- Forecast
- Maps
- Live
- Weather State
- Spot Information
Surf Forecasts:
Rock Island surfForecast / Kanagawa / Japan
48hr Weather and Surf, issued 2 pm Saturday 16 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
19.9° C
(Which is slightly cooler than normal)How big are the waves at Rock Island today?
The current surf forecast for Rock Island at 6PM is: 0.3m 7s primary swell from a Southeast direction and 0.1m 11s secondary swell from a Southeast direction, 0.3m 2s secondary swell from a South direction (forecast issued at 02:00pm May 16). The wind direction is predicted to be onshore.
| Time (JST) & Date | Wave Height | Wave Period |
|---|---|---|
| Morning (16 May) | - | - |
| Afternoon (16 May) | 1ft (0.3m) | 7s |
| Evening (16 May) | 1ft (0.3m) | 7s |
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 23°C on Sun morning, min 18°C on Sat night). Winds increasing (calm on Sun night, fresh winds from the S by Mon afternoon). | ||||||||||||||||||||||||
Sat 16 | Sunday 17 | Monday 18 | Tue 19 | |||||||||||||||||||||
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 |    |    |    |    | ||||||||||||||||||||
SE 7 | SE 7 | SE 7 | SE 7 | SE 7 | SE 7 | SE 7 | SE 11 | SE 8 | SE 8 | SE 10 | SE 8 | SE 8 | SE 8 | ESE 9 | SE 10 | SE 8 | SE 10 | SE 10 | SE 10 | SE 7 | SE 7 | SE 10 | SE 10 | |
9 | 8 | 8 | 8 | 12 | 8 | 8 | 19 | 10 | 10 | 17 | 10 | 11 | 10 | 7 | 15 | 17 | 16 | 24 | 16 | 12 | 10 | 16 | 17 | |
Wind (km/h) | ||||||||||||||||||||||||
glassy | on | on | on | cross-on | cross-on | glassy | off | cross-on | on | on | on | on | glassy | off | cross-on | on | on | on | on | on | on | on | on | |
High Tide | 5:29PM1.36m | 4:08AM1.40m | 6:15PM1.38m | 4:38AM1.42m | 7:00PM1.37m | 5:10AM1.43m | ||||||||||||||||||
Low Tide | 10:34AM0.05m | 10:46PM0.79m | 11:11AM-0.04m | 11:23PM0.86m | 11:49AM-0.09m | 11:59PM0.91m | ||||||||||||||||||
 | | |  |  | | | | | | | | | | | | | | | | | | | | |
 | — | — | — | — | — | 4:35 | — | — | — | — | — | — | — | 4:35 | — | — | — | — | — | — | — | 4:35 | — | — |
 | — | — | 6:38 | — | — | — | — | — | — | — | 6:38 | — | — | — | — | — | — | — | 6:39 | — | — | — | — | 6:40 |
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | |
Temp °C | 20 | 20 | 19 | 19 | 19 | 18 | 18 | 21 | 23 | 23 | 22 | 20 | 20 | 20 | 20 | 21 | 21 | 21 | 21 | 21 | 20 | 20 | 19 | 20 |
19 | 17 | 16 | 18 | 18 | 17 | 17 | 19 | 22 | 20 | 19 | 17 | 18 | 20 | 20 | 20 | 17 | 16 | 16 | 18 | 17 | 18 | 17 | 17 | |
Swell 1 Height (m) Direction Period (s) | SE 7 | SE 7 | SE 7 | SE 7 | SE 7 | SE 7 | SE 7 | SE 7 | SE 8 | SE 8 | SE 10 | SE 8 | SE 8 | SE 8 | ESE 9 | SE 10 | SE 8 | SE 8 | SE 8 | SE 7 | SE 7 | SE 7 | SE 10 | SE 10 |
 kJ | 9 | 8 | 8 | 8 | 12 | 8 | 8 | 8 | 10 | 10 | 15 | 10 | 11 | 10 | 7 | 15 | 10 | 10 | 9 | 9 | 8 | 8 | 16 | 17 |
Swell 2 Height (m) Direction Period (s) | SE 11 | SE 11 | SE 11 | SE 11 | SE 10 | SE 10 | SE 10 | SE 10 | SE 11 | SE 10 | SE 10 | SE 10 | SE 12 | S 3 | SE 7 | ESE 8 | SE 8 | SE 12 | SE 10 | SE 10 | SE 10 | ESE 10 | SSE 7 | ESE 9 |
| kJ | 5 | 5 | 5 | 4 | 4 | 4 | 4 | 4 | 4 | 4 | 17 | 4 | 5 | 1 | 2 | 6 | 17 | 5 | 4 | 4 | 4 | 10 | 5 | 17 |
Swell 3 Height (m) Direction Period (s) | — | S 6 | E 10 | SE 13 | SE 14 | SE 14 | — | SE 11 | — | — | — | — | — | SE 12 | SE 10 | — | SE 10 | SE 10 | SE 10 | SE 10 | SE 7 | SSE 7 | — | — |
| kJ | — | 1 | 2 | 7 | 7 | 7 | — | 19 | — | — | — | — | — | 5 | 4 | — | 17 | 16 | 24 | 16 | 12 | 5 | — | — |
Wind waves Height (m) Direction Period (s) | — | — | S 2 | S 3 | — | — | — | — | — | — | SSE 3 | S 3 | S 3 | WSW 2 | — | — | S 2 | S 3 | SSW 4 | SSW 4 | SSW 4 | SSW 3 | SW 3 | SSW 4 |
| kJ | — | — | 1 | 1 | — | — | — | — | — | — | 3 | 1 | 1 | 1 | — | — | 1 | 7 | 15 | 13 | 5 | 5 | 3 | 10 |
Nearest Offshore or Glassy | ||||||||||||||||||||||||
Distance (km) | 16 | 51 | 18 | 51 | 51 | 54 | 16 | 16 | 16 | 104 | 77 | 76 | 18 | 54 | 16 | 18 | 76 | 77 | 90 | 90 | 38 | 38 | 38 | 90 |
Best forecast wave conditions in Kanagawa | ||||||||||||||||||||||||
Best forecast wave conditions in Japan | ||||||||||||||||||||||||
Header Global | ||||||||||||||||||||||||
- Map Icons:
Break
Live Wave Height (m)
Live Wind Speed (km/h)
Surf Rating (10 Max)
Ocean Swells (m)- Wind Speed (km/h)
FREE! Surf-Forecast.com widget for your website
The surf report / weather widget below is available to embed on third party websites free of charge and provides a summary of our Rock Island surf forecast. Simply grab the html code snippet that we provide and paste it into your own site. You can choose your preferred language and metric/imperial units for the surf forecast feed to suit users of your site. Click here to get the code.
Nearest