Surf Forecasts:
Siriu surf forecast from 29 Aug 2026:
- Best quality surf: Wednesday 2 Sep, 9AM (local time) - 10ft (3.0m), 9s period, S swell with cross-offshore winds.
- Most powerful swell: Wednesday 2 Sep, 9AM (local time) - 10ft (3.0m), 9s period, S swell with 1,412 kJ wave energy.
- Next surfable swell (1★+): Saturday 29 Aug, 9PM (local time) - 4ft (1.2m), 8s period with ENE 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 Saturday (Aug 29) at 9PM. The primary swell is predicted to be 1.2m and 8s period with a secondary swell of 0.2m and 10s. Another secondary swell of 0.4m and 4s is also forecast. 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 3.0m 9s and forecast to arrive on Wednesday (Sep 02) 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 2.5m 9s period and expected on Wednesday (Sep 02) at 12AM.
| Wave Type | Time (-03) & Date | Wave Height & Period |
|---|---|---|
| Next good surf (1 star+) | 9PM (Sat 29th Aug) | 4ft (1.2m) 8s |
| Best Surf | 9AM (Wed 2nd Sep) | 10ft (3.0m) 9s |
| Most Powerful | 9AM (Wed 2nd Sep) | 10ft (3.0m) 9s |
Table - best surf conditions forecast for Siriu over the next 16 days.
The Lowdown
Alright, Rusty here, checkin’ the forecast for Siriu.
Looking at the next 16 days, we’ve got some ups and downs. Water’s at 19°, which is exactly where it should be for this time of year, nothing weird going on.
We start off this Saturday, August 29th, a bit weak. There’s an ENE swell running about 5ft with a real short period, just 8 seconds. The wind is a cross-off from the SSW, so it’s clean-ish, but the wave energy is real low at 281. Just a so-so session.
Sunday the 30th drops even more, to about 3ft from the east. The morning is meh, but the afternoon turns glassy, flat calm. It’ll be pretty to look at, but there’s no push in the water.
Monday the 31st is where we get a little life. The morning is glassy with a light breeze, and the swell comes up to 4ft. Energy jumps to 350, and it’s set to be a good, clean, small-wave session. This is a nice window for the big boards or beginners.
But Monday afternoon goes wild. Swell hits 8ft from the ESE, energy rockets to 1657 (strong), but the wind comes onshore from the NE, making it a choppy mess. At 8ft, that’s big, tough stuff – only for the brave, and even then, it won’t be pretty.
Tuesday, September 1st, morning is clean again at 5ft, but the afternoon gets wrecked by a strong, 22 mph cross-off wind.
Then comes a big one: Wednesday, September 2nd, morning. The swell is predicted at 10ft from the south with a 9-second period. The energy is massive at 2410. The wind is light and offshore, so it’ll look beautiful. But the data also warns it might be too big for this spot. It’s a serious, expert-only proposition, and the forecast says the setup isn’t right for it. Might be more of a show than a go.
After that we get a few days of small stuff – 3ft to 5ft – with messy wind.
The real gem in the second week is Tuesday, September 8th, morning. The forecast shows 6ft from the SSE with a solid 11-second period. The energy is 805 (moderate-strong), and it’s supposed to be "very good surf conditions" with glassy wind. That 11-second period is going to give these waves some real grunt and shape. This is the session to wait for.
From the 9th to the 12th it’s a mix of small swell and onshore chop. Nothing to get excited about.
Finally, on Sunday, September 13th, morning, we get another glassy window. Swell at 5ft from the east, 8-second period, energy of 513. The data says "very good surf conditions." It’ll be clean and fun, but not as powerful as the 8th.
Best calls: For a clean, small wave, hit the Monday, August 31st, morning. For the best quality of the whole forecast, you want the Tuesday, September 8th, morning – that’s the one with the grunt and the glass. The Sunday, September 13th, morning is a solid backup for a clean, smaller wave.
Keep your head on a swivel.
Rusty
Short Range ForecastHeavy rain (total 115mm), heaviest during Mon night. Warm (max 20°C on Mon night, min 17°C on Sat night). Wind will be generally light. | Days 4-6 Weather SummarySome drizzle, heaviest during Tue morning. Warm (max 20°C on Tue morning, min 12°C on Tue night). Winds decreasing (fresh winds from the SSW on Tue afternoon, light winds from the E by Wed afternoon). | ||||||||||||||||||||
Saturday 29 | Sunday 30 | Monday 31 | Tuesday 1 | Wednesday 2 | Thursday 3 | Friday 4 | |||||||||||||||
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) | ENE 8 | ENE 8 | ENE 8 | E 8 | E 8 | E 8 | SE 7 | ESE 8 | ESE 8 | ESE 8 | ESE 8 | ENE 9 | S 9 | SSE 9 | SE 9 | SE 9 | SE 9 | SE 10 | SE 10 | SE 10 | SE 10 |
Wave Graph  | |||||||||||||||||||||
 kJ | 256 | 211 | 171 | 134 | 130 | 196 | 177 | 908 | 264 | 250 | 202 | 90 | 1412 | 1032 | 525 | 397 | 314 | 292 | 196 | 196 | 117 |
Wind (km/h) | |||||||||||||||||||||
Wind State on-shore cross-onshore cross-shore cross-offshore off-shore glassy | cross-off | cross-off | cross-off | cross-off | glassy | off | glassy | cross-on | cross | cross-off | cross-off | cross-off | cross-off | cross-on | cross-off | cross | cross-on | cross-off | glassy | cross | cross-off |
High Tide | 2:52PM0.74m | 2:33AM0.82m | 3:14PM0.70m | 3:07AM0.80m | 3:37PM0.65m | 3:45AM0.75m | 4:01PM0.59m | 4:28AM0.68m | 4:25PM0.53m | 5:22AM0.59m | 4:44PM0.46m | 11:45PM0.33m | 11:44AM0.63m | 00:04AM0.36m | |||||||
Low Tide | 9:04AM-0.02m | 9:14PM0.24m | 9:40AM0.04m | 9:42PM0.24m | 10:20AM0.13m | 10:09PM0.25m | 11:11AM0.24m | 10:22PM0.27m | 12:29PM0.35m | 9:01PM0.27m | 8:41AM0.49m | 2:23PM0.43m | 9:02PM0.28m | 9:10PM0.30m | |||||||
 | |  |  | |  |  | | | |  |  | | |  | | | | | |  | |
 | 6:31 | — | — | 6:31 | — | — | 6:30 | — | — | 6:28 | — | — | 6:26 | — | — | 6:26 | — | — | 6:24 | — | — |
 | — | 5:59 | — | — | 5:59 | — | — | 6:00 | — | — | 6:00 | — | — | 6:00 | — | — | 6:00 | — | — | 6:01 | — |
mm | 1 | 4 | 1 | 2 | 4 | 29 | 29 | 13 | 32 | 1 | — | — | — | — | — | — | — | — | — | — | — |
Temp °C | 18 | 19 | 18 | 18 | 18 | 19 | 19 | 19 | 20 | 20 | 20 | 15 | 17 | 17 | 14 | 20 | 20 | 15 | 19 | 19 | 15 |
Feels °C | 17 | 19 | 17 | 18 | 20 | 20 | 20 | 20 | 21 | 16 | 14 | 8 | 14 | 14 | 12 | 17 | 16 | 12 | 17 | 15 | 12 |
Swell 1 Height (m) Direction Period (s) | ENE 8 | ENE 8 | ENE 8 | E 8 | E 8 | E 8 | SE 7 | ESE 8 | ESE 8 | ESE 8 | ESE 8 | ENE 9 | SSE 9 | SE 9 | SE 9 | SE 9 | SE 9 | SE 10 | SE 10 | SE 10 | SE 10 |
| kJ | 256 | 211 | 171 | 134 | 130 | 196 | 173 | 643 | 264 | 250 | 202 | 90 | 921 | 743 | 525 | 397 | 314 | 292 | 196 | 196 | 117 |
Swell 2 Height (m) Direction Period (s) | SE 10 | SSE 10 | SSE 10 | SSE 5 | SSE 5 | S 6 | E 8 | ENE 9 | ENE 9 | ENE 8 | ENE 9 | ESE 8 | ENE 10 | ENE 10 | ENE 9 | E 9 | E 9 | ENE 9 | ENE 9 | NE 5 | ENE 9 |
| kJ | 25 | 10 | 9 | 14 | 16 | 16 | 177 | 106 | 116 | 43 | 116 | 62 | 77 | 75 | 48 | 40 | 39 | 26 | 25 | 6 | 26 |
Swell 3 Height (m) Direction Period (s) | — | — | SSE 10 | SSE 10 | SSE 10 | SE 9 | — | — | — | — | N 4 | — | — | — | ENE 9 | S 12 | S 11 | S 9 | NE 4 | ENE 8 | NE 5 |
| kJ | — | — | 9 | 9 | 9 | 3 | — | — | — | — | 1 | — | — | — | 75 | 3 | 2 | 2 | 7 | 24 | 4 |
Wind waves Height (m) Direction Period (s) | SSW 3 | S 3 | S 4 | — | — | — | — | ESE 8 | — | — | — | S 9 | S 9 | SSE 9 | — | N 3 | NE 4 | NE 5 | — | SW 7 | S 4 |
| kJ | 1 | 2 | 9 | — | — | — | — | 908 | — | — | — | 1010 | 1412 | 1032 | — | 5 | 15 | 22 | — | 2 | 4 |
Nearest Offshore or Glassy | |||||||||||||||||||||
Distance (km) | 15 | 25 | 0 | 0 | 0 | 0 | 0 | 16 | 9 | 0 | 71 | 15 | 10 | 13 | 0 | 9 | 16 | 0 | 0 | 38 | 21 |
Best forecast wave conditions in Santa Catarina - Sul | |||||||||||||||||||||
Best forecast wave conditions in Brazil | |||||||||||||||||||||
Header Global | |||||||||||||||||||||
- Map Icons:
Break
Live Wave Height (m)
Live Wind Speed (km/h)
Surf Rating (10 Max)
Ocean Swells (m)- Wind Speed (km/h)
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 Siriu 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 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.
Nearest