Surf Forecasts:
How big are the waves at Rock Island today (20 Sep):
- Morning surf: Morning surf (20 Sep, local time) - 5.5ft (1.7m), 12s period with SSE swell.
- Afternoon surf: Afternoon surf (20 Sep, local time) - 5.5ft (1.7m), 12s period with SSE swell.
- Evening surf: Evening surf (20 Sep, local time) - 6ft (1.8m), 12s period with SSE swell.
The current surf forecast for Rock Island at 7AM is: 1.7m 12s primary swell from a South-southeast direction (forecast issued at 02:00am September 20). An open ocean swell of 0.5m 3s is not directed at the surf break. The wind direction is predicted to be offshore.
| Time (JST) & Date | Wave Height | Wave Period |
|---|---|---|
| Morning (20 Sep) | 5.5ft (1.7m) | 12s |
| Afternoon (20 Sep) | 5.5ft (1.7m) | 12s |
| Evening (20 Sep) | 6ft (1.8m) | 12s |
Table - waves today at Rock Island. (Swell directed towards the surf break)
Short Range ForecastHeavy rain (total 225mm), heaviest during Mon night. Warm (max 28°C on Tue afternoon, min 22°C on Sun morning). Mainly severe gales. | ||||||||||||||||||||||||
Sunday 20 | Monday 21 | Tuesday 22 | ||||||||||||||||||||||
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 | 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 13 | SSE 13 | SSE 12 | SSE 12 | SSE 12 | SSE 12 | SSE 12 | SSE 12 | SSE 12 | SSE 12 | S 12 | S 12 | S 12 | S 13 | S 13 | S 13 | S 15 | S 14 | SSE 12 | S 10 | S 10 | S 9 | S 9 | S 9 |
Wave Graph  | ||||||||||||||||||||||||
 kJ | 1134 | 983 | 871 | 830 | 802 | 723 | 805 | 902 | 969 | 1090 | 1312 | 1591 | 1881 | 2334 | 2920 | 5116 | 11495 | 6736 | 1302 | 562 | 384 | 288 | 194 | 146 |
Wind (km/h) | ||||||||||||||||||||||||
Wind State on-shore cross-onshore cross-shore cross-offshore off-shore glassy | off | off | off | off | off | off | off | off | off | off | off | off | off | off | off | cross-off | off | cross-off | cross | on | cross-on | cross | off | off |
High Tide | 1:35PM1.24m | 9:38PM1.34m | 2:52PM1.30m | 11:27PM1.28m | 3:27PM1.35m | |||||||||||||||||||
Low Tide | 4:55AM0.41m | 4:31PM1.21m | 6:20AM0.44m | 7:16PM1.19m | 7:40AM0.43m | 8:38PM1.08m | ||||||||||||||||||
 |  |  |  | | |  | | | | | | | |  | | | | |  | | | | | |
 | — | 5:26 | — | — | — | — | — | — | — | 5:28 | — | — | — | — | — | — | — | 5:28 | — | — | — | — | — | — |
 | — | — | — | — | — | 5:43 | — | — | — | — | — | — | — | 5:40 | — | — | — | — | — | — | — | 5:39 | — | — |
mm | — | 1 | 9 | 4 | 8 | 6 | 8 | 2 | 2 | 4 | 3 | 5 | 6 | 4 | 16 | 61 | 44 | 47 | 5 | — | — | — | — | — |
Temp °C | 23 | 23 | 23 | 23 | 22 | 22 | 22 | 22 | 22 | 22 | 22 | 22 | 22 | 23 | 23 | 25 | 25 | 24 | 26 | 26 | 27 | 27 | 28 | 26 |
Feels °C | 23 | 22 | 22 | 22 | 20 | 20 | 20 | 20 | 20 | 20 | 19 | 19 | 20 | 21 | 20 | 24 | 20 | 14 | 29 | 28 | 29 | 31 | 25 | 22 |
Swell 1 Height (m) Direction Period (s) | SSE 13 | SSE 13 | SSE 12 | SSE 12 | SSE 12 | SSE 12 | SSE 12 | SSE 12 | SSE 12 | SSE 12 | S 12 | S 12 | S 12 | S 13 | S 13 | S 13 | S 15 | S 14 | SSE 12 | S 10 | S 10 | S 9 | S 9 | S 9 |
| kJ | 1134 | 983 | 871 | 830 | 802 | 723 | 805 | 902 | 969 | 1090 | 1312 | 1591 | 1881 | 2334 | 2920 | 5116 | 11495 | 6736 | 1302 | 562 | 384 | 288 | 194 | 146 |
Swell 2 Height (m) Direction Period (s) | — | — | — | — | E 14 | S 15 | — | — | — | E 12 | E 12 | E 11 | E 11 | SSE 11 | S 13 | — | — | — | NNW 5 | NNW 5 | SSW 9 | — | SSW 8 | SSW 8 |
| kJ | — | — | — | — | 4 | 153 | — | — | — | 12 | 11 | 10 | 9 | 1733 | 2364 | — | — | — | 25 | 5 | 292 | — | 137 | 76 |
Swell 3 Height (m) Direction Period (s) | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | NNW 6 | SSW 12 | — | — | — | — |
| kJ | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 56 | 14 | — | — | — | — |
Wind waves Height (m) Direction Period (s) | NNE 3 | NNE 3 | NNE 3 | NNE 3 | NNE 3 | NNE 3 | N 3 | NNE 3 | NNE 3 | NNE 3 | NNE 3 | N 3 | N 3 | N 3 | NNE 3 | — | NE 5 | N 6 | SW 10 | — | — | — | N 2 | NE 3 |
| kJ | 4 | 5 | 5 | 5 | 7 | 5 | 5 | 5 | 8 | 6 | 5 | 5 | 7 | 11 | 9 | — | 141 | 256 | 184 | — | — | — | 1 | 5 |
Nearest Offshore or Glassy | ||||||||||||||||||||||||
Distance (km) | 0 | 38 | 488 | 552 | 552 | 552 | 552 | 552 | 565 | 51 | 51 | 38 | 38 | 510 | 509 | 488 | 487 | 487 | 10 | 27 | 64 | 12 | 8 | 38 |
Best forecast wave conditions in Kanagawa | ||||||||||||||||||||||||
Best forecast wave conditions in Japan | ||||||||||||||||||||||||
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