August in Piracicaba is the sunniest month of the year. In August, the weather in Piracicaba is typically warm. Average daily high temperature in August is about 26 degrees above zero. On average, Piracicaba has 20 sunny, 10 partly cloudy, and 1 rainy day in August. The rains are usually light. August as well as June and July is considered the most comfortable time to visit Piracicaba.