Nazare Big Wave Challenge Gets Yellow Alert, Could Run Saturday in Giant Waves
70-foot plus waves predicted for Portuguese big wave tow surfing competition.
Surf Forecasts:
Siriu surfForecast / Santa Catarina – Sul / Brazil
48hr Weather and Surf, issued 2 am Friday 12 Dec 2025 -03Forecast update in hr min s Forecast update imminent
Siriu surf forecast is for near shore open water. Breaking waves will often be smaller at less exposed spots.
Today's Siriu sea temperature is
23.3° C
(Which is slightly cooler than normal)How big are the waves at Siriu today?
The current surf forecast for Siriu at 7AM is: 2.0m 11s primary swell from a South-southeast direction and 0.8m 10s secondary swell from a East-northeast direction (forecast issued at 02:00am December 12). The wind direction is predicted to be cross-shore.
| Time (-03) & Date | Wave Height | Wave Period |
|---|---|---|
| Morning (12 Dec) | 6ft (1.9m) | 11s |
| Afternoon (12 Dec) | 5ft (1.6m) | 10s |
| Evening (12 Dec) | 4.5ft (1.4m) | 10s |
Table - waves today at Siriu. (Swell directed towards the surf break)
Updates in hr min s Forecast update imminent
Friday 12 | Saturday 13 | Sunday 14 | ||||||||||||||||||||||
| 0 AM | 3 AM | 6 AM | 9 AM | 12 PM | 3 PM | 6 PM | 9 PM | 0 AM | 3 AM | 6 AM | 9 AM | 12 PM | 3 PM | 6 PM | 9 PM | 0 AM | 3 AM | 6 AM | 9 AM | 12 PM | 3 PM | 6 PM | 9 PM | |
Rating (10 max) | ||||||||||||||||||||||||
Swell Height Map |    |    |    | |||||||||||||||||||||
| Wave Height (m) & direction (?) | ||||||||||||||||||||||||
| Period(s) (?) | 12 | 11 | 11 | 11 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 6 | 7 | 7 | 7 | 7 | 7 | 7 | 7 |
Wave (?)Graph  | ||||||||||||||||||||||||
 kJ (?) | 1615 | 1256 | 990 | 783 | 596 | 510 | 442 | 380 | 325 | 325 | 281 | 281 | 240 | 204 | 200 | 168 | 202 | 209 | 211 | 198 | 124 | 128 | 128 | 197 |
Wind (km/h) | ||||||||||||||||||||||||
| Wind State (?) onshore cross-onshore cross-shore cross-offshore offshore glassy | cross- off | cross- off | cross- off | cross- on | cross- on | cross- on | cross- off | cross- off | cross- off | cross- off | cross | cross | cross- on | cross- on | cross- on | cross- on | cross- off | cross | cross- on | cross- on | cross- on | cross- on | cross- on | cross- on |
High Tide / height (m) | 11:39AM 0.52 | 6:27PM 0.54 | 11:27AM 0.50 | 8:49PM 0.52 | 10:53AM 0.51 | |||||||||||||||||||
Low Tide / height (m) | 2:12AM 0.24 | 2:54PM 0.45 | 3:17AM 0.27 | 3:52PM 0.38 | 4:19AM 0.29 | 4:43PM 0.30 | ||||||||||||||||||
Friday 12 | Saturday 13 | Sunday 14 | ||||||||||||||||||||||
| Sunrise | - | - | 5:11 | - | - | - | - | - | - | - | 5:11 | - | - | - | - | - | - | - | 5:11 | - | - | - | - | - |
| Sunset | - | - | - | - | - | - | 7:04 | - | - | - | - | - | - | - | 7:05 | - | - | - | - | - | - | - | 7:06 | - |
 | |  | |  |  | |  |  | | | | | | | | | | | | |  | | | |
Rain (mm) | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | 1 | - | - |
| Temp. °C | 21 | 21 | 21 | 25 | 27 | 25 | 25 | 23 | 23 | 21 | 21 | 23 | 24 | 25 | 24 | 22 | 22 | 21 | 22 | 24 | 26 | 26 | 25 | 23 |
| Feels °C (?) | 22 | 21 | 21 | 25 | 27 | 26 | 27 | 23 | 23 | 19 | 20 | 22 | 23 | 24 | 24 | 23 | 24 | 23 | 24 | 26 | 26 | 26 | 26 | 25 |
- Map Icons:
Break
Live Wave Height (m)
Live Wind Speed (km/h)
Surf Rating (10 Max)
Ocean Swells (m)- Wind Speed (km/h)
Latest Updates
Buy Less, Surf More This Black Friday
Surf-forecast is providing a free, all-access pass to our premium features and 12-day forecasts all weekend.
Quiksilver Teams Up With PrimaLoft® For World’s First Thermal Layering System for a Wetsuit.
Previously used in our snow jackets for mountain conditions, PrimaLoft® technology is making its debut in the surf industry. The aim is to bring mountain-grade warmth to the waves.
Vancouver Island’s Day Of Days With Reed Platenius
Surf-Forecast recently helped the 21-year-old Canadian pro surfer and adventurer score some cold water perfection at home.
Read more
Discover more articles and updates in the Greenroom.
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.
Nearest