoon. Seas 2 to 3 ft. Wave Detail: W 2 ft at 4 seconds and S 2 ft at 7 seconds. .SUN NIGHT THROUGH MON NIGHT...W winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to 3 ft. Wave Detail: S 3 ft at 7 seconds and W 2 ft at 4 seconds. .TUE...SW winds 10 to 15 kt. Seas around 2 ft. Wave Detail: SW 2 ft at 4 seconds and SE 1 foot at 9 seconds. A chance of rain. .TUE NIGHT AND WED...SW winds 15 to 20 kt. Seas 2 to 4 ft. Rain likely. .WED NIGHT...W winds 15 to 20 kt. Seas 3 to 5 ft. A chance of rain. 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. $$ ANZ237-221600- Block Island Sound- 1004 PM EST Fri Nov 21 2025 .OVERNIGHT...W winds 5 to 10 kt. Seas around 2 ft. Wave Detail: SW 2 ft at 4 seconds and SE 1 foot at 6 seconds. Showers. .SAT...N winds 5 to 10 kt. Gusts up to 20 kt in the afternoon. Seas 2 to 3 ft. Wave Detail: W 1 foot at 3 seconds and SE 1 foot at 6 seconds. Showers in the morning with vsby 1 to 3 NM. .SAT NIGHT...NW winds 10 to 15 kt, becoming N 5 to 10 kt after midnight. Gusts up to 25 kt. Seas 2 to 3 ft. Wave Detail: NW 1 foot at 3 seconds and SE 1 foot at 5 seconds. .SUN...NW winds 5 to 10 kt, becoming W 10 to 15 kt in the afternoon. Seas 2 to 3 ft. Wave Detail: W 2 ft at 3 seconds and S 2 ft at 7 seconds. .SUN NIGHT THROUGH MON NIGHT...W winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to 3 ft. Wave Detail: W 2 ft at 3 seconds and SE 2 ft at 8 seconds. .TUE...SW winds 10 to 15 kt with gusts up to 20 kt. Seas around 2 ft. Wave Detail: SW 2 ft at 3 seconds and SW 1 foot at 6 seconds. A chance of rain. .TUE NIGHT AND WED...SW winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to 4 ft. Rain likely. .WED NIGHT...W winds 15 to 20 kt. Seas 3 to 4 ft. A chance of rain. Seas are reported as significant wave height, which is the average of the highest third of the waves. Individual wave heights may be more than twice the significant wave height. $$ ANZ230-221600- Boston Harbor- 1004 PM EST Fri Nov 21 2025 .OVERNIGHT...W winds 5 to 10 kt. Gusts up to 20 kt. Waves around 2 ft. .SAT...NW winds 5 to 10 kt. Gusts up to 20 kt in the afternoon. Waves 1 foot or less, then around 2 ft in the afternoon. .SAT NIGHT...NW winds 5 to 10 kt with gusts up to 20 kt. Waves around 2 ft. .SUN...W winds 5 to 10 kt. Waves 1 foot or less. .SUN NIGHT THROUGH MON NIGHT...W winds 10 to 15 kt. Waves around 2 ft. .TUE...SW winds 5 to 10 kt. Waves around 2 ft. A chance of rain. .TUE NIGHT AND WED...S winds around 10 kt. Waves 1 foot or less, then around 2 ft. Rain likely. .WED NIGHT...W winds 10 to 15 kt. Waves around 2 ft. A chance of rain. 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. $$ ANZ236-221600- Narragansett Bay- 1004 PM EST Fri Nov 21 2025 .OVERNIGHT...W winds 5 to 10 kt. Waves around 2 ft. Showers. .SAT...N winds 5 to 10 kt. Waves around 2 ft. Showers in the morning with vsby 1 to 3 NM. .SAT NIGHT...NW winds 5 to 10 kt. Gusts up to 20 kt in the evening. Waves around 2 ft. .SUN...W winds 5 to 10 kt, becoming SW in the afternoon. Waves around 2 ft. .SUN NIGHT THROUGH MON NIGHT...W winds 5 to 10 kt. Waves around 2 ft. .TUE...SW winds 10 to 15 kt. Waves around 2 ft. A chance of rain. .TUE NIGHT AND WED...SW winds 10 to 15 kt with gusts up to 20 kt. Waves 2 to 3 ft. Rain likely. .WED NIGHT...W winds 10 to 15 kt with gusts up to 20 kt. Waves 2 to 4 ft. A chance of rain. Seas are reported as significant wave height, which is the average of the highest third of the waves. Individual wave heights may be more than twice the significant wave height. $$ For the latest updates...please visit our webpage at www.weather.gov/boston You can follow us on Facebook at www.facebook.com/NWSBoston You can follow us on Twitter at @NWSBoston