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 8 am Sunday 14 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
18.5° C
(Which is slightly cooler than normal)How big are the waves at Kugenuma Rivermouth today?
The current surf forecast for Kugenuma Rivermouth at 11AM is: 0.8m 7s primary swell from a South-southeast direction (forecast issued at 08:00am December 14). An open ocean swell of 0.4m 3s is not directed at the surf break. The wind direction is predicted to be offshore.
| Time (JST) & Date | Wave Height | Wave Period |
|---|---|---|
| Morning (14 Dec) | 2ft (0.6m) | 7s |
| Afternoon (14 Dec) | 6ft (1.9m) | 10s |
| Evening (14 Dec) | 6ft (1.9m) | 9s |
Table - waves today at Kugenuma Rivermouth. (Swell directed towards the surf break)
Updates in hr min s Forecast update imminent
Sunday 14 | Monday 15 | Tuesday 16 | Wed 17 | |||||||||||||||||||||
| 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 | 0 AM | 3 AM | |
Rating (10 max) | ||||||||||||||||||||||||
Swell Height Map |    |    |    |    | ||||||||||||||||||||
| Wave Height (m) & direction (?) | ||||||||||||||||||||||||
| Period(s) (?) | 6 | 7 | 8 | 10 | 8 | 9 | 8 | 9 | 9 | 10 | 9 | 9 | 9 | 9 | 8 | 8 | 8 | 8 | 8 | 8 | 8 | 8 | 7 | 4 |
Wave (?)Graph  | ||||||||||||||||||||||||
 kJ (?) | 20 | 31 | 98 | 664 | 623 | 565 | 284 | 255 | 125 | 55 | 35 | 22 | 21 | 19 | 11 | 11 | 14 | 11 | 7 | 6 | 6 | 6 | 14 | 6 |
Wind (km/h) | ||||||||||||||||||||||||
| Wind State (?) onshore cross-onshore cross-shore cross-offshore offshore glassy | off | off | off | cross- on | cross- off | cross- on | cross | cross | cross- off | off | glass | cross- off | off | off | off | off | off | off | glass | cross- on | glass | glass | cross- off | cross- off |
High Tide / height (m) | 12:10PM 1.31 | 2:15AM 1.08 | 12:52PM 1.33 | 3:35AM 1.17 | 1:31PM 1.36 | |||||||||||||||||||
Low Tide / height (m) | 5:45AM 0.78 | 7:37PM 0.51 | 7:02AM 0.89 | 8:25PM 0.36 | 8:07AM 0.97 | 9:07PM 0.23 | ||||||||||||||||||
Sunday 14 | Monday 15 | Tuesday 16 | Wed 17 | |||||||||||||||||||||
| Sunrise | - | 6:41 | - | - | - | - | - | - | - | 6:41 | - | - | - | - | - | - | - | 6:43 | - | - | - | - | - | - |
| Sunset | - | - | - | 4:30 | - | - | - | - | - | - | - | 4:30 | - | - | - | - | - | - | - | 4:30 | - | - | - | - |
 |  |  |  |  | | | | |  | | | |  |  | | | | | | | | | | |
Rain (mm) | 5 | 16 | 18 | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - |
| Temp. °C | 5 | 6 | 8 | 11 | 12 | 12 | 11 | 10 | 9 | 10 | 12 | 13 | 11 | 10 | 9 | 8 | 7 | 7 | 9 | 10 | 11 | 10 | 10 | 9 |
| Feels °C (?) | -1 | -2 | 3 | 7 | 7 | 6 | 5 | 5 | 5 | 6 | 9 | 9 | 4 | 4 | 4 | 2 | 1 | 2 | 6 | 6 | 9 | 8 | 7 | 6 |
- 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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