If you’re looking forward to lots of outings with your partner, take a look at these details about year-round temperatures in Barra Grande: The hottest months are usually September and October, with an average temperature of 28°C, while the coldest months are July and June, with an average of 27°C. The rainiest months in Barra Grande are April, March, February and May, with each month seeing an average of 250 mm of rainfall.