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:
Arniston surfForecast / Overberg / South Africa
48hr Weather and Surf, issued 7 am Saturday 13 Dec 2025 SASTForecast update in hr min s Forecast update imminent
Arniston surf forecast is for near shore open water. Breaking waves will often be smaller at less exposed spots.
Today's Arniston sea temperature is
20.5° C
(Which is 1.0°C warmer than normal for this time of year)How big are the waves at Arniston today?
The current surf forecast for Arniston at 9AM is: 3.5m 14s primary swell from a Southwest direction and 2.4m 14s secondary swell from a South-southwest direction, 0.4m 10s secondary swell from a East direction (forecast issued at 07:00am December 13). The wind direction is predicted to be cross-offshore and the swell rating is 11.
| Time (SAST) & Date | Wave Height | Wave Period |
|---|---|---|
| Morning (13 Dec) | 11ft (3.5m) | 14s |
| Afternoon (13 Dec) | 7ft (2.1m) | 13s |
| Evening (13 Dec) | 5ft (1.6m) | 13s |
Table - waves today at Arniston. (Swell directed towards the surf break)
Updates in hr min s Forecast update imminent
Saturday 13 | Sunday 14 | Monday 15 | Tue 16 | |||||||||||||||||||||
| 5 AM | 8 AM | 11 AM | 2 PM | 5 PM | 8 PM | 11 PM | 2 AM | 5 AM | 8 AM | 11 AM | 2 PM | 5 PM | 8 PM | 11 PM | 2 AM | 5 AM | 8 AM | 11 AM | 2 PM | 5 PM | 8 PM | 11 PM | 2 AM | |
Rating (10 max) | ||||||||||||||||||||||||
Swell Height Map |    |    |    |    | ||||||||||||||||||||
| Wave Height (m) & direction (?) | ||||||||||||||||||||||||
| Period(s) (?) | 12 | 14 | 13 | 13 | 13 | 14 | 13 | 13 | 12 | 12 | 12 | 12 | 12 | 12 | 12 | 12 | 12 | 12 | 12 | 12 | 12 | 12 | 13 | 13 |
Wave (?)Graph  | ||||||||||||||||||||||||
 kJ (?) | 2987 | 4435 | 3567 | 1597 | 1086 | 1004 | 799 | 838 | 787 | 787 | 692 | 605 | 569 | 787 | 890 | 890 | 965 | 949 | 934 | 949 | 857 | 849 | 809 | 725 |
Wind (km/h) | ||||||||||||||||||||||||
| Wind State (?) onshore cross-onshore cross-shore cross-offshore offshore glassy | cross- off | cross- off | cross- off | cross- off | cross- off | cross- off | cross- off | cross- off | cross- off | off | cross | cross | cross | cross | glass | glass | cross- off | glass | on | cross- on | cross | cross- on | cross- on | cross- on |
High Tide / height (m) | 10:31AM 1.42 | 11:21PM 1.23 | 11:32AM 1.44 | 12:20AM 1.30 | 12:23PM 1.49 | 1:04AM 1.39 | ||||||||||||||||||
Low Tide / height (m) | 5:20PM 0.63 | 5:13AM 0.71 | 6:16PM 0.56 | 6:14AM 0.67 | 6:59PM 0.48 | |||||||||||||||||||
Saturday 13 | Sunday 14 | Monday 15 | Tue 16 | |||||||||||||||||||||
| Sunrise | - | 5:18 | - | - | - | - | - | - | - | 5:18 | - | - | - | - | - | - | - | 5:18 | - | - | - | - | - | - |
| Sunset | - | - | - | - | 7:45 | - | - | - | - | - | - | - | 7:46 | - | - | - | - | - | - | - | 7:46 | - | - | - |
 |  |  |  | |  |  | | | | | | | | | | | | | | | | | | |
Rain (mm) | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - |
| Temp. °C | 18 | 17 | 17 | 18 | 18 | 17 | 17 | 16 | 15 | 15 | 17 | 18 | 18 | 18 | 18 | 17 | 17 | 17 | 19 | 20 | 20 | 20 | 19 | 19 |
| Feels °C (?) | 10 | 10 | 10 | 11 | 11 | 12 | 14 | 13 | 13 | 13 | 14 | 14 | 15 | 17 | 18 | 17 | 17 | 17 | 18 | 17 | 18 | 20 | 19 | 19 |
- 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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