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Surf Forecasts:
Rock Island surfForecast / Kanagawa / Japan
48hr Weather and Surf, issued 2 pm Tuesday 19 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
20.2° C
(Which is slightly cooler than normal)How big are the waves at Rock Island today?
The current surf forecast for Rock Island at 11PM is: 0.4m 11s primary swell from a Southeast direction and 0.8m 4s secondary swell from a South-southwest direction (forecast issued at 02:00pm May 19). The wind direction is predicted to be onshore.
| Time (JST) & Date | Wave Height | Wave Period |
|---|---|---|
| Morning (19 May) | - | - |
| Afternoon (19 May) | 3ft (0.9m) | 4s |
| Evening (19 May) | 3ft (0.9m) | 4s |
Table - waves today at Rock Island. (Swell directed towards the surf break)
Updates in hr min s Forecast update imminent
Short Range ForecastHeavy rain (total 45mm), heaviest during Thu night. Warm (max 23°C on Wed morning, min 14°C on Thu night). Winds increasing (calm on Thu morning, strong winds from the N by Fri morning). | ||||||||||||||||||||||||
Tue 19 | Wednesday 20 | Thursday 21 | Fri 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 | 12 AM | 3 AM | 6 AM | 9 AM | |
Swell Height Map |    |    |    |    | ||||||||||||||||||||
SE 11 | S 4 | S 4 | SSW 4 | SE 11 | SE 11 | SE 11 | SE 10 | SE 10 | SSW 4 | S 5 | SSW 5 | SE 10 | SE 9 | S 5 | S 6 | SSW 7 | SSW 8 | S 8 | S 8 | S 8 | S 8 | S 7 | S 8 | |
29 | 28 | 41 | 34 | 29 | 29 | 40 | 38 | 27 | 31 | 43 | 35 | 21 | 14 | 36 | 48 | 225 | 276 | 138 | 145 | 121 | 72 | 54 | 41 | |
Wind (km/h) | ||||||||||||||||||||||||
on | on | on | on | on | on | on | on | on | on | on | on | on | on | cross-on | glassy | cross-off | off | off | off | off | off | off | off | |
High Tide | 7:46PM1.35m | 5:44AM1.42m | 8:34PM1.32m | 6:22AM1.38m | 9:23PM1.28m | 7:05AM1.31m | ||||||||||||||||||
Low Tide | 12:29PM-0.09m | 00:37AM0.95m | 1:09PM-0.06m | 1:18AM0.98m | 1:53PM0.01m | 2:07AM0.99m | ||||||||||||||||||
 |  | |  |  | | | | | |  | |  | |  | | | |  | | |  | | | |
 | — | — | — | — | — | 4:33 | — | — | — | — | — | — | — | 4:33 | — | — | — | — | — | — | — | 4:33 | — | — |
 | — | — | 6:40 | — | — | — | — | — | — | — | 6:42 | — | — | — | — | — | — | — | 6:43 | — | — | — | — | 6:43 |
— | — | — | — | — | — | — | — | — | — | — | — | 1 | 1 | 2 | 1 | 4 | 4 | 7 | 5 | 5 | 13 | 1 | 1 | |
Temp °C | 22 | 22 | 21 | 21 | 20 | 20 | 20 | 21 | 23 | 23 | 23 | 22 | 22 | 21 | 21 | 21 | 19 | 18 | 16 | 15 | 14 | 14 | 14 | 14 |
18 | 17 | 16 | 18 | 18 | 19 | 19 | 20 | 21 | 20 | 21 | 21 | 21 | 21 | 22 | 24 | 18 | 16 | 11 | 10 | 9 | 9 | 7 | 5 | |
Swell 1 Height (m) Direction Period (s) | SE 11 | SE 11 | SE 11 | SE 11 | SE 11 | SE 11 | SE 11 | SE 10 | SE 10 | SE 10 | SE 10 | SE 10 | SE 10 | SE 9 | S 4 | S 6 | S 7 | S 7 | S 8 | S 8 | S 8 | S 8 | S 7 | S 8 |
 kJ | 29 | 18 | 18 | 18 | 29 | 29 | 40 | 38 | 27 | 16 | 15 | 15 | 14 | 14 | 9 | 48 | 107 | 155 | 138 | 145 | 121 | 72 | 54 | 41 |
Swell 2 Height (m) Direction Period (s) | ESE 9 | E 10 | — | — | — | — | — | SE 5 | — | — | — | — | — | S 7 | SE 9 | SE 10 | — | — | ESE 10 | ESE 10 | SE 9 | SE 9 | SE 9 | SE 9 |
| kJ | 16 | 8 | — | — | — | — | — | 7 | — | — | — | — | — | 1 | 14 | 14 | — | — | 10 | 36 | 3 | 3 | 3 | 3 |
Swell 3 Height (m) Direction Period (s) | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | SE 11 | SE 11 | SE 11 | E 11 |
| kJ | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 5 | 5 | 5 | 2 |
Wind waves Height (m) Direction Period (s) | S 4 | S 4 | S 4 | SSW 4 | SSW 4 | SSW 4 | SSW 4 | SSW 4 | S 4 | SSW 4 | S 5 | SSW 5 | SSW 4 | S 4 | S 5 | — | SSW 7 | SSW 8 | NNE 2 | NE 3 | NE 3 | NE 3 | NE 4 | NNE 4 |
| kJ | 9 | 28 | 41 | 34 | 20 | 11 | 6 | 5 | 10 | 31 | 43 | 35 | 21 | 9 | 36 | — | 225 | 276 | 1 | 2 | 5 | 6 | 12 | 17 |
Nearest Offshore or Glassy | ||||||||||||||||||||||||
Distance (km) | 77 | 518 | 491 | 90 | 38 | 38 | 38 | 142 | 491 | 491 | 90 | 38 | 38 | 38 | 38 | 0 | 10 | 0 | 228 | 104 | 38 | 487 | 487 | 488 |
Best forecast wave conditions in Kanagawa | ||||||||||||||||||||||||
Best forecast wave conditions in Japan | ||||||||||||||||||||||||
Header Global | ||||||||||||||||||||||||
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