August in Barra Mansa is the sunniest month of the year. In August, the weather in Barra Mansa is typically warm. Average daily high temperature in August is about 24 degrees above zero. On average, Barra Mansa has 23 sunny, 5 partly cloudy, and 3 rainy days in August. The rains are usually light. August as well as July is considered the most comfortable time to visit Barra Mansa.