
Surf Forecasts:
Siriu surf forecast from 10 Aug 2026:
- Best quality surf: Monday 10 Aug, 9AM (local time) - 7ft (2.2m), 12s period, S swell with cross-offshore winds.
- Most powerful swell: Monday 10 Aug, 6PM (local time) - 8ft (2.4m), 12s period, S swell with 1,656 kJ wave energy.
- Next surfable swell (1★+): Monday 10 Aug, 6AM (local time) - 6ft (1.8m), 12s period with SSE swell.
Best Forecast Surf Conditions for Siriu this week:
The surf forecast for Siriu over the next 16 days: The first swell (rated 1 star or higher) is forecast to arrive on Monday (Aug 10) at 6AM. The primary swell is predicted to be 1.8m and 12s period with a secondary swell of 0.4m and 8s. The wind is predicted to be cross-offshore as the swell arrives.
The most powerful waves expected at Siriu in the next 16 days are 2.4m 12s and forecast to arrive on Monday (Aug 10) at 6PM. Winds are predicted to be cross-offshore at the time the swell arrives. The largest open ocean swell (not directed at the beach) is 0.5m 4s period and expected on Saturday (Aug 15) at 3AM.
| Wave Type | Time (-03) & Date | Wave Height & Period |
|---|---|---|
| Next good surf (1 star+) | 6AM (Mon 10th Aug) | 6ft (1.8m) 12s |
| Best Surf | 9AM (Mon 10th Aug) | 7ft (2.2m) 12s |
| Most Powerful | 6PM (Mon 10th Aug) | 8ft (2.4m) 12s |
Table - best surf conditions forecast for Siriu over the next 16 days.
The Lowdown
Alright, Rusty here, checking in on the waves for the next couple of weeks. It’s a bit of a mixed bag for us, so let’s get into it.
First up, the standout window hits us early. Monday the 10th of August is looking promising, with some solid S swell (7 ft) and a 12-second period pushing a heap of energy through (2246). The wind is cross-off in the morning, keeping things clean. This is strong wave energy, so it’s going to be a proper session for experienced surfers.
The absolute gem in this run looks to be Tuesday morning the 11th of August at Siriu. Swell drops a touch to 7 ft from the SSE, but the wind goes glassy. This is the kind of morning you wait for – smooth, clean lines and manageable size. The period stays at 12 seconds which gives the waves some shape and push, and the energy is still top-notch (1177). A real highlight.
After that, things get messy. Swell holds around 5 ft to 6 ft through the rest of the week, but the wind turns cross or onshore, and the energy drops steadily. Wednesday and Thursday are surfable but bumpy, with the wave quality taking a big hit.
We hit a rough patch from the 16th of August through the 20th. Swell gets small (2 ft to 4 ft), wind is mostly cross or cross-on, and the conditions look ordinary. It’s a solid five-day stretch of poor to marginal surf, so don’t expect much.
There’s a late flicker of hope on Friday the 21st of August. The swell picks up a little, period stretches to 13 seconds, and the morning is glassy with WSW winds. The size is small at 3 ft, but the quality should be there for a clean, small-wave session. It’s the best of a quiet end to the run.
From the 22nd, the swell bumps back up (around 6 ft), but the wind turns cross again, and the quality is only marginal. The final week fades out with small, bumpy, and mostly poor conditions. A couple of bright days early, then a long wait for much else.
Stay patient, pick your mornings.
Rusty.
Short Range ForecastLight rain (total 6mm), mostly falling on Sun night. Very mild (max 15°C on Mon afternoon, min 11°C on Sun night). Wind will be generally light. | Days 5-7 Weather SummaryModerate rain (total 17mm), heaviest on Sat morning. Warm (max 21°C on Fri morning, min 15°C on Wed night). Wind will be generally light. | ||||||||||||||||||
Monday 10 | Tuesday 11 | Wednesday 12 | Thursday 13 | Friday 14 | Saturday 15 | ||||||||||||||
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) | SSE 12 | S 12 | S 12 | SSE 12 | SSE 12 | SSE 12 | SSE 12 | SSE 12 | SSE 12 | SSE 12 | SSE 14 | SSE 14 | SSE 13 | SSE 13 | SSE 13 | SSE 12 | SSE 12 | SSE 11 | SSE 10 |
Wave Graph | |||||||||||||||||||
1001 | 1369 | 1581 | 1338 | 1164 | 985 | 1016 | 918 | 824 | 706 | 1374 | 1179 | 786 | 721 | 905 | 531 | 422 | 419 | 195 | |
Wind (km/h) | |||||||||||||||||||
Wind State on-shore cross-onshore cross-shore cross-offshore off-shore glassy | cross-off | cross-off | cross | cross-off | glassy | glassy | cross | cross | cross-on | cross | cross | cross | cross-off | cross | cross | cross-off | off | cross | glassy |
High Tide | 00:39AM0.49m | 2:19PM0.83m | 00:41AM0.55m | 2:47PM0.81m | 00:59AM0.63m | 3:02PM0.76m | 1:25AM0.70m | 3:05PM0.70m | 1:55AM0.76m | 3:10PM0.66m | 2:28AM0.79m | 3:22PM0.63m | |||||||
Low Tide | 6:52AM0.01m | 8:05PM0.31m | 7:36AM-0.05m | 8:33PM0.34m | 8:17AM-0.08m | 8:57PM0.36m | 8:54AM-0.06m | 9:18PM0.37m | 9:28AM-0.01m | 9:33PM0.36m | 9:58AM0.07m | 9:39PM0.33m | |||||||
— | 6:50 | — | — | 6:48 | — | — | 6:48 | — | — | 6:47 | — | — | 6:46 | — | — | 6:46 | — | — | |
— | — | 5:49 | — | — | 5:50 | — | — | 5:50 | — | — | 5:51 | — | — | 5:51 | — | — | 5:52 | — | |
mm | 3 | — | — | — | — | — | — | 2 | 1 | — | — | — | 3 | — | 1 | 7 | 4 | 2 | 3 |
Temp °C | 12 | 14 | 15 | 12 | 13 | 13 | 13 | 13 | 15 | 15 | 20 | 19 | 18 | 21 | 21 | 19 | 19 | 19 | 18 |
Feels °C | 10 | 9 | 10 | 9 | 12 | 12 | 12 | 11 | 13 | 12 | 21 | 19 | 19 | 22 | 22 | 20 | 21 | 20 | 19 |
Swell 1 Height (m) Direction Period (s) | SSE 12 | S 12 | S 13 | SSE 12 | SSE 12 | SSE 12 | SSE 12 | SSE 12 | SSE 12 | SSE 12 | SSE 14 | SSE 14 | SSE 13 | SSE 13 | SSE 13 | SSE 12 | SSE 12 | SSE 11 | SSE 10 |
1001 | 855 | 1037 | 1338 | 1164 | 985 | 1016 | 918 | 824 | 706 | 1374 | 1179 | 786 | 721 | 905 | 531 | 422 | 419 | 195 | |
Swell 2 Height (m) Direction Period (s) | ENE 8 | ENE 8 | ENE 9 | ENE 8 | ENE 8 | ENE 8 | ENE 8 | ENE 7 | ENE 7 | ENE 7 | NE 5 | NE 6 | NE 6 | NE 6 | ENE 6 | NE 4 | ENE 6 | ENE 7 | ENE 7 |
32 | 22 | 44 | 27 | 13 | 12 | 11 | 5 | 5 | 5 | 21 | 25 | 22 | 18 | 15 | 16 | 45 | 54 | 54 | |
Swell 3 Height (m) Direction Period (s) | E 13 | — | — | — | — | — | — | — | — | — | — | — | — | NE 6 | NE 6 | SE 8 | SE 8 | E 16 | SE 8 |
3 | — | — | — | — | — | — | — | — | — | — | — | — | 29 | 18 | 42 | 28 | 5 | 45 | |
Wind waves Height (m) Direction Period (s) | — | S 12 | S 12 | — | — | — | — | NE 7 | NE 7 | NNE 4 | NNE 5 | — | — | — | — | NNE 4 | — | — | — |
— | 1369 | 1581 | — | — | — | — | 13 | 12 | 15 | 47 | — | — | — | — | 32 | — | — | — | |
Nearest Offshore or Glassy | |||||||||||||||||||
Distance (km) | 0 | 0 | 38 | 0 | 0 | 0 | 9 | 9 | 9 | 27 | 6 | 13 | 0 | 6 | 9 | 0 | 0 | 13 | 0 |
Best forecast wave conditions in Santa Catarina - Sul | |||||||||||||||||||
Best forecast wave conditions in Brazil | |||||||||||||||||||
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Information about the Siriu Surf forecast
The above surf forecast table for Siriu provides essential information for determining whether the surfing conditions will be good over the next 16 days. A general guide to surfing at Siriu can be found by selecting the local surf guide option on the grey menu. Our Siriu 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 (Siriu) 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 Siriu 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.
Siriu is 27 km (17 miles) from Imbituba. If you plan a holiday in Santa Catarina - Sul, look for hotels and other accommodation in Imbituba. Imbituba has rooms for a wide range of budgets as well as car hire and transport links.











