Surf Forecasts:
How big are the waves at Rock Island today (21 Aug):
- Evening surf: Evening surf (21 Aug, local time) - 1.5ft (0.4m), 9s period with SSW swell.
The current surf forecast for Rock Island at 11PM is: 0.4m 9s primary swell from a South-southwest direction and 0.1m 10s secondary swell from a Southeast direction, 0.6m 4s secondary swell from a South-southwest direction (forecast issued at 08:00pm August 21). The wind direction is predicted to be onshore.
| Time (JST) & Date | Wave Height | Wave Period |
|---|---|---|
| Morning (21 Aug) | - | - |
| Afternoon (21 Aug) | - | - |
| Evening (21 Aug) | 1.5ft (0.4m) | 9s |
Table - waves today at Rock Island. (Swell directed towards the surf break)
Short Range ForecastModerate rain (total 14mm), heaviest on Sat night. Warm (max 28°C on Sat morning, min 24°C on Sat night). Wind will be generally light. | ||||||||||||||||||
Fri 21 | Saturday 22 | Sunday 23 | ||||||||||||||||
6 PM | 9 PM | 12 AM | 3 AM | 6 AM | 9 AM | 12 PM | 3 PM | 6 PM | 9 PM | 12 AM | 3 AM | 6 AM | 9 AM | 12 PM | 3 PM | 6 PM | 9 PM | |
Swell Height Map |  |  |  |  |  |  |  | |||||||||||
Wave Height (m) Direction Period (s) | S 9 | SSW 9 | SSW 9 | SSW 10 | SSW 9 | SSW 9 | SSW 9 | SSW 9 | SSW 9 | SSW 9 | SSW 9 | SW 9 | SSW 9 | SSW 9 | SSW 8 | SE 13 | SE 12 | SE 12 |
Wave Graph  | ||||||||||||||||||
 kJ | 101 | 26 | 35 | 36 | 34 | 32 | 32 | 32 | 32 | 32 | 31 | 20 | 26 | 25 | 24 | 27 | 23 | 38 |
Wind (km/h) | ||||||||||||||||||
Wind State on-shore cross-onshore cross-shore cross-offshore off-shore glassy | on | on | on | on | cross-on | cross-on | cross-on | on | cross-on | cross-off | cross-off | off | off | off | cross-off | cross-on | on | on |
High Tide | 9:36PM1.42m | 1:55PM1.18m | 10:25PM1.38m | 3:38PM1.26m | ||||||||||||||
Low Tide | 3:34PM1.04m | 5:36AM0.43m | 4:30PM1.15m | 6:58AM0.39m | 6:54PM1.21m | |||||||||||||
 |  | |  |  | | | |  |  | |  |  | | | | | | |
 | — | — | — | 5:05 | — | — | — | — | — | — | — | 5:05 | — | — | — | — | — | — |
 | 6:23 | — | — | — | — | — | — | — | 6:22 | — | — | — | — | — | — | — | 6:22 | — |
mm | — | — | — | — | — | — | — | — | — | 2 | 6 | 3 | 2 | 1 | — | — | — | — |
Temp °C | 27 | 27 | 26 | 26 | 26 | 27 | 28 | 28 | 28 | 27 | 26 | 24 | 24 | 25 | 27 | 28 | 27 | 26 |
Feels °C | 27 | 28 | 27 | 28 | 29 | 31 | 31 | 31 | 32 | 30 | 29 | 26 | 25 | 26 | 28 | 30 | 30 | 29 |
Swell 1 Height (m) Direction Period (s) | SE 11 | SSW 9 | SSW 9 | SSW 10 | SSW 9 | SSW 9 | SSW 9 | SSW 9 | SSW 9 | SSW 9 | SSW 9 | SW 9 | SSW 9 | SSW 9 | SSW 8 | SSW 8 | SSW 8 | SE 12 |
| kJ | 4 | 26 | 35 | 36 | 34 | 32 | 32 | 32 | 32 | 32 | 31 | 20 | 26 | 25 | 24 | 14 | 23 | 38 |
Swell 2 Height (m) Direction Period (s) | S 9 | SE 10 | SE 10 | SE 10 | SE 10 | S 4 | SE 10 | SE 10 | SE 10 | SE 10 | SE 10 | S 5 | SSE 10 | SE 10 | SSE 13 | SE 13 | SE 12 | SSW 8 |
| kJ | 2 | 4 | 4 | 4 | 4 | 3 | 4 | 4 | 4 | 4 | 4 | 4 | 10 | 4 | 17 | 27 | 23 | 14 |
Swell 3 Height (m) Direction Period (s) | — | S 9 | S 9 | S 9 | SE 11 | SE 10 | SE 11 | SE 11 | SE 11 | SE 11 | SE 11 | SSE 10 | SE 11 | SE 13 | SSE 10 | SSE 4 | SSE 14 | SSE 10 |
| kJ | — | 2 | 2 | 2 | 4 | 4 | 5 | 5 | 5 | 5 | 5 | 10 | 5 | 7 | 9 | 2 | 20 | 9 |
Wind waves Height (m) Direction Period (s) | S 9 | S 4 | SSW 4 | S 4 | SSW 4 | S 5 | S 5 | S 5 | S 5 | S 5 | S 5 | SSW 5 | — | — | — | SE 4 | — | — |
| kJ | 101 | 10 | 8 | 7 | 5 | 10 | 4 | 7 | 7 | 7 | 7 | 7 | — | — | — | 3 | — | — |
Nearest Offshore or Glassy | ||||||||||||||||||
Distance (km) | 92 | 92 | 77 | 38 | 38 | 18 | 18 | 76 | 38 | 55 | 55 | 16 | 51 | 51 | 0 | 16 | 18 | 16 |
Best forecast wave conditions in Kanagawa | ||||||||||||||||||
Best forecast wave conditions in Japan | ||||||||||||||||||
Header Global | ||||||||||||||||||
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Live Wave Height (m)
Live Wind Speed (km/h)
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Ocean Swells (m)- Wind Speed (km/h)
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