Surf Forecasts:
How big are the waves at Rock Island today (20 Aug):
- Afternoon surf: Afternoon surf (20 Aug, local time) - 0.5ft (0.2m), 9s period with SSW swell.
- Evening surf: Evening surf (20 Aug, local time) - 0.5ft (0.2m), 8s period with SSW swell.
The current surf forecast for Rock Island at 7PM is: 0.2m 9s primary swell from a South-southwest direction and 0.1m 11s secondary swell from a Southeast direction, 0.4m 3s secondary swell from a South-southeast direction (forecast issued at 02:00pm August 20). The wind direction is predicted to be onshore.
| Time (JST) & Date | Wave Height | Wave Period |
|---|---|---|
| Morning (20 Aug) | - | - |
| Afternoon (20 Aug) | 0.5ft (0.2m) | 9s |
| Evening (20 Aug) | 0.5ft (0.2m) | 8s |
Table - waves today at Rock Island. (Swell directed towards the surf break)
Short Range ForecastModerate rain (total 10mm), heaviest on Sat night. Warm (max 27°C on Thu afternoon, min 24°C on Sat night). Winds decreasing (fresh winds from the S on Fri afternoon, calm by Sat morning). | ||||||||||||||||||||
Thu 20 | Friday 21 | Saturday 22 | ||||||||||||||||||
12 PM | 3 PM | 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) | SSE 6 | SSW 9 | SSW 9 | SSW 8 | S 10 | SSW 9 | SSW 9 | SSW 9 | S 9 | S 9 | SSW 4 | SSW 9 | SSW 9 | SSW 10 | SSW 9 | SSW 9 | SSW 9 | SSW 9 | SSW 9 | SSW 9 |
Wave Graph  | ||||||||||||||||||||
 kJ | 4 | 8 | 8 | 7 | 8 | 25 | 27 | 27 | 78 | 101 | 27 | 106 | 35 | 36 | 34 | 32 | 32 | 32 | 32 | 32 |
Wind (km/h) | ||||||||||||||||||||
Wind State on-shore cross-onshore cross-shore cross-offshore off-shore glassy | on | on | on | on | on | on | on | on | on | on | on | on | on | on | cross-on | glassy | on | on | cross-on | cross-on |
High Tide | 9:59AM1.24m | 9:00PM1.45m | 11:32AM1.17m | 9:36PM1.42m | 1:55PM1.18m | |||||||||||||||
Low Tide | 3:00PM0.90m | 4:23AM0.44m | 3:34PM1.04m | 5:36AM0.43m | 4:30PM1.15m | |||||||||||||||
 |  | |  |  | |  | | | | | | | | | | | | |  | |
 | — | — | — | — | — | 5:05 | — | — | — | — | — | — | — | 5:05 | — | — | — | — | — | — |
 | — | — | 6:24 | — | — | — | — | — | — | — | 6:23 | — | — | — | — | — | — | — | 6:22 | — |
mm | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 3 |
Temp °C | 27 | 27 | 27 | 26 | 26 | 26 | 26 | 26 | 27 | 27 | 27 | 26 | 26 | 26 | 26 | 27 | 27 | 27 | 27 | 27 |
Feels °C | 29 | 28 | 29 | 27 | 28 | 28 | 29 | 29 | 28 | 27 | 27 | 26 | 26 | 28 | 29 | 31 | 29 | 29 | 29 | 31 |
Swell 1 Height (m) Direction Period (s) | SSE 6 | SSW 9 | SSW 9 | SSW 8 | SSW 8 | SSW 9 | SSW 9 | SSW 9 | SE 11 | SE 11 | SE 11 | SE 10 | SSW 9 | SSW 10 | SSW 9 | SSW 9 | SSW 9 | SSW 9 | SSW 9 | SSW 9 |
| kJ | 3 | 8 | 8 | 7 | 6 | 25 | 27 | 27 | 4 | 4 | 4 | 4 | 35 | 36 | 34 | 32 | 32 | 32 | 32 | 32 |
Swell 2 Height (m) Direction Period (s) | SE 11 | SE 11 | SE 11 | SE 11 | S 10 | SE 11 | SE 11 | SE 11 | S 9 | S 9 | S 9 | S 9 | SE 10 | SE 10 | SE 10 | S 4 | SSE 5 | SE 10 | SE 10 | SE 10 |
| kJ | 4 | 4 | 4 | 4 | 8 | 4 | 4 | 4 | 2 | 2 | 2 | 2 | 4 | 4 | 4 | 6 | 2 | 4 | 4 | 4 |
Swell 3 Height (m) Direction Period (s) | S 9 | E 6 | E 6 | SE 6 | SE 11 | SE 5 | SE 5 | SE 5 | E 10 | S 13 | SE 6 | S 9 | S 9 | S 9 | SE 11 | SE 10 | SE 10 | SE 11 | SE 11 | SE 11 |
| kJ | 2 | 1 | 1 | 1 | 4 | 1 | 1 | 4 | 7 | 3 | 1 | 2 | 2 | 2 | 4 | 4 | 4 | 5 | 5 | 5 |
Wind waves Height (m) Direction Period (s) | — | SSE 2 | SSE 3 | S 3 | SSW 3 | SSW 3 | SSW 3 | SSW 3 | S 9 | S 9 | SSW 4 | SSW 9 | SSW 4 | S 4 | SSW 4 | — | SSW 4 | S 5 | S 4 | S 4 |
| kJ | — | 1 | 2 | 1 | 3 | 2 | 2 | 2 | 78 | 101 | 27 | 106 | 11 | 7 | 5 | — | 3 | 10 | 9 | 7 |
Nearest Offshore or Glassy | ||||||||||||||||||||
Distance (km) | 77 | 76 | 76 | 76 | 76 | 76 | 76 | 76 | 77 | 77 | 92 | 27 | 90 | 38 | 18 | 18 | 77 | 77 | 76 | 72 |
Best forecast wave conditions in Kanagawa | ||||||||||||||||||||
Best forecast wave conditions in Japan | ||||||||||||||||||||
Header Global | ||||||||||||||||||||
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