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:
Kugenuma Rivermouth surfForecast / Kanagawa / Japan
48hr Weather and Surf, issued 2 am Friday 12 Dec 2025 JSTForecast update in hr min s Forecast update imminent
Kugenuma Rivermouth surf forecast is for near shore open water. Breaking waves will often be smaller at less exposed spots.
Today's Kugenuma Rivermouth sea temperature is
18.4° C
(Which is 1.1°C colder than average for this time of year)How big are the waves at Kugenuma Rivermouth today?
The current surf forecast for Kugenuma Rivermouth at 5AM is: 0.7m 6s primary swell from a Southwest direction and 0.1m 11s secondary swell from a Southeast direction (forecast issued at 02:00am December 12). An open ocean swell of 0.7m 3s is not directed at the surf break. The wind direction is predicted to be offshore.
| Time (JST) & Date | Wave Height | Wave Period |
|---|---|---|
| Morning (12 Dec) | 1ft (0.3m) | 7s |
| Afternoon (12 Dec) | 0.5ft (0.1m) | 11s |
| Evening (12 Dec) | 0.5ft (0.1m) | 10s |
Table - waves today at Kugenuma Rivermouth. (Swell directed towards the surf break)
Updates in hr min s Forecast update imminent
Friday 12 | Saturday 13 | Sunday 14 | ||||||||||||||||||||||
| 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) (?) | 6 | 7 | 6 | 7 | 11 | 11 | 11 | 10 | 12 | 15 | 15 | 14 | 14 | 11 | 11 | 11 | 6 | 6 | 6 | 7 | 9 | 10 | 10 | 10 |
Wave (?)Graph  | ||||||||||||||||||||||||
 kJ (?) | 273 | 114 | 27 | 10 | 4 | 4 | 2 | 2 | 3 | 4 | 4 | 4 | 4 | 2 | 2 | 23 | 11 | 14 | 14 | 23 | 138 | 284 | 455 | 460 |
Wind (km/h) | ||||||||||||||||||||||||
| Wind State (?) onshore cross-onshore cross-shore cross-offshore offshore glassy | cross- on | off | off | off | off | off | off | off | off | off | off | off | cross- off | off | off | off | off | off | off | off | off | on | cross | cross- on |
High Tide / height (m) | 10:34AM 1.31 | 10:08PM 1.05 | 11:23AM 1.30 | 12:13AM 1.02 | 12:10PM 1.31 | |||||||||||||||||||
Low Tide / height (m) | 3:23AM 0.49 | 5:20PM 0.82 | 4:28AM 0.64 | 6:38PM 0.67 | 5:45AM 0.78 | 7:37PM 0.51 | ||||||||||||||||||
Friday 12 | Saturday 13 | Sunday 14 | ||||||||||||||||||||||
| Sunrise | - | - | - | 6:39 | - | - | - | - | - | - | - | 6:41 | - | - | - | - | - | - | - | 6:41 | - | - | - | - |
| Sunset | - | - | - | - | - | 4:30 | - | - | - | - | - | - | - | 4:30 | - | - | - | - | - | - | - | 4:30 | - | - |
 | |  |  |  | | | | |  | | | | |  | | | | |  | | | | | |
Rain (mm) | - | - | - | - | - | - | - | - | - | - | - | - | - | - | 2 | 1 | - | - | 3 | 2 | 4 | - | - | - |
| Temp. °C | 14 | 11 | 7 | 7 | 9 | 9 | 8 | 7 | 6 | 5 | 5 | 4 | 6 | 6 | 5 | 5 | 5 | 5 | 6 | 6 | 8 | 10 | 12 | 12 |
| Feels °C (?) | 5 | 4 | -4 | -2 | 1 | 1 | 1 | 1 | 1 | -1 | -1 | -2 | 2 | 1 | 0 | -1 | -1 | -1 | 1 | 0 | 3 | 8 | 7 | 7 |
- 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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