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:
Shida surfForecast / Chiba / Japan
48hr Weather and Surf, issued 2 am Saturday 13 Dec 2025 JSTForecast update in hr min s Forecast update imminent
Shida surf forecast is for near shore open water. Breaking waves will often be smaller at less exposed spots.
Today's Shida sea temperature is
18.8° C
(Which is slightly cooler than normal)How big are the waves at Shida today?
The current surf forecast for Shida at 5AM is: 0.9m 9s primary swell from a Northeast direction and 0.5m 11s secondary swell from a East-southeast direction (forecast issued at 02:00am December 13). An open ocean swell of 1.4m 9s is not directed at the surf break. The wind direction is predicted to be onshore.
| Time (JST) & Date | Wave Height | Wave Period |
|---|---|---|
| Morning (13 Dec) | 3.5ft (1.1m) | 9s |
| Afternoon (13 Dec) | 2ft (0.6m) | 12s |
| Evening (13 Dec) | 2ft (0.6m) | 11s |
Table - waves today at Shida. (Swell directed towards the surf break)
Updates in hr min s Forecast update imminent
Saturday 13 | Sunday 14 | Monday 15 | ||||||||||||||||||||||
| 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 | 3 PM | 6 PM | 9 PM | |
Rating (10 max) | ||||||||||||||||||||||||
Swell Height Map |    |    |    | |||||||||||||||||||||
| Wave Height (m) & direction (?) | ||||||||||||||||||||||||
| Period(s) (?) | 10 | 9 | 9 | 9 | 8 | 12 | 12 | 11 | 11 | 7 | 7 | 8 | 8 | 9 | 11 | 11 | 11 | 10 | 10 | 10 | 10 | 10 | 10 | 9 |
Wave (?)Graph  | ||||||||||||||||||||||||
 kJ (?) | 535 | 415 | 135 | 197 | 169 | 109 | 109 | 102 | 18 | 392 | 435 | 402 | 522 | 840 | 1862 | 2540 | 3071 | 918 | 590 | 320 | 178 | 125 | 68 | 84 |
Wind (km/h) | ||||||||||||||||||||||||
| Wind State (?) onshore cross-onshore cross-shore cross-offshore offshore glassy | on | on | on | on | cross- on | cross | cross | cross- off | cross- off | cross- on | cross- on | cross- on | cross- on | cross- off | cross- off | cross | cross | cross- on | cross- on | cross- on | cross- on | cross- on | on | on |
High Tide / height (m) | 9:42PM 1.03 | 10:52AM 1.30 | 11:49PM 1.00 | 11:30AM 1.31 | 1:34AM 1.06 | 12:07PM 1.33 | ||||||||||||||||||
Low Tide / height (m) | 3:48AM 0.67 | 5:55PM 0.68 | 4:48AM 0.80 | 6:51PM 0.54 | 5:59AM 0.90 | 7:35PM 0.42 | ||||||||||||||||||
Saturday 13 | Sunday 14 | Monday 15 | ||||||||||||||||||||||
| Sunrise | - | - | - | 6:37 | - | - | - | - | - | - | - | 6:37 | - | - | - | - | - | - | - | 6:39 | - | - | - | - |
| Sunset | - | - | - | - | - | 4:25 | - | - | - | - | - | - | - | 4:25 | - | - | - | - | - | - | - | 4:25 | - | - |
 | | |  | | | |  | | | |  | |  |  | | | | |  | | | | | |
Rain (mm) | - | - | - | - | - | - | - | 3 | 3 | 3 | 2 | 3 | 1 | - | - | - | - | - | - | - | - | - | - | - |
| Temp. °C | 4 | 5 | 5 | 6 | 7 | 8 | 10 | 11 | 13 | 7 | 7 | 8 | 9 | 10 | 11 | 10 | 10 | 10 | 9 | 9 | 11 | 12 | 10 | 9 |
| Feels °C (?) | -3 | -1 | -1 | 1 | 3 | 4 | 6 | 6 | 7 | 2 | 4 | 5 | 5 | 6 | 5 | 5 | 5 | 4 | 3 | 2 | 4 | 6 | 4 | 4 |
- 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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