Onjuku Surf Break

Lat Long: 35.18° N 140.35° E

Onjuku Surf Forecast and Surf Report

Issued: 8 pm 25 Jul 2026 (local time)

Forecast update in  hr  min

Today's Onjuku sea temperature is
26.4° C
0.3° 

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


Onjuku surf forecast from 25 Jul 2026:

  • Best quality surf: Sunday 26 Jul, 3AM (local time) - 3ft (0.9m), 8s period, ENE swell with offshore winds.
  • Most powerful swell: Sunday 26 Jul, 6AM (local time) - 4ft (1.2m), 8s period, NE swell with 173 kJ wave energy.
  • Next surfable swell (1★+): Sunday 26 Jul, 3AM (local time) - 3ft (0.9m), 8s period with ENE swell.

Best Forecast Surf Conditions for Onjuku this week:

The surf forecast for Onjuku over the next 16 days: The first swell (rated 1 star or higher) is forecast to arrive on Sunday (Jul 26) at 3AM. The primary swell is predicted to be 0.9m and 8s period with a secondary swell of 0.5m and 10s. The wind is predicted to be offshore as the swell arrives.

The most powerful waves expected at Onjuku in the next 16 days are 1.2m 8s and forecast to arrive on Sunday (Jul 26) at 6AM. Winds are predicted to be cross-offshore at the time the swell arrives. The largest open ocean swell (not directed at the beach) is 1.0m 6s period and expected on Monday (Jul 27) at 3PM.

Wave TypeTime (JST) & Date Wave Height & Period
Next good surf (1 star+) 3AM (Sun 26th Jul)3ft (0.9m) 8s
Best Surf 3AM (Sun 26th Jul)3ft (0.9m) 8s
Most Powerful 6AM (Sun 26th Jul)4ft (1.2m) 8s

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


The Lowdown

Alright, Rusty here again. Let's have a look at what's on offer for Onjuku over the next couple of weeks. It's a bit of a mixed bag, with a serious reality check coming our way in the second week.

First thing's first, there's no surf worth paddling out for right now. We've got a gap from now until Sunday morning before anything decent shows up.

Sunday 26th July
Alright, we're on! Sunday morning is looking like the pick of the early days. We've got clean 3ft waves from the ENE with a short period, light cross-offshore breeze from the NE, and the combined energy is moderate at 224. The water temp is about average for this time of year. It's not going to be massive, but for a summer session, Onjuku will be offering some fun, clean lines. It's an exposed spot, so it'll pick up anything going. Worth a look.

Monday 27th July
Things drop right off. We're into poor surf conditions with small, messy waves. Not worth the wetsuit.

Tuesday 28th July
Tuesday morning sees a return to 3ft from the ENE, again clean under a light NE breeze. The period is still short, and energy is moderate (206). It's another clean window, similar to Sunday, but probably not quite as good.

Wednesday 29th July
Wednesday morning is the standout of the first week. The swell bumps up to 4ft from the NE, and we’ve got a gentle offshore breeze from the NNE. The wind is the key here – that offshore flow will keep the surface glassy and clean, giving us some really tidy peaks. Combined energy is moderate at 257. This is the morning to be out there.

Thursday 30th July
Thursday morning offers a little something with 2ft waves and glassy conditions from a southerly breeze. It'll be surfable but very ordinary. A good session for a log or a longboard.

Friday 31st July to Saturday 1st August
A slump. Small, weak, and onshore. Not worth the drive.

Sunday 2nd August
A slight pulse of energy arrives Sunday afternoon with a long-period 2ft SE swell, but the conditions are described as marginal. The energy is moderate at 260, but this is a tease of what's to come.

Monday 3rd August onwards – The Big Stuff
Now, here's where it gets serious and a bit sad for us. From Monday 3rd August, a massive, powerful SE groundswell starts to build. Swell heights climb from 5ft on Monday morning up to a staggering 23ft by Saturday 8th August. The period is very long at 16 to 17 seconds and the combined energy goes through the roof, reaching astronomical values of 36,074. This is a proper, XXL swell event.

But here's the harsh truth for Onjuku: this break is simply too big for this spot. From Wednesday 5th August onwards, the forecast notes that the swell is predicted to be too big for this break. For a surfer, that means it's going to be a washing machine. Massive, unruly, and likely unsurfable here. The conditions are clean with offshore winds, but the size is just too much. This is strictly for the experts with a death wish, or more likely, for the big-wave tow crews. For the rest of us, it's a no-go at Onjuku.

If you like looking at big, angry ocean, you'll be stoked. If you want to paddle out, you'll be looking at the beach breaks from the car park.

Monday 10th August
After that monster week, things finally drop back. We're down to 4ft from the ESE with a moderate period of 13 seconds and some cross-onshore breeze. Conditions are still marginal, but at least it's back to a more manageable size.

So, the real standout here is Wednesday 29th July morning for the clean, offshore conditions and solid, surfable waves. For a proper test, keep an eye on the early days. After that, it's a big, beautiful, and totally un-surfable ocean for Onjuku.

Rusty.

Short Range Forecast

Heavy rain (total 30mm), heaviest during Sat night. Warm (max 27°C on Sun morning, min 23°C on Sun night). Wind will be generally light.

Days 5-7 Weather Summary

Moderate rain (total 13mm), heaviest on Tue night. Warm (max 29°C on Fri morning, min 23°C on Tue night). Wind will be generally light.

Sunday
26
Monday
27
Tuesday
28
Wednesday
29
Thursday
30
Friday
31
Night
AM
PM
Night
AM
PM
Night
AM
PM
Night
AM
PM
Night
AM
PM
Night
AM
PM
Night
Rating
(10 max)
1
2
1
0
0
0
1
2
0
1
2
1
1
1
0
0
0
0
1
Swell
Height Map
Height Map
Height Map
Height Map
Height Map
Height Map
Height Map
Height Map
Wave
Height (m)
Direction
Period (s)
0.5
SE
10
1
ENE
7
0.9
ENE
7
0.4
SE
14
0.5
SE
10
0.6
SE
10
0.6
SE
10
1
ENE
8
1
E
8
0.9
ENE
8
1.1
NE
7
1
ENE
6
0.8
ENE
7
0.7
ENE
8
0.6
ENE
8
0.4
SE
9
0.7
SSW
6
0.7
SSW
7
0.4
SE
9
Wave Graph
Metric surfscale
Energy kJ
50
114
86
72
51
63
63
133
133
109
118
80
61
65
47
31
40
47
31
Wind (km/h)
10
N
10
NE
10
SSE
10
S
20
NE
20
ENE
15
NNE
10
NE
5
ESE
15
NNE
15
NNE
15
ENE
10
NE
5
S
20
SSW
20
SW
10
SSW
10
SSW
5
NW
Wind State
off
cross-off
cross-on
on
cross-off
cross-off
cross-off
cross-off
cross-on
off
off
cross-off
cross-off
glassy
cross-on
cross-on
cross-on
on
glassy
High Tide
00:24AM1.25m
4:42PM1.19m
1:35AM1.28m
5:00PM1.23m
2:32AM1.33m
5:21PM1.27m
3:19AM1.38m
5:42PM1.30m
4:01AM1.42m
6:03PM1.32m
4:41AM1.43m
6:23PM1.34m
Low Tide
8:43AM0.30m
8:40PM1.07m
9:26AM0.23m
9:28PM1.02m
10:04AM0.17m
10:04PM0.97m
10:37AM0.13m
10:38PM0.90m
11:08AM0.12m
11:11PM0.83m
11:38AM0.14m
11:45PM0.75m
rain showers
thunderstorm
part cloud
thunderstorm
thunderstorm
clear
part cloud
part cloud
thunderstorm
rain showers
part cloud
part cloud
part cloud
part cloud
part cloud
clear
part cloud
part cloud
part cloud
<span class="translation_missing" title="translation missing: en.weather_tables.sunrise">Sunrise</span>
4:41
4:43
4:43
4:43
4:45
4:46
<span class="translation_missing" title="translation missing: en.weather_tables.sunset">Sunset</span>
6:47
6:46
6:45
6:45
6:45
6:44
6:43
 mm
13
1
11
1
4
13
Temp °C
24
27
27
26
25
25
23
26
26
23
26
25
24
27
27
27
29
29
27
Feels °C
26
31
30
28
25
26
24
29
30
24
27
26
27
29
28
32
33
33
31
  • Map Icons:
  • Break
  • Live Wave Height (m)
  • Live Wind Speed (km/h)
  • Surf Rating (10 Max)
  • Ocean Swells (m)
  • Wind Speed (km/h)
Map placeholder
How to use the Wavefinder 
submit an eyeball surf report

Quick surf report for Onjuku:

join our community of surf reporters

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 Onjuku 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.


Information about the Onjuku Surf forecast

The above surf forecast table for Onjuku provides essential information for determining whether the surfing conditions will be good over the next 16 days. A general guide to surfing at Onjuku can be found by selecting the local surf guide option on the grey menu. Our Onjuku 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 (Onjuku) 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 Onjuku 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.

Onjuku is 3 km (2 miles) from Ohara. If you plan a holiday in Chiba, look for hotels and other accommodation in Ohara. Ohara has rooms for a wide range of budgets as well as car hire and transport links.

Nearest locationNearest