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:
The Knap surfForecast / Wales – South East / UK
48hr Weather and Surf, issued 5 pm Friday 12 Dec 2025 GMTForecast update in hr min s Forecast update imminent
Today's The Knap sea temperature is
9.7° C
(Which is 1.7°C colder than average for this time of year)How big are the waves at The Knap today?
The current surf forecast for The Knap at 11PM is: 0.6m 17s primary swell from a West direction (forecast issued at 05:00pm December 12). The wind direction is predicted to be cross-onshore.
| Time (GMT) & Date | Wave Height | Wave Period |
|---|---|---|
| Morning (12 Dec) | - | - |
| Afternoon (12 Dec) | 2.5ft (0.7m) | 18s |
| Evening (12 Dec) | 2ft (0.6m) | 17s |
Table - waves today at The Knap. (Swell directed towards the surf break)
Updates in hr min s Forecast update imminent
Friday 12 | Saturday 13 | Sunday 14 | Monday 15 | |||||||||||||||||||||
| 3 PM | 6 PM | 9 PM | 0 AM | 3 AM | 6 AM | 9 AM | 12 PM | 3 PM | 6 PM | 9 PM | 0 AM | 3 AM | 6 AM | 9 AM | 12 PM | 3 PM | 6 PM | 9 PM | 0 AM | 3 AM | 6 AM | 9 AM | 12 PM | |
Rating (10 max) | ||||||||||||||||||||||||
Swell Height Map |    |    |    |    | ||||||||||||||||||||
| Wave Height (m) & direction (?) | ||||||||||||||||||||||||
| Period(s) (?) | 18 | 18 | 17 | 17 | 17 | 16 | 16 | 15 | 15 | 14 | 14 | 8 | 9 | 9 | 12 | 10 | 12 | 12 | 12 | 12 | 12 | 12 | 12 | 12 |
Wave (?)Graph  | ||||||||||||||||||||||||
 kJ (?) | 311 | 225 | 220 | 215 | 202 | 131 | 126 | 119 | 109 | 67 | 96 | 37 | 40 | 42 | 46 | 47 | 137 | 134 | 132 | 132 | 132 | 101 | 101 | 96 |
Wind (km/h) | ||||||||||||||||||||||||
| Wind State (?) onshore cross-onshore cross-shore cross-offshore offshore glassy | cross | cross- on | cross- on | cross- on | cross- on | on | on | on | on | on | on | on | on | on | on | on | on | on | on | on | on | on | on | on |
High Tide / height (m) | 12:16PM 9.20 | 12:54AM 8.59 | 1:24PM 8.84 | 2:03AM 8.46 | 2:32PM 8.75 | 3:09AM 8.61 | ||||||||||||||||||
Low Tide / height (m) | 6:31PM 3.41 | 6:54AM 3.74 | 7:38PM 3.64 | 8:04AM 3.87 | 8:44PM 3.64 | 9:10AM 3.75 | ||||||||||||||||||
Friday 12 | Saturday 13 | Sunday 14 | Monday 15 | |||||||||||||||||||||
| Sunrise | - | - | - | - | - | - | 8:08 | - | - | - | - | - | - | - | 8:10 | - | - | - | - | - | - | - | 8:11 | - |
| Sunset | 4:04 | - | - | - | - | - | - | - | 4:04 | - | - | - | - | - | - | - | 4:04 | - | - | - | - | - | - | - |
 |  | |  | | |  | |  |  | | | | | | | | | | |  | |  | | |
Rain (mm) | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | 1 | 4 | 3 | 3 |
| Temp. °C | 10 | 10 | 9 | 9 | 9 | 9 | 9 | 9 | 10 | 9 | 8 | 8 | 9 | 9 | 10 | 10 | 11 | 10 | 11 | 12 | 12 | 11 | 11 | 11 |
| Feels °C (?) | 7 | 7 | 6 | 6 | 6 | 6 | 6 | 5 | 6 | 5 | 3 | 3 | 4 | 3 | 4 | 4 | 5 | 4 | 5 | 6 | 6 | 6 | 7 | 7 |
- 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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