If you’re looking forward to lots of outings with your partner, take a look at these details about year-round temperatures in Curitiba: The hottest months are usually January and February, with an average temperature of 20°C, while the coldest months are July and June, with an average of 15°C. The rainiest months in Curitiba are January, February, December and October, with each month seeing an average of 221 mm of rainfall.