In the southern Brazilian cities of Porto Alegre and Curitiba, the subtropical climate is similar to parts of the U.S. and Europe with frosts occurring with some frequency. In this region temperatures in winter can fall below freezing.
In subtropical climate we have all the four seasons (and not the dry/wet two-season pattern you can find in tropical weather). It'll be late Autumn during the event: it's still Autumn-dry, but turning cold as the Sun moves towards the equador.
You can check weather information from Weather Channel WebSite, here is a summary of the weather we can expect from May 26th to June 6th (DebConf4 + 5th FISL days):
- Low Average: 11C (52F)
- High Average: 20C (68F)
- Rain: 36mm (May: 94mm; Jun: 132mm)
- Sunrise: ~ 7:15
- Sunset: ~ 17:30