FZUS51 KBOX 162016 CWFBOX Coastal Waters Forecast for Massachusetts and Rhode Island National Weather Service Boston/Norton MA 416 PM EDT Thu Apr 16 2026 Coastal waters from the Merrimack River MA to Watch Hill RI out to 25 NM ANZ200-170900- 416 PM EDT Thu Apr 16 2026 .Synopsis for Massachusetts and Rhode Island coastal waters... A backdoor cold front remains over northern New England that may cross through the northern MA waters again today. A cold front likely crosses waters sometime Fri/Fri night followed by a stronger cold front sometime Sun/Sun night. Early next week, high pres builds from the Great Lakes to the Mid Atlantic. $$ ANZ250-170900- Coastal waters east of Ipswich Bay and the Stellwagen Bank National Marine Sanctuary- 416 PM EDT Thu Apr 16 2026 .TONIGHT...S winds 5 to 10 kt, becoming SW after midnight. Seas around 2 ft. Patchy fog. A slight chance of tstms. A slight chance of showers this evening, then a chance of showers after midnight. Vsby 1 NM or less. .FRI...W winds 5 to 10 kt, becoming NE in the afternoon. Seas around 2 ft. Patchy fog in the morning. A chance of showers in the morning with vsby 1 NM or less. .FRI NIGHT...NE winds 5 to 10 kt. Seas around 2 ft. .SAT...NE winds 5 to 10 kt. Seas around 2 ft. .SAT NIGHT...E winds 5 to 10 kt, becoming S after midnight. Seas around 2 ft. .SUN AND SUN NIGHT...W winds 15 to 20 kt with gusts up to 25 kt. Seas 2 to 4 ft. A chance of showers in the morning, then showers likely through the night. A chance of showers after midnight. .MON THROUGH TUE...W winds 15 to 20 kt with gusts up to 25 kt. Seas 2 to 4 ft. .TUE NIGHT...SW winds 15 to 20 kt with gusts up to 25 kt. Seas 3 to 5 ft. Winds and seas higher in and near tstms. Seas are reported as significant wave height, which is the average of the highest third of the waves. Individual wave heights may be more than twice the significant wave height. $$ ANZ251-170900- Massachusetts Bay and Ipswich Bay- 416 PM EDT Thu Apr 16 2026 .TONIGHT...SE winds 5 to 10 kt, becoming SW after midnight. Seas around 2 ft. Patchy fog. A slight chance of showers. A slight chance of tstms this evening. Vsby 1 NM or less. .FRI...W winds 5 to 10 kt, becoming NE in the afternoon. Seas 1 foot or less, then around 2 ft in the afternoon. A chance of showers. Patchy fog in the morning with vsby 1 NM or less. .FRI NIGHT...NE winds 5 to 10 kt. Seas around 2 ft. .SAT...NE winds 5 to 10 kt. Seas around 2 ft. .SAT NIGHT...E winds 5 to 10 kt, becoming S after midnight. Seas around 2 ft. .SUN AND SUN NIGHT...W winds 15 to 20 kt. Seas 2 to 3 ft. Showers likely . .MON THROUGH TUE NIGHT...SW winds 15 to 20 kt. Seas 2 to 4 ft. Winds and seas higher in and near tstms. Seas are reported as significant wave height, which is the average of the highest third of the waves. Individual wave heights may be more than twice the significant wave height. $$ ANZ231-170900- Cape Cod Bay- 416 PM EDT Thu Apr 16 2026 .TONIGHT...SW winds 5 to 10 kt. Seas around 2 ft. Patchy fog. A slight chance of showers and tstms. Vsby 1 NM or less, increasing to 1 to 3 NM after midnight. .FRI...W winds 5 to 10 kt, becoming N in the afternoon. Seas 1 foot or less. Patchy fog in the morning. A chance of showers in the morning with vsby 1 NM or less. .FRI NIGHT...NE winds 5 to 10 kt. Seas 1 foot or less. .SAT...NE winds 5 to 10 kt. Seas 1 foot or less. Patchy fog in the morning. .SAT NIGHT...SE winds 5 to 10 kt. Seas 1 foot or less. .SUN AND SUN NIGHT...W winds 15 to 20 kt. Seas 2 to 3 ft. A chance of showers in the morning, then showers likely through the night. A chance of showers after midnight. .MON THROUGH TUE NIGHT...SW winds 15 to 20 kt. Seas 2 to 3 ft. Winds and seas higher in and near tstms. Seas are reported as significant wave height, which is the average of the highest third of the waves. Individual wave heights may be more than twice the significant wave height. $$ ANZ254-170900- Coastal waters from Provincetown MA to Chatham MA to Nantucket MA out 20 NM- 416 PM EDT Thu Apr 16 2026 .TONIGHT...SW winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to 4 ft. Patchy fog. A slight chance of showers and tstms after midnight. Vsby 1 NM or less. .FRI...W winds 5 to 10 kt, becoming N in the afternoon. Seas 2 to 4 ft. Patchy fog. A chance of showers in the morning. Vsby 1 NM or less, increasing to 1 to 3 NM in the afternoon. .FRI NIGHT...NE winds 5 to 10 kt. Seas 2 to 3 ft. Patchy fog after midnight. .SAT...NE winds 5 to 10 kt. Seas 2 to 3 ft. Patchy fog in the morning. .SAT NIGHT...E winds 5 to 10 kt, becoming S after midnight. Seas 2 to 3 ft. .SUN...S winds 10 to 15 kt with gusts up to 20 kt. Seas 2 to 4 ft. A chance of showers in the morning, then showers likely in the afternoon. .SUN NIGHT...W winds 15 to 20 kt with gusts up to 25 kt. Seas 3 to 5 ft. Showers likely, mainly in the evening. .MON...NW winds 15 to 20 kt with gusts up to 25 kt. Seas 3 to 5 ft. .MON NIGHT AND TUE...NW winds 15 to 20 kt. Seas 2 to 4 ft. .TUE NIGHT...SW winds 15 to 20 kt with gusts up to 25 kt. Seas 3 to 5 ft. Winds and seas higher in and near tstms. Seas are reported as significant wave height, which is the average of the highest third of the waves. Individual wave heights may be more than twice the significant wave height. $$ ANZ255-170900- Coastal Waters extending out to 25 NM South of Marthas Vineyard and Nantucket- 416 PM EDT Thu Apr 16 2026 .TONIGHT...SW winds 10 to 15 kt with gusts up to 20 kt. Seas 3 to 5 ft. Patchy fog. Vsby 1 NM or less. .FRI...W winds 10 to 15 kt, diminishing to 5 to 10 kt in the afternoon. Seas 3 to 5 ft. Patchy fog. A chance of showers in the morning. Vsby 1 NM or less, increasing to 1 to 3 NM in the afternoon. .FRI NIGHT...NE winds 5 to 10 kt. Seas 3 to 4 ft. Patchy fog. .SAT...NE winds 5 to 10 kt. Seas 2 to 3 ft. Patchy fog in the morning. .SAT NIGHT...E winds 5 to 10 kt, becoming S after midnight. Seas 2 to 3 ft. .SUN...S winds 10 to 15 kt, becoming SW 15 to 20 kt in the afternoon. Seas 2 to 3 ft, building to 3 to 5 ft in the afternoon. A chance of showers in the morning, then showers likely in the afternoon. .SUN NIGHT...W winds 20 to 25 kt. Seas 4 to 6 ft. Showers likely, mainly in the evening. .MON...W winds 20 to 25 kt. Seas 4 to 6 ft. .MON NIGHT...NW winds 15 to 20 kt with gusts up to 25 kt. Seas 3 to 5 ft. .TUE...W winds 15 to 20 kt with gusts up to 25 kt. Seas 2 to 4 ft. .TUE NIGHT...SW winds 20 to 25 kt. Seas 4 to 6 ft. Seas are reported as significant wave height, which is the average of the highest third of the waves. Individual wave heights may be more than twice the significant wave height. $$ ANZ256-170900- Coastal Waters from Montauk NY to Marthas Vineyard extending out to 20 NM South of Block Island- 416 PM EDT Thu Apr 16 2026 .TONIGHT...SW winds 10 to 15 kt with gusts up to 20 kt. Seas 3 to 5 ft. Patchy fog. Vsby 1 NM or less. .FRI...W winds 5 to 10 kt. Seas 4 to 5 ft. A chance of showers. Patchy fog in the morning with vsby 1 NM or less. .FRI NIGHT...NE winds 5 to 10 kt. Seas 3 to 4 ft. .SAT...NE winds 10 to 15 kt. Seas 2 to 3 ft. Patchy fog in the morning. .SAT NIGHT...E winds 5 to 10 kt, becoming SE after midnight. Seas 2 to 3 ft. .SUN...S winds 10 to 15 kt, becoming W 15 to 20 kt in the afternoon. Seas 2 to 4 ft. A chance of showers in the morning, then showers likely in the afternoon. .SUN NIGHT...W winds 20 to 25 kt. Seas 4 to 5 ft. Showers likely, mainly in the evening. .MON AND MON NIGHT...NW winds 20 to 25 kt. Seas 3 to 5 ft. .TUE...W winds 15 to 20 kt with gusts up to 25 kt. Seas 2 to 4 ft. .TUE NIGHT...SW 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. $$ ANZ232-170900- Nantucket Sound- 416 PM EDT Thu Apr 16 2026 .TONIGHT...SW winds 10 to 15 kt. Gusts up to 20 kt after midnight. Seas 2 to 3 ft. Patchy fog. Vsby 1 NM or less. .FRI...W winds 5 to 10 kt, becoming NW in the afternoon. Seas 2 to 3 ft. Patchy fog in the morning. A chance of showers in the morning with vsby 1 NM or less. .FRI NIGHT...NE winds 5 to 10 kt. Seas around 2 ft. Patchy fog after midnight. .SAT...NE winds 5 to 10 kt. Seas around 2 ft. Patchy fog in the morning. .SAT NIGHT...E winds 5 to 10 kt, becoming S after midnight. Seas around 2 ft. .SUN...S winds 10 to 15 kt, becoming SW in the afternoon. Gusts up to 20 kt. Seas 2 to 3 ft. A chance of showers in the morning, then showers likely in the afternoon. .SUN NIGHT...W winds 15 to 20 kt with gusts up to 25 kt. Seas 2 to 3 ft. Showers likely, mainly in the evening. .MON THROUGH TUE NIGHT...SW winds 15 to 20 kt with gusts up to 25 kt. Seas 2 to 4 ft. Seas are reported as significant wave height, which is the average of the highest third of the waves. Individual wave heights may be more than twice the significant wave height. $$ ANZ233-170900- Vineyard Sound- 416 PM EDT Thu Apr 16 2026 .TONIGHT...SW winds 10 to 15 kt. Seas 2 to 3 ft. Patchy fog. Vsby 1 NM or less. .FRI...SW winds 5 to 10 kt, becoming NW in the afternoon. Seas 2 to 3 ft. A chance of showers. Patchy fog in the morning with vsby 1 to 3 NM. .FRI NIGHT...NE winds 5 to 10 kt. Seas 2 to 3 ft. Patchy fog after midnight. .SAT...NE winds around 10 kt. Seas around 2 ft. Patchy fog in the morning. .SAT NIGHT...E winds 5 to 10 kt, becoming SE after midnight. Seas around 2 ft. .SUN...S winds 10 to 15 kt, becoming W in the afternoon. Gusts up to 20 kt. Seas 2 to 3 ft. A chance of showers in the morning, then showers likely in the afternoon. .SUN NIGHT...W winds 15 to 20 kt with gusts up to 25 kt. Seas 2 to 3 ft. Showers likely, mainly in the evening. .MON THROUGH TUE NIGHT...SW winds 20 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. $$ ANZ234-170900- Buzzards Bay- 416 PM EDT Thu Apr 16 2026 .TONIGHT...SW winds 10 to 15 kt. Seas around 2 ft. Patchy fog. A slight chance of showers after midnight. Vsby 1 NM or less. .FRI...SW winds 5 to 10 kt, becoming NW in the afternoon. Seas around 2 ft. A chance of showers. Patchy fog in the morning with vsby 1 NM or less. .FRI NIGHT...NE winds 5 to 10 kt. Seas around 2 ft. A chance of showers in the evening. .SAT...NE winds around 10 kt. Seas around 2 ft. Patchy fog in the morning. .SAT NIGHT...E winds 5 to 10 kt, becoming S after midnight. Seas around 2 ft in the evening, then 1 foot or less. .SUN...S winds 10 to 15 kt, becoming W in the afternoon. Gusts up to 20 kt. Seas 2 to 3 ft. A chance of showers in the morning, then showers likely in the afternoon. .SUN NIGHT...W winds 15 to 20 kt. Seas 2 to 3 ft. Showers likely, mainly in the evening. .MON THROUGH TUE NIGHT...SW winds 20 to 25 kt. Seas 2 to 4 ft. Seas are reported as significant wave height, which is the average of the highest third of the waves. Individual wave heights may be more than twice the significant wave height. $$ ANZ235-170900- Rhode Island Sound- 416 PM EDT Thu Apr 16 2026 .TONIGHT...SW winds 10 to 15 kt with gusts up to 20 kt. Seas 3 to 4 ft. Patchy fog. Vsby 1 NM or less. .FRI...W winds 5 to 10 kt. Seas 3 to 4 ft. A chance of showers. Patchy fog in the morning with vsby 1 to 3 NM. .FRI NIGHT...NE winds around 10 kt. Seas 2 to 3 ft. A chance of showers in the evening. .SAT...NE winds around 10 kt. Seas 2 to 3 ft. Patchy fog in the morning. .SAT NIGHT...E winds 5 to 10 kt, becoming SE after midnight. Seas around 2 ft. .SUN...S winds 10 to 15 kt, becoming W 15 to 20 kt in the afternoon. Seas 2 to 4 ft. A chance of showers in the morning, then showers likely in the afternoon. .SUN NIGHT...W winds 15 to 20 kt with gusts up to 25 kt. Seas 3 to 4 ft. Showers likely, mainly in the evening. .MON THROUGH TUE...W winds 15 to 20 kt with gusts up to 25 kt. Seas 2 to 4 ft. .TUE NIGHT...SW winds 20 to 25 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. $$ ANZ237-170900- Block Island Sound- 416 PM EDT Thu Apr 16 2026 .TONIGHT...SW winds 10 to 15 kt, diminishing to 5 to 10 kt after midnight. Gusts up to 20 kt. Seas 2 to 4 ft. Patchy fog this evening with vsby 1 NM or less. .FRI...W winds 5 to 10 kt. Seas 2 to 4 ft. A chance of showers. Patchy fog in the morning with vsby 1 to 3 NM. .FRI NIGHT...NE winds 5 to 10 kt. Seas 2 to 3 ft. A chance of showers in the evening. .SAT...E winds 5 to 10 kt. Seas 2 to 3 ft. .SAT NIGHT...SE winds 5 to 10 kt. Seas around 2 ft. .SUN...S winds 10 to 15 kt, becoming W in the afternoon. Gusts up to 20 kt. Seas 2 to 3 ft. Showers likely. .SUN NIGHT...NW winds 15 to 20 kt. Seas 2 to 3 ft. Showers likely, mainly in the evening. .MON THROUGH TUE...W winds 15 to 20 kt. Seas 2 to 3 ft. .TUE NIGHT...SW winds 15 to 20 kt with gusts up to 25 kt. Seas 3 to 5 ft. Seas are reported as significant wave height, which is the average of the highest third of the waves. Individual wave heights may be more than twice the significant wave height. $$ ANZ230-170900- Boston Harbor- 416 PM EDT Thu Apr 16 2026 .TONIGHT...SE winds 5 to 10 kt, becoming SW after midnight. Waves 1 foot or less. Patchy fog. A slight chance of showers. A slight chance of tstms this evening. Vsby 1 NM or less. .FRI...W winds around 5 kt, becoming NE in the afternoon. Waves 1 foot or less. A chance of showers. Patchy fog in the morning with vsby 1 NM or less. .FRI NIGHT...NE winds 5 to 10 kt. Waves 1 foot or less. .SAT...NE winds 5 to 10 kt. Waves 1 foot or less. .SAT NIGHT...E winds 5 to 10 kt, becoming S after midnight. Waves 1 foot or less. .SUN...S winds 10 to 15 kt, becoming W with gusts up to 20 kt in the afternoon. Waves around 2 ft. Showers likely. .SUN NIGHT...W winds 15 to 20 kt. Waves around 2 ft. Showers likely, mainly in the evening. .MON THROUGH TUE NIGHT...SW winds 15 to 20 kt. Waves around 2 ft. Winds and waves higher in and near tstms. Seas are reported as significant wave height, which is the average of the highest third of the waves. Individual wave heights may be more than twice the significant wave height. $$ ANZ236-170900- Narragansett Bay- 416 PM EDT Thu Apr 16 2026 .TONIGHT...S winds 10 to 15 kt, becoming SW 5 to 10 kt after midnight. Waves around 2 ft. A slight chance of with patchy fog. Vsby 1 to 3 NM. .FRI...SW winds around 5 kt, becoming NW in the afternoon. Waves around 2 ft. A chance of showers. Patchy fog in the morning with vsby 1 to 3 NM. .FRI NIGHT...NE winds 5 to 10 kt. Waves around 2 ft. A chance of showers in the evening. .SAT...NE winds 5 to 10 kt. Waves around 2 ft. .SAT NIGHT...SE winds 5 to 10 kt. Waves around 2 ft. .SUN...S winds 10 to 15 kt, becoming W with gusts up to 20 kt in the afternoon. Waves around 2 ft. Showers likely. .SUN NIGHT...W winds 10 to 15 kt with gusts up to 20 kt. Waves around 2 ft. Showers likely, mainly in the evening. .MON THROUGH TUE NIGHT...SW winds 10 to 15 kt with gusts up to 20 kt. Waves 2 to 4 ft. Seas are reported as significant wave height, which is the average of the highest third of the waves. Individual wave heights may be more than twice the significant wave height. $$ ANZ280-170900- Ocean Waters from the Merrimack River to Plymouth from 40 to 60 NM- 416 PM EDT Thu Apr 16 2026 .TONIGHT...S winds 10 to 15 kt, becoming SW with gusts up to 20 kt after midnight. Seas 2 to 3 ft. Patchy fog. A chance of showers with a slight chance of tstms. Vsby 1 NM or less. .FRI...W winds 5 to 10 kt, becoming NE in the afternoon. Seas 2 to 3 ft. Patchy fog. A chance of showers in the morning with vsby 1 NM or less. .FRI NIGHT...NE winds 5 to 10 kt. Seas around 3 ft. .SAT...E winds around 10 kt. Seas 2 to 3 ft. .SAT NIGHT...SE winds around 10 kt, becoming S after midnight. Seas 2 to 3 ft. .SUN...S winds 10 to 15 kt, becoming SW 15 to 20 kt in the afternoon. Gusts up to 25 kt. Seas 2 to 4 ft. A chance of showers in the morning, then showers likely in the afternoon. .SUN NIGHT...W winds 15 to 20 kt, increasing to 20 to 25 kt after midnight. Seas 4 to 5 ft. Showers likely, mainly in the evening. .MON AND MON NIGHT...NW winds 20 to 25 kt, diminishing to 15 to 20 kt. Seas 3 to 5 ft. .TUE...W winds 15 to 20 kt with gusts up to 25 kt. Seas 2 to 4 ft. .TUE NIGHT...SW winds 20 to 25 kt with gusts up to 30 kt. Seas 4 to 6 ft. Winds and seas higher in and near tstms. Seas are reported as significant wave height, which is the average of the highest third of the waves. Individual wave heights may be more than twice the significant wave height. $$ ANZ281-170900- Ocean Waters from Provincetown to Nantucket from 20 to 60 NM- 416 PM EDT Thu Apr 16 2026 .TONIGHT...SW winds 10 to 15 kt with gusts up to 20 kt. Seas 3 to 5 ft. Patchy fog. A slight chance of showers after midnight. Vsby 1 NM or less. .FRI...SW winds 10 to 15 kt with gusts up to 20 kt, becoming NW 5 to 10 kt in the afternoon. Seas 3 to 5 ft. Patchy fog. A chance of showers in the morning. Vsby 1 NM or less. .FRI NIGHT...NE winds 5 to 10 kt. Seas 3 to 4 ft. .SAT...NE winds 5 to 10 kt. Seas 3 to 4 ft. Patchy fog in the morning. .SAT NIGHT...E winds 5 to 10 kt, becoming S after midnight. Seas around 3 ft. .SUN...S winds 10 to 15 kt, becoming SW 15 to 20 kt in the afternoon. Gusts up to 25 kt. Seas 3 to 5 ft. A chance of showers in the afternoon. .SUN NIGHT...W winds 15 to 20 kt, increasing to 20 to 25 kt after midnight. Seas 4 to 6 ft. Showers likely, mainly in the evening. .MON...W winds 20 to 25 kt. Seas 4 to 6 ft. .MON NIGHT AND TUE...NW winds 15 to 20 kt with gusts up to 25 kt. Seas 3 to 5 ft. .TUE NIGHT...SW winds 20 to 25 kt. Seas 4 to 6 ft. Seas are reported as significant wave height, which is the average of the highest third of the waves. Individual wave heights may be more than twice the significant wave height. $$ ANZ282-170900- Ocean Waters from Marthas Vineyard to Nantucket from 25 to 60 NM- 416 PM EDT Thu Apr 16 2026 .TONIGHT...SW winds 15 to 20 kt with gusts up to 25 kt. Seas 4 to 6 ft. Patchy fog. Vsby 1 NM or less. .FRI...SW winds 10 to 15 kt with gusts up to 20 kt, becoming W 5 to 10 kt in the afternoon. Seas 4 to 6 ft. Patchy fog. Vsby 1 NM or less. .FRI NIGHT...NE winds 5 to 10 kt. Seas 3 to 5 ft. Patchy fog. Vsby 1 NM or less in the evening. .SAT...NE winds 5 to 10 kt. Seas 3 to 4 ft. Patchy fog in the morning. .SAT NIGHT...E winds 5 to 10 kt, becoming S after midnight. Seas 2 to 3 ft. .SUN...S winds 10 to 15 kt, becoming SW 15 to 20 kt in the afternoon. Gusts up to 25 kt. Seas 3 to 5 ft. Showers likely in the afternoon. .SUN NIGHT...W winds 20 to 25 kt. Seas 5 to 6 ft. Showers likely, mainly in the evening. .MON AND MON NIGHT...W winds 20 to 25 kt, becoming NW 15 to 20 kt. Seas 4 to 6 ft. .TUE...NW winds 15 to 20 kt with gusts up to 25 kt. Seas 3 to 5 ft. .TUE NIGHT...SW 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. $$ ANZ283-170900- Ocean Waters from Montauk NY to Marthas Vineyard from 25 to 60 NM- 416 PM EDT Thu Apr 16 2026 .TONIGHT...SW winds 15 to 20 kt with gusts up to 25 kt. Seas 4 to 6 ft. Patchy fog. Vsby 1 NM or less. .FRI...W winds 10 to 15 kt with gusts up to 20 kt, diminishing to 5 to 10 kt in the afternoon. Seas 4 to 5 ft. Patchy fog in the morning with vsby 1 NM or less. .FRI NIGHT...NE winds 5 to 10 kt. Seas 3 to 4 ft. .SAT...NE winds 10 to 15 kt, diminishing to 5 to 10 kt in the afternoon. Seas around 3 ft. .SAT NIGHT...E winds 5 to 10 kt, becoming S 10 to 15 kt after midnight. Seas 2 to 3 ft. .SUN...S winds 15 to 20 kt, becoming W in the afternoon. Gusts up to 25 kt. Seas 3 to 5 ft. A chance of showers in the morning, then showers likely in the afternoon. .SUN NIGHT...W winds 20 to 25 kt. Seas 5 to 6 ft. Showers likely, mainly in the evening. .MON AND MON NIGHT...NW winds 20 to 25 kt. Seas 4 to 6 ft. .TUE...W winds 15 to 20 kt with gusts up to 25 kt. Seas 3 to 4 ft. .TUE NIGHT...SW winds 20 to 25 kt. Seas 4 to 6 ft. Seas are reported as significant wave height, which is the average of the highest third of the waves. Individual wave heights may be more than twice the significant wave height. $$