
Surf Forecasts:
Onjuku surf forecast from 15 Sep 2026:
- Best quality surf: Tuesday 22 Sep, 3PM (local time) - 15ft (4.5m), 9s period, S swell with cross-onshore winds.
- Most powerful swell: Tuesday 22 Sep, 9AM (local time) - 10ft (3.0m), 14s period, S swell with 3,247 kJ wave energy.
- Next surfable swell (1★+): Tuesday 15 Sep, 9PM (local time) - 4.5ft (1.3m), 7s period with SE 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 Tuesday (Sep 15) at 9PM. The primary swell is predicted to be 0.7m and 13s period with a secondary swell of 1.3m and 7s. Another secondary swell of 1.3m and 6s is also forecast. The wind is predicted to be offshore as the swell arrives.
The most powerful waves expected at Onjuku in the next 16 days are 3.0m 14s and forecast to arrive on Tuesday (Sep 22) at 9AM. Winds are predicted to be cross-offshore at the time the swell arrives. The largest open ocean swell (not directed at the beach) is 1.4m 8s period and expected on Saturday (Sep 19) at 9PM.
| Wave Type | Time (JST) & Date | Wave Height & Period |
|---|---|---|
| Next good surf (1 star+) | 9PM (Tue 15th Sep) | 4.5ft (1.3m) 7s |
| Best Surf | 3PM (Tue 22nd Sep) | 15ft (4.5m) 9s |
| Most Powerful | 9AM (Tue 22nd Sep) | 10ft (3.0m) 14s |
Table - best surf conditions forecast for Onjuku over the next 16 days.
Short Range ForecastHeavy rain (total 52mm), heaviest during Wed morning. Warm (max 26°C on Tue afternoon, min 19°C on Wed night). Winds increasing (light winds from the SW on Tue afternoon, strong winds from the NNE by Thu morning). | Days 4-6 Weather SummaryHeavy rain (total 42mm), heaviest during Sun morning. Warm (max 22°C on Sat night, min 20°C on Fri morning). Mainly strong winds. | ||||||||||||||||||||
Tuesday 15 | Wednesday 16 | Thursday 17 | Friday 18 | Saturday 19 | Sunday 20 | Monday 21 | |||||||||||||||
AM | PM | Night | AM | PM | Night | AM | PM | Night | AM | PM | Night | AM | PM | Night | AM | PM | Night | AM | PM | Night | |
Swell Height Map | |||||||||||||||||||||
Wave Height (m) Direction Period (s) | E 14 | E 14 | E 13 | E 13 | E 12 | ENE 7 | NE 7 | ENE 8 | ENE 8 | ENE 9 | ENE 9 | SE 14 | SE 13 | SE 12 | SE 11 | SE 11 | SE 12 | S 12 | S 13 | S 13 | S 13 |
Wave Graph | |||||||||||||||||||||
195 | 261 | 167 | 215 | 148 | 175 | 589 | 732 | 635 | 848 | 905 | 2509 | 2076 | 1866 | 1667 | 1298 | 1470 | 870 | 1163 | 1346 | 1632 | |
Wind (km/h) | |||||||||||||||||||||
Wind State on-shore cross-onshore cross-shore cross-offshore off-shore glassy | on | cross-on | off | cross-off | cross-off | off | cross-off | cross-off | off | off | cross-off | off | cross-off | off | cross-off | off | off | cross-off | cross-off | cross-off | cross-off |
High Tide | 6:03PM1.43m | 7:26AM1.19m | 6:22PM1.41m | 8:14AM1.09m | 6:42PM1.37m | 9:27AM0.99m | 7:03PM1.31m | 7:24PM1.24m | 7:46PM1.15m | 3:28PM1.16m | 11:46PM1.11m | ||||||||||
Low Tide | 12:11PM0.69m | 00:53AM0.27m | 12:28PM0.79m | 1:31AM0.32m | 12:40PM0.87m | 2:15AM0.40m | 12:34PM0.94m | 3:18AM0.48m | 5:00AM0.52m | 6:47AM0.49m | 8:11PM1.06m | ||||||||||
5:20 | — | — | 5:20 | — | — | 5:22 | — | — | 5:22 | — | — | 5:22 | — | — | 5:24 | — | — | 5:24 | — | — | |
— | 5:46 | — | — | 5:45 | — | — | 5:44 | — | — | 5:42 | — | — | 5:40 | — | — | 5:38 | — | — | 5:37 | — | |
mm | 6 | 3 | 7 | 9 | 9 | 17 | 1 | — | — | — | — | — | — | 9 | 18 | 15 | — | — | — | 1 | 2 |
Temp °C | 25 | 26 | 24 | 22 | 22 | 23 | 20 | 20 | 20 | 21 | 20 | 20 | 21 | 21 | 22 | 21 | 22 | 22 | 24 | 24 | 24 |
Feels °C | 27 | 29 | 27 | 22 | 21 | 26 | 14 | 15 | 15 | 15 | 14 | 15 | 17 | 17 | 21 | 19 | 21 | 22 | 24 | 24 | 25 |
Swell 1 Height (m) Direction Period (s) | SE 8 | SE 7 | SE 6 | SSE 7 | SE 8 | SE 8 | E 12 | SSE 9 | SE 9 | SSE 18 | SE 16 | SE 14 | SE 13 | SE 12 | SE 11 | SE 11 | SE 12 | ESE 9 | S 13 | S 13 | S 13 |
181 | 156 | 123 | 83 | 69 | 53 | 44 | 8 | 3 | 32 | 653 | 2509 | 2076 | 1866 | 1667 | 1298 | 1470 | 554 | 1163 | 1346 | 1632 | |
Swell 2 Height (m) Direction Period (s) | E 14 | E 14 | E 13 | E 13 | E 12 | E 12 | E 15 | ENE 11 | SSE 9 | SE 12 | SSE 11 | — | E 10 | E 10 | NE 9 | E 14 | E 13 | S 12 | E 9 | SE 9 | E 9 |
195 | 261 | 167 | 215 | 148 | 71 | 4 | 24 | 8 | 6 | 12 | — | 54 | 125 | 221 | 14 | 30 | 870 | 355 | 112 | 198 | |
Swell 3 Height (m) Direction Period (s) | ENE 7 | NE 10 | SW 6 | SSW 6 | — | E 16 | E 15 | SSE 9 | SSE 9 | SE 9 | SE 11 | — | — | — | E 10 | E 14 | E 13 | E 12 | E 10 | SE 9 | SE 8 |
10 | 4 | 43 | 13 | — | 5 | 17 | 8 | 8 | 3 | 30 | — | — | — | 100 | 14 | 50 | 66 | 108 | 91 | 49 | |
Wind waves Height (m) Direction Period (s) | — | — | — | NE 5 | NE 6 | ENE 7 | NE 7 | ENE 8 | ENE 8 | ENE 9 | ENE 9 | ENE 8 | NE 8 | NE 7 | — | NE 4 | NE 5 | NNE 5 | ENE 11 | ENE 10 | — |
— | — | — | 35 | 103 | 175 | 589 | 732 | 635 | 848 | 905 | 538 | 485 | 248 | — | 19 | 65 | 46 | 575 | 348 | — | |
Nearest Offshore or Glassy | |||||||||||||||||||||
Distance (km) | 9 | 9 | 0 | 56 | 56 | 0 | 206 | 617 | 536 | 553 | 206 | 536 | 295 | 617 | 554 | 295 | 206 | 51 | 51 | 631 | 22 |
Best forecast wave conditions in Chiba | |||||||||||||||||||||
Best forecast wave conditions in Japan | |||||||||||||||||||||
Header Global | |||||||||||||||||||||
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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.










