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Surf Forecasts:
Green Harbor surfForecast / Massachusetts / USA
48hr Weather and Surf, issued 6 am Thursday 11 Dec 2025 ESTForecast update in hr min s Forecast update imminent
Green Harbor surf forecast is for near shore open water. Breaking waves will often be smaller at less exposed spots.
Today's Green Harbor sea temperature is
8.0° C
(Which is normal for this time of year)How big are the waves at Green Harbor today?
The current surf forecast for Green Harbor at 10AM is: 0.9m 4s primary swell from a West-northwest direction and 0.1m 7s secondary swell from a Southeast direction, 0.1m 10s secondary swell from a Southeast direction (forecast issued at 06:00am December 11). The wind direction is predicted to be cross-onshore.
| Time (EST) & Date | Wave Height | Wave Period |
|---|---|---|
| Morning (11 Dec) | 3ft (0.9m) | 4s |
| Afternoon (11 Dec) | 3.5ft (1.1m) | 4s |
| Evening (11 Dec) | 3.5ft (1.1m) | 4s |
Table - waves today at Green Harbor. (Swell directed towards the surf break)
Updates in hr min s Forecast update imminent
Thursday 11 | Friday 12 | Saturday 13 | Sun 14 | |||||||||||||||||||||
| 4 AM | 7 AM | 10 AM | 1 PM | 4 PM | 7 PM | 10 PM | 1 AM | 4 AM | 7 AM | 10 AM | 1 PM | 4 PM | 7 PM | 10 PM | 1 AM | 4 AM | 7 AM | 10 AM | 1 PM | 4 PM | 7 PM | 10 PM | 1 AM | |
Rating (10 max) | ||||||||||||||||||||||||
Swell Height Map |    |    |    |    | ||||||||||||||||||||
| Wave Height (m) & direction (?) | ||||||||||||||||||||||||
| Period(s) (?) | 3 | 3 | 4 | 4 | 4 | 4 | 4 | 5 | 5 | 5 | 5 | 4 | 4 | 4 | 4 | 4 | 4 | 10 | 11 | 3 | 3 | 3 | 3 | 16 |
Wave (?)Graph  | ||||||||||||||||||||||||
 kJ (?) | 10 | 11 | 22 | 42 | 46 | 52 | 50 | 63 | 57 | 57 | 48 | 29 | 28 | 20 | 19 | 15 | 7 | 2 | 2 | 3 | 6 | 5 | 5 | 5 |
Wind (km/h) | ||||||||||||||||||||||||
| Wind State (?) onshore cross-onshore cross-shore cross-offshore offshore glassy | on | cross- on | cross- on | cross- on | cross- on | cross- on | cross- on | cross- on | cross- on | cross- on | cross- on | cross- on | cross- on | cross- on | cross- on | cross- on | cross- on | on | on | on | on | on | cross- on | cross |
High Tide / height (m) | 4:08AM 2.76 | 4:27PM 2.86 | 5:07AM 2.74 | 5:28PM 2.69 | 6:04AM 2.74 | 6:30PM 2.57 | ||||||||||||||||||
Low Tide / height (m) | 10:10AM 0.26 | 10:44PM 0.09 | 11:12AM 0.31 | 11:39PM 0.22 | 12:14PM 0.33 | 12:34AM 0.32 | ||||||||||||||||||
Thursday 11 | Friday 12 | Saturday 13 | Sun 14 | |||||||||||||||||||||
| Sunrise | - | - | 7:00 | - | - | - | - | - | - | - | 7:01 | - | - | - | - | - | - | - | 7:01 | - | - | - | - | - |
| Sunset | - | - | - | - | 4:09 | - | - | - | - | - | - | - | 4:09 | - | - | - | - | - | - | - | 4:10 | - | - | - |
 | |  | | | | | | | | | | | | |  | | |  | | | | | | |
Rain (mm) | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - |
| Temp. °C | 5 | 2 | -1 | -1 | -2 | -3 | -3 | -4 | -5 | -5 | -3 | -1 | 0 | -1 | -2 | -2 | -2 | -2 | 0 | 3 | 3 | 2 | 2 | -1 |
| Feels °C (?) | -2 | -7 | -11 | -12 | -13 | -13 | -14 | -15 | -16 | -16 | -13 | -11 | -9 | -10 | -10 | -10 | -8 | -8 | -7 | -4 | -3 | -5 | -5 | -8 |
- Map Icons:
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Live Wave Height (m)
Live Wind Speed (km/h)
Surf Rating (10 Max)
Ocean Swells (m)- Wind Speed (km/h)
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