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Surf Forecasts:
Rock Island surfForecast / Kanagawa / Japan
48hr Weather and Surf, issued 2 pm Saturday 30 May 2026 JSTForecast update in hr min s Forecast update imminent
Rock Island surf forecast is for near shore open water. Breaking waves will often be smaller at less exposed spots.
Today's Rock Island sea temperature is
20.8° C
(Which is slightly cooler than normal)How big are the waves at Rock Island today (30 May):
- Afternoon surf: Afternoon surf (30 May, local time) - 2ft (0.6m), 6s period with S swell.
- Evening surf: Evening surf (30 May, local time) - 1.5ft (0.5m), 4s period with S swell.
The current surf forecast for Rock Island at 8PM is: 0.6m 4s primary swell from a South direction and 0.2m 6s secondary swell from a South-southeast direction, 0.2m 6s secondary swell from a South-southwest direction (forecast issued at 02:00pm May 30). The wind direction is predicted to be onshore.
| Time (JST) & Date | Wave Height | Wave Period |
|---|---|---|
| Morning (30 May) | - | - |
| Afternoon (30 May) | 2ft (0.6m) | 6s |
| Evening (30 May) | 1.5ft (0.5m) | 4s |
Table - waves today at Rock Island. (Swell directed towards the surf break)
Updates in hr min s Forecast update imminent
Short Range ForecastMostly dry. Warm (max 25°C on Sun morning, min 20°C on Sun night). Winds decreasing (fresh winds from the S on Sat afternoon, calm by Sun morning). | ||||||||||||||||||||||||
Sat 30 | Sunday 31 | Monday 1 | Tue 2 | |||||||||||||||||||||
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 | 12 AM | 3 AM | 6 AM | 9 AM | |
Swell Height Map |    |    |    |    | ||||||||||||||||||||
S 7 | S 6 | S 4 | S 4 | SSE 6 | SSE 6 | S 15 | S 15 | S 13 | S 13 | S 12 | S 12 | S 12 | S 11 | S 11 | S 11 | SW 17 | SSW 16 | S 13 | SSW 14 | SSW 14 | SSW 14 | SSW 14 | SSW 14 | |
22 | 30 | 12 | 6 | 8 | 7 | 18 | 39 | 31 | 81 | 108 | 100 | 98 | 125 | 88 | 86 | 85 | 198 | 163 | 371 | 394 | 367 | 367 | 352 | |
Wind (km/h) | ||||||||||||||||||||||||
on | on | cross-on | on | cross-on | glassy | off | off | glassy | on | on | on | on | on | cross-on | glassy | on | on | on | on | on | on | on | on | |
High Tide | 5:08PM1.33m | 3:31AM1.41m | 5:55PM1.37m | 4:05AM1.44m | 6:40PM1.39m | 4:40AM1.45m | ||||||||||||||||||
Low Tide | 10:04AM0.08m | 10:12PM0.88m | 10:43AM-0.02m | 10:53PM0.93m | 11:23AM-0.08m | 11:32PM0.97m | ||||||||||||||||||
 | |  |  | | |  | | | | |  | | | | | | | | | | | | | |
 | — | — | — | — | — | 4:28 | — | — | — | — | — | — | — | 4:28 | — | — | — | — | — | — | — | 4:28 | — | — |
 | — | — | 6:49 | — | — | — | — | — | — | — | 6:50 | — | — | — | — | — | — | — | 6:50 | — | — | — | — | 6:51 |
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | |
Temp °C | 23 | 23 | 22 | 22 | 21 | 22 | 21 | 24 | 25 | 25 | 25 | 23 | 21 | 20 | 21 | 23 | 23 | 22 | 21 | 21 | 21 | 20 | 20 | 21 |
19 | 19 | 19 | 20 | 21 | 23 | 21 | 24 | 26 | 24 | 24 | 21 | 19 | 20 | 21 | 23 | 21 | 19 | 17 | 18 | 19 | 17 | 18 | 18 | |
Swell 1 Height (m) Direction Period (s) | SE 12 | SE 12 | SE 12 | SSE 6 | SSW 3 | SSE 6 | SSE 6 | SSE 6 | SSE 6 | S 13 | S 12 | S 12 | S 12 | SSW 6 | S 6 | S 6 | S 11 | SSW 16 | S 13 | SSW 14 | SSW 14 | SSW 14 | SSW 14 | SSW 14 |
 kJ | 5 | 5 | 6 | 4 | 2 | 7 | 7 | 7 | 6 | 81 | 108 | 100 | 98 | 43 | 34 | 23 | 85 | 198 | 163 | 371 | 394 | 367 | 367 | 352 |
Swell 2 Height (m) Direction Period (s) | S 13 | S 13 | E 9 | SSW 6 | SSE 6 | SSW 3 | S 15 | S 15 | S 13 | SSE 6 | SSE 6 | SSW 14 | SE 12 | S 11 | S 11 | S 11 | SW 17 | S 10 | SSW 15 | SE 11 | SE 11 | SE 11 | SE 11 | SE 11 |
| kJ | 3 | 3 | 2 | 4 | 8 | 1 | 18 | 39 | 31 | 6 | 3 | 39 | 5 | 125 | 88 | 86 | 70 | 48 | 135 | 5 | 5 | 5 | 5 | 5 |
Swell 3 Height (m) Direction Period (s) | ESE 6 | SE 6 | SE 13 | SE 12 | SE 11 | SE 11 | SE 11 | SE 12 | SSW 15 | SE 12 | SE 12 | SE 12 | SE 11 | S 18 | SSW 17 | SSW 14 | SSW 14 | SE 11 | SE 11 | SE 11 | SE 11 | SE 11 | SE 12 | S 15 |
| kJ | 12 | 10 | 7 | 6 | 5 | 5 | 5 | 6 | 22 | 6 | 6 | 5 | 20 | 6 | 29 | 39 | 36 | 5 | 5 | 19 | 30 | 20 | 21 | 4 |
Wind waves Height (m) Direction Period (s) | S 7 | S 6 | S 4 | S 4 | SW 3 | — | — | — | — | — | SSW 3 | SSW 4 | SSW 5 | SSW 6 | SSW 6 | — | S 5 | S 4 | SSW 4 | SSW 4 | SSW 4 | SSW 4 | SSW 4 | SSW 3 |
| kJ | 22 | 30 | 12 | 6 | 2 | — | — | — | — | — | 3 | 12 | 38 | 79 | 59 | — | 14 | 12 | 18 | 18 | 9 | 12 | 7 | 4 |
Nearest Offshore or Glassy | ||||||||||||||||||||||||
Distance (km) | 64 | 77 | 76 | 76 | 76 | 16 | 16 | 0 | 0 | 18 | 14 | 14 | 14 | 14 | 10 | 0 | 77 | 77 | 92 | 27 | 14 | 27 | 14 | 77 |
Best forecast wave conditions in Kanagawa | ||||||||||||||||||||||||
Best forecast wave conditions in Japan | ||||||||||||||||||||||||
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