Rock Island Surf Break

Rock Island Surf Forecast and Surf Report

Lat Long: 35.29° N 139.55° E

Issued: 8 pm 02 Jul 2026 (local time)

Forecast update in  hr  min

Today's Rock Island sea temperature is
23.3° C

Slightly cooler than normal

Rock Island surf forecast is for near shore open water. Breaking waves will often be smaller at less exposed spots.


Rock Island surf forecast from 2 Jul 2026:

  • Best quality surf: Tuesday 7 Jul, 9AM (local time) - 4ft (1.2m), 17s period, SSE swell with glassy winds.
  • Most powerful swell: Friday 10 Jul, 3AM (local time) - 7.5ft (2.3m), 17s period, S swell with 2,880 kJ wave energy.
  • Next surfable swell (1★+): Tuesday 7 Jul, 12AM (local time) - 2.5ft (0.7m), 16s period with SE swell.

Best Forecast Surf Conditions for Rock Island this week:

The surf forecast for Rock Island over the next 16 days: The first swell (rated 1 star or higher) is forecast to arrive on Tuesday (Jul 07) at 12AM. The primary swell is predicted to be 0.7m and 16s period with a secondary swell of 0.5m and 7s. The wind is predicted to be glassy as the swell arrives.

The most powerful waves expected at Rock Island in the next 16 days are 2.3m 17s and forecast to arrive on Friday (Jul 10) at 3AM. Winds are predicted to be cross-onshore at the time the swell arrives.

Wave TypeTime (JST) & Date Wave Height & Period
Next good surf (1 star+)12AM (Tue 7th Jul)2.5ft (0.7m) 16s
Best Surf 9AM (Tue 7th Jul)4ft (1.2m) 17s
Most Powerful 3AM (Fri 10th Jul)7.5ft (2.3m) 17s

Table - best surf conditions forecast for Rock Island over the next 16 days.


Updates in  hr  min  s Forecast update imminent

Alright folks, Rusty here. Let's have a look at what's coming down the pipe for Rock Island.

Right off the bat, the first week is a bit of a write-off. We've got a long dry spell with tiny, weak swells and mostly onshore or cross-onshore winds. Through Friday the 3rd, Saturday, Sunday, and all the way into Monday the 6th, it's pretty much flat or just messy. The combined swell energy is barely a whisper, reading 34 to just over 100 (106), which feels like a lake. Not worth paddling out for.

Then things change on Tuesday the 7th. That morning glass-off is a beauty – clear skies, no wind, the water's glassy. A new south-southeast groundswell pushes in at about 4ft, with a very long period of 17 seconds and a combined energy reading of 754. That's proper moderate energy. The water temp is about average for this time of year, so nothing wild there. The problem? The optimum swell direction for Rock Island is from the south, and this is coming from the south-southeast, so it's not a perfect match. Still, that clean, glassy morning with a long-period groundswell will offer some fun ones, especially for the more skilled crew, though the long period can make it a bit straight at a reef.

The real standout, the one I'm getting a little excited about, is Friday the 10th. It's a week away, so treat it as promising, not locked in. But look at this – Friday morning is glassy, dead calm, with a solid 8ft south groundswell, a very long 18-second period, and combined energy hitting 3903. That's strong. That's a proper swell direction for the reef, and it's clean. This is "excellent surf conditions for experienced surfers" – that 8ft is big and powerful, not for beginners or the faint of heart. It'll be a paddling mission with those long-set gaps, but for the experts, this could be the session of the outlook. Friday afternoon the wind swings onshore, so the morning window is everything.

The swell drops after that. We get some okay leftovers on Saturday the 11th and Sunday the 12th, but the winds turn a bit messy. By the second week, from the 13th onward, it's back to small, weak, and mostly poor. There's a little glimmer on Friday the 17th with some clean cross-off winds and a small 1.5ft south-southwest swell, but the energy is low (73), so it's a tiny wave for a small board or a longboard.

Overall, the play is patience. There's one absolute gem on the morning of Friday the 10th, and a decent Tuesday morning on the 7th. Everything else is a desert.

Short Range Forecast

Light rain (total 3mm), mostly falling on Thu night. Warm (max 24°C on Sun morning, min 21°C on Thu night). Wind will be generally light.

Days 5-7 Weather Summary

Light rain (total 3mm), mostly falling on Sun night. Warm (max 24°C on Mon morning, min 22°C on Sun night). Wind will be generally light.

Friday
3
Saturday
4
Sunday
5
Monday
6
Tuesday
7
Wednesday
8
Thu
9
Night
AM
PM
Night
AM
PM
Night
AM
PM
Night
AM
PM
Night
AM
PM
Night
AM
PM
Night
AM
PM
Rating
(10 max)
1
0
0
0
0
0
0
0
0
0
0
0
2
3
1
3
1
0
1
1
0
Swell
Height Map
Height Map
Height Map
Height Map
Height Map
Height Map
Height Map
Height Map
Height Map
Wave
Height (m)
Direction
Period (s)
0.8
SSW
8
0.5
S
7
0.4
S
6
0.3
S
6
0.2
S
5
0.3
S
5
0.1
SE
10
0.4
SSE
4
0.7
SSE
5
0.5
SSE
6
0.4
SE
14
0.4
SE
13
0.7
SE
16
1.2
SSE
17
1.4
SSE
16
1.5
SSE
16
1.8
SSE
16
1.7
SSE
16
1.8
SSE
16
1.8
S
16
2.2
S
17
Wave Graph
Metric surfscale
Energy kJ
75
21
12
6
3
5
4
6
19
18
53
44
278
735
969
1027
1718
1376
1750
1589
2873
Wind (km/h)
20
NNE
15
NE
5
WNW
5
E
5
SE
15
SSW
10
SSE
5
ENE
15
S
10
SE
10
SE
15
SSW
5
SE
5
ESE
15
SSW
10
S
15
S
20
S
20
SSW
20
SSW
25
SSW
Wind State
off
off
glassy
cross-off
glassy
on
cross-on
cross-off
cross-on
cross-on
cross
on
glassy
glassy
on
cross-on
cross-on
on
on
on
on
High Tide
5:59AM1.46m
8:16PM1.41m
6:47AM1.42m
8:47PM1.39m
7:39AM1.35m
9:18PM1.38m
8:36AM1.27m
9:50PM1.36m
9:44AM1.18m
10:23PM1.35m
11:09AM1.11m
11:00PM1.35m
12:55PM1.10m
Low Tide
00:47AM0.96m
1:10PM0.05m
1:30AM0.90m
1:49PM0.16m
2:15AM0.83m
2:27PM0.29m
3:05AM0.76m
3:07PM0.44m
4:01AM0.69m
3:48PM0.60m
5:04AM0.60m
4:34PM0.76m
6:12AM0.50m
5:31PM0.91m
light rain
cloud
part cloud
part cloud
cloud
light rain
part cloud
rain showers
part cloud
light rain
part cloud
light rain
clear
clear
clear
part cloud
clear
clear
clear
clear
clear
<span class="translation_missing" title="translation missing: en.weather_tables.sunrise">Sunrise</span>
4:31
4:31
4:31
4:31
4:33
4:33
4:33
<span class="translation_missing" title="translation missing: en.weather_tables.sunset">Sunset</span>
7:00
7:00
7:00
7:00
7:00
6:59
6:59
6:59
 mm
1
1
1
2
1
Temp °C
21
22
23
22
23
22
22
24
24
23
24
23
22
24
24
23
24
24
23
25
27
Feels °C
20
23
25
24
25
23
23
25
24
23
25
23
24
25
23
24
23
23
22
23
26
Swell 1
Height (m)
Direction
Period (s)
0.8
SSW
8
0.5
S
7
0.4
S
6
0.3
S
6
0.2
S
5
0.1
SE
9
0.1
SE
10
0.1
SE
10
0.3
SSE
4
0.5
SSE
6
0.4
SSE
6
0.4
SE
13
0.7
SE
16
1.2
SSE
17
1.4
SSE
16
1.5
SSE
16
1.8
SSE
16
1.7
SSE
16
1.8
SSE
16
1.8
S
16
2.2
S
17
Energy kJ
75
21
12
6
2
3
4
4
4
18
15
44
278
735
969
1027
1718
1376
1750
1589
2873
Swell 2
Height (m)
Direction
Period (s)
0.1
SE
9
0.3
SW
8
0.2
SSW
7
0.2
SSW
6
0.1
SE
9
0.1
S
6
0.1
S
5
0.2
S
4
0.1
SE
10
0.1
SE
15
0.4
SE
14
0.2
SSE
18
0.5
SE
7
0.4
SSE
7
0.5
SSE
20
1
SSE
18
0.5
S
21
0.8
S
19
0.6
S
21
1.1
S
20
0.6
SSW
22
Energy kJ
3
10
5
4
3
1
1
1
4
9
53
31
24
19
237
724
218
470
314
910
366
Swell 3
Height (m)
Direction
Period (s)
0.1
E
12
0.1
SE
9
0.1
SE
9
0.1
SE
9
0.1
SW
6
0.1
SW
6
0.2
SSE
10
0.1
SE
9
0.1
SE
9
0.1
S
7
0.1
S
7
0.4
SE
7
Energy kJ
3
3
3
3
2
1
10
3
3
1
1
12
Wind waves
Height (m)
Direction
Period (s)
0.3
NNE
2
0.3
S
5
0.3
S
3
0.4
SSE
4
0.7
SSE
5
0.6
SSE
7
1
S
4
0.8
S
4
1
S
4
Energy kJ
1
5
2
6
19
30
35
24
36
Nearest Offshore or Glassy
Rating
(10 max)
1
1
1
1
1
1
1
1
1
1
1
1
2
3
4
4
4
4
4
4
9
Distance (km)
0
38
16
61
843
76
76
77
552
38
12
14
0
0
64
14
64
64
14
90
491
Best forecast wave conditions in Kanagawa
Rating
(10 max)
1
1
1
1
1
2
4
4
4
Best forecast wave conditions in Japan
Rating
(10 max)
2
2
1
1
1
1
1
1
1
1
2
2
4
4
4
5
4
6
8
8
9
Header Global
Rating
(10 max)
5
9
5
9
5
7
5
5
9
7
7
6
9
8
6
6
7
9
7
7
9
  • Map Icons:
  • Break
  • Live Wave Height (m)
  • Live Wind Speed (km/h)
  • Surf Rating (10 Max)
  • Ocean Swells (m)
  • Wind Speed (km/h)
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Information about the Rock Island Surf forecast

The above surf forecast table for Rock Island provides essential information for determining whether the surfing conditions will be good over the next 16 days. A general guide to surfing at Rock Island can be found by selecting the local surf guide option on the grey menu. Our Rock Island surf forecast is unique since it includes wave energy (power) that defines the real feel of the surf rather than just the height or the period. If you surf the same spot (Rock Island) regularly then make a mental note of the wave energy from the surf forecast table each time you go. Very soon you may start to choose your surf days based on the wave energy alone combined with our forecast of favourable offshore wind conditions. Our star ratings will help here and of course you will also find the usual wave height and period predictions on our surf forecasts as well as a full break down of the swell components under our advanced users option (to reveal that, click the little Einstein character under the tide times).

Further information to help with frequently asked questions about our surf forecast for Rock Island may be found under the help tab on the top menu and also by moving your mouse over the question marks on the surf forecast table itself. Please always bear in mind that the forecast is for near-shore open water and local factors at each surf break influence the actual breaking wave height, such as the beach / reef profile, water depths offshore and shelter.

Rock Island is 3 km (2 miles) from the city of Kamakura. If you plan a holiday in Kanagawa, look for hotels and other accommodation in Kamakura. Kamakura has rooms for a wide range of budgets as well as car hire and transport links.

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