Nazare Big Wave Challenge Gets Yellow Alert, Could Run Saturday in Giant Waves
70-foot plus waves predicted for Portuguese big wave tow surfing competition.
Surf Forecasts:
Green Harbor surfForecast / Massachusetts / USA
48hr Weather and Surf, issued 12 pm Friday 12 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
7.8° 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 6PM is: 0.9m 4s primary swell from a West-northwest direction and 0.1m 10s secondary swell from a East direction (forecast issued at 12:00pm December 12). The wind direction is predicted to be cross-onshore.
| Time (EST) & Date | Wave Height | Wave Period |
|---|---|---|
| Morning (12 Dec) | 3.5ft (1.1m) | 4s |
| Afternoon (12 Dec) | 3.5ft (1.0m) | 4s |
| Evening (12 Dec) | 3ft (0.9m) | 4s |
Table - waves today at Green Harbor. (Swell directed towards the surf break)
Updates in hr min s Forecast update imminent
Friday 12 | Saturday 13 | Sunday 14 | Monday 15 | |||||||||||||||||||||
| 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 | 4 AM | 7 AM | |
Rating (10 max) | ||||||||||||||||||||||||
Swell Height Map |    |    |    |    | ||||||||||||||||||||
| Wave Height (m) & direction (?) | ||||||||||||||||||||||||
| Period(s) (?) | 4 | 5 | 4 | 4 | 4 | 4 | 4 | 3 | 3 | 3 | 3 | 17 | 3 | 10 | 10 | 10 | 3 | 9 | 15 | 15 | 15 | 6 | 10 | 6 |
Wave (?)Graph  | ||||||||||||||||||||||||
 kJ (?) | 52 | 45 | 43 | 33 | 31 | 17 | 7 | 2 | 2 | 3 | 6 | 6 | 3 | 2 | 2 | 2 | 4 | 2 | 4 | 4 | 5 | 73 | 10 | 55 |
Wind (km/h) | ||||||||||||||||||||||||
| Wind State (?) onshore cross-onshore cross-shore cross-offshore offshore glassy | cross- on | cross- on | cross- on | cross- on | cross- on | cross- on | cross- on | on | on | on | on | on | on | cross- on | cross- on | cross | cross | cross | cross | cross- off | cross | cross | cross | cross |
High Tide / height (m) | 5:28PM 2.69 | 6:04AM 2.74 | 6:30PM 2.57 | 7:00AM 2.75 | 7:30PM 2.49 | |||||||||||||||||||
Low Tide / height (m) | 11:12AM 0.31 | 11:39PM 0.22 | 12:14PM 0.33 | 12:34AM 0.32 | 1:14PM 0.32 | 1:26AM 0.41 | ||||||||||||||||||
Friday 12 | Saturday 13 | Sunday 14 | Monday 15 | |||||||||||||||||||||
| Sunrise | - | - | - | - | - | - | - | - | 7:01 | - | - | - | - | - | - | - | 7:01 | - | - | - | - | - | - | - |
| Sunset | - | - | 4:09 | - | - | - | - | - | - | - | 4:10 | - | - | - | - | - | - | - | 4:10 | - | - | - | - | - |
 | | |  | | |  | |  | | | | | | |  | | |  | | | | | | |
Rain (mm) | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - |
| Temp. °C | -3 | 0 | 1 | 0 | -1 | -2 | -2 | -1 | 1 | 4 | 3 | 3 | 2 | 1 | 0 | -3 | -2 | -1 | -1 | -3 | -4 | -6 | -7 | -7 |
| Feels °C (?) | -14 | -11 | -9 | -9 | -10 | -9 | -9 | -7 | -6 | -4 | -4 | -4 | -4 | -4 | -5 | -9 | -9 | -9 | -9 | -13 | -14 | -16 | -17 | -17 |
- Map Icons:
Break
Live Wave Height (m)
Live Wind Speed (km/h)
Surf Rating (10 Max)
Ocean Swells (m)- Wind Speed (km/h)
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