Surf Forecasts:
Trespassers surf forecast from 18 Aug 2026:
- Best quality surf: Saturday 22 Aug, 9PM (local time) - 4.5ft (1.4m), 15s period, SW swell with cross-offshore winds.
- Most powerful swell: Tuesday 25 Aug, 6AM (local time) - 7ft (2.1m), 16s period, SW swell with 2,269 kJ wave energy.
- Next surfable swell (1★+): Saturday 22 Aug, 9PM (local time) - 4.5ft (1.4m), 15s period with SW swell.
Best Forecast Surf Conditions for Trespassers this week:
The surf forecast for Trespassers over the next 16 days: The first swell (rated 1 star or higher) is forecast to arrive on Saturday (Aug 22) at 9PM. The primary swell is predicted to be 1.4m and 15s period with a secondary swell of 0.8m and 19s. The wind is predicted to be cross-offshore as the swell arrives.
The most powerful waves expected at Trespassers in the next 16 days are 2.1m 16s and forecast to arrive on Tuesday (Aug 25) at 6AM. Winds are predicted to be cross-shore at the time the swell arrives. The largest open ocean swell (not directed at the beach) is 0.3m 3s period and expected on Sunday (Aug 23) at 3PM.
| Wave Type | Time (ACST) & Date | Wave Height & Period |
|---|---|---|
| Next good surf (1 star+) | 9PM (Sat 22nd Aug) | 4.5ft (1.4m) 15s |
| Best Surf | 9PM (Sat 22nd Aug) | 4.5ft (1.4m) 15s |
| Most Powerful | 6AM (Tue 25th Aug) | 7ft (2.1m) 16s |
Table - best surf conditions forecast for Trespassers over the next 16 days.
The Lowdown
Alright, let's get into it. This is Rusty.
The first week of this forecast has a lot of lumpy, onshore-affected surf, and we’ll be waiting until the morning of Friday the 23rd before we see anything that’s even close to decent. Even then, it’s a bit of a tease. The real standout starts to come together around the 26th, and then again late in the run on the 29th.
The only spot we’re looking at is Trespassers. It’s an advanced reef break, and it’s fairly consistent. The water temp is sitting at 59°F, which is about normal for this time of year, so no surprises there.
For the first few days, it’s grim. Wednesday and Thursday mornings are a write-off with strong cross-on winds and poor surf. The swell is there, but it’s not clean. The combined energy on Wednesday afternoon hits 1589 (moderate to strong), but a 30 km/h onshore wind just ruins it. Friday the 21st is a bit of a tease – we’ve got a 5ft swell from the SW, but the wind is still cross-on and the conditions are “marginal.” It’s a no-go.
Saturday the 22nd is similar. The swell is pumping, with a 6ft SW swell and a 16-second period, but the energy is high (1466) and the wind is still cross-on. The morning is the best of a bad bunch, with a light breeze and small wind ripples, but it’s still not what you’d paddle out for.
Now, Sunday the 23rd is the first real glimmer. The morning brings a clean 5ft SW groundswell (a 17-second period) with a light cross-off breeze from the NNE. The combined energy is 1193 (moderate). This is the first time we see “clean” in the data, and with a score of 3, it’s the best on offer so far. It’s not huge, but it’s the closest we get to quality in the first week. The afternoon goes cross-shore, so the window is narrow.
Then we hit a flat spot. Monday the 24th is a dud with light rain and onshore wind, and the swell drops to 3ft.
Tuesday the 25th brings a bigger, messier swell. 7ft from the SW at 13 seconds, but with a cross-shore wind and a cross-chop, it’s not a paddle session. The energy is strong (1638), but the conditions are marginal. For a reef break, that period is a bit short, and the wind is going to make it a battle.
Alright, here’s the real standout. Wednesday the 26th. The morning is glassy. A 4ft SW swell, but the wind is dead calm – 5 km/h from the W. The combined energy is 431 (moderate), and the conditions are described as “glassy.” This is a window of pure, clean surf. It’s not a big day, but it’s a perfect little morning session for the advanced crew. After that, the wind turns onshore again.
The next few days are a mix of clean but small surf. Friday the 28th has a stronger 6ft SW swell (16-second period, 1694 energy), but it’s cross-shore and marginal. Saturday the 29th is where it gets interesting again. The morning has a 4ft SSW swell with a light cross-off breeze from the ESE. The afternoon is where it’s at: a 3ft SSW swell with a clean offshore wind from the ESE. The energy is 411 (moderate), but it’s clean. This is a good, fun-size afternoon session.
Sunday the 30th is a proper drop-off. The swell is tiny at 1ft, but with a 19-second period and clean offshore wind, it’s a longboarder’s dream. The energy is low (392), but it’s a beautiful, glassy day.
The rest of the forecast into September is small, clean, and marginal. The swell stays under 4ft, and the winds are generally offshore or cross-off. It’s not a week for power, but for a clean, cruisy board, there are some nice windows.
So, the best on offer? Wednesday the 26th morning for that glassy, clean 4ft swell. And Saturday the 29th afternoon for the clean offshore wind and a fun-sized 3ft. The deep water swell on the 23rd is the best of the first week, but it’s a short window.
Rusty.
Short Range ForecastSome drizzle, heaviest during Wed morning. Very mild (max 14°C on Wed morning, min 13°C on Wed morning). Winds decreasing (fresh winds from the WNW on Wed morning, light winds from the WSW by Fri morning). | Days 4-6 Weather SummaryLight rain (total 5mm), mostly falling on Sun night. Very mild (max 15°C on Sun night, min 12°C on Sat night). Wind will be generally light. | ||||||||||||||||||||
Wednesday 19 | Thursday 20 | Friday 21 | Saturday 22 | Sunday 23 | Monday 24 | Tuesday 25 | |||||||||||||||
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) | W 8 | WSW 15 | SW 13 | SW 16 | SW 16 | SW 16 | SW 14 | SW 17 | SW 16 | SW 16 | SW 15 | SW 15 | SW 17 | SSW 16 | SW 15 | SSW 14 | SW 14 | SW 13 | SW 13 | SW 14 | SW 12 |
Wave Graph | |||||||||||||||||||||
277 | 1409 | 780 | 954 | 489 | 1149 | 899 | 1663 | 1532 | 1412 | 1074 | 869 | 1193 | 832 | 496 | 261 | 696 | 969 | 1387 | 1438 | 531 | |
Wind (km/h) | |||||||||||||||||||||
Wind State on-shore cross-onshore cross-shore cross-offshore off-shore glassy | cross-on | on | on | cross-on | on | cross-on | cross-on | on | cross-on | cross-on | on | cross-off | cross-off | cross | cross-on | on | cross-on | cross | cross | cross-on | cross |
High Tide | 3:32PM0.02m | 2:53PM0.02m | 2:19PM0.02m | 2:13PM0.02m | 2:21PM0.02m | 2:29PM0.02m | 2:56AM0.01m | 2:43PM0.02m | 3:00AM0.01m | ||||||||||||
Low Tide | 11:06AM0.01m | 11:48PM-0.00m | 00:04AM0.00m | 00:16AM0.00m | 00:18AM0.00m | 11:45PM0.00m | 11:01PM0.00m | 6:33AM0.00m | 10:36PM0.00m | ||||||||||||
6:58 | — | — | 6:58 | — | — | 6:56 | — | — | 6:54 | — | — | 6:54 | — | — | 6:52 | — | — | 6:52 | — | — | |
— | 5:52 | — | — | 5:52 | — | — | 5:53 | — | — | 5:54 | — | — | 5:55 | — | — | 5:55 | — | — | 5:57 | — | |
mm | 1 | — | — | — | — | — | — | — | — | — | — | — | — | — | 1 | 2 | — | 2 | 1 | — | — |
Temp °C | 14 | 14 | 14 | 14 | 14 | 14 | 13 | 14 | 14 | 14 | 13 | 13 | 14 | 14 | 15 | 15 | 14 | 13 | 13 | 13 | 12 |
Feels °C | 8 | 7 | 10 | 9 | 10 | 11 | 9 | 11 | 11 | 12 | 10 | 12 | 11 | 11 | 12 | 11 | 9 | 9 | 8 | 7 | 8 |
Swell 1 Height (m) Direction Period (s) | SW 15 | SSW 14 | SW 13 | SW 16 | SW 16 | SW 16 | SW 14 | SW 17 | SW 16 | SW 16 | SW 15 | SW 15 | SW 17 | SSW 16 | SW 15 | SSW 14 | SSW 14 | SW 13 | SW 16 | SW 14 | SW 12 |
236 | 140 | 780 | 954 | 489 | 1149 | 899 | 1663 | 1532 | 1412 | 1074 | 869 | 1193 | 832 | 496 | 261 | 78 | 138 | 251 | 513 | 531 | |
Swell 2 Height (m) Direction Period (s) | SSW 15 | SSW 20 | SW 18 | SSW 16 | — | SW 20 | SW 18 | — | — | SSW 23 | SSW 21 | SW 19 | — | — | S 22 | SSW 20 | SSW 19 | SW 18 | — | — | SW 14 |
152 | 40 | 263 | 162 | — | 136 | 455 | — | — | 54 | 302 | 376 | — | — | 9 | 38 | 37 | 150 | — | — | 132 | |
Swell 3 Height (m) Direction Period (s) | — | — | SW 18 | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
— | — | 260 | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | |
Wind waves Height (m) Direction Period (s) | W 8 | WSW 15 | W 10 | NW 4 | WSW 10 | WSW 9 | — | — | — | — | — | — | — | NNE 3 | N 2 | WNW 3 | SW 14 | SW 13 | SW 13 | SW 14 | SSE 3 |
277 | 1409 | 479 | 9 | 241 | 135 | — | — | — | — | — | — | — | 1 | 1 | 6 | 696 | 969 | 1387 | 1438 | 2 | |
Nearest Offshore or Glassy | |||||||||||||||||||||
Distance (km) | 480 | 546 | 17 | 14 | 546 | 13 | 14 | 138 | 13 | 13 | 14 | 0 | 0 | 14 | 14 | 17 | 161 | 13 | 13 | 59 | 11 |
Best forecast wave conditions in Yorke Peninsula | |||||||||||||||||||||
Best forecast wave conditions in Australia | |||||||||||||||||||||
Header Global | |||||||||||||||||||||
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Information about the Trespassers Surf forecast
The above surf forecast table for Trespassers provides essential information for determining whether the surfing conditions will be good over the next 16 days. A general guide to surfing at Trespassers can be found by selecting the local surf guide option on the grey menu. Our Trespassers 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 (Trespassers) 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 Trespassers 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.
Are you planning a holiday in Yorke Peninsula? If you are looking for accommodation near Trespassers, camping, hotels and holiday cottages in Yorke Peninsula, consider staying in Kingscote which is 86 km (53 miles) away.











