Other facts from our historical weather data: Which is the warmest month in Serra Grande (Bahia)? March has an average maximum temperature of 30°C (86°F) and is the warmest month of the year. Which is the coldest month in Serra Grande (Bahia)? The coldest month is August with an average maximum temperature of 26°C (79°F). Which is the wettest month in Serra Grande (Bahia)? April tops the wettest month list with 152mm (6 in) of rainfall. Which is the driest month in Serra Grande (Bahia)? September is the driest month with 81mm (3.2 in) of precipitation. Which is the sunniest month in Serra Grande (Bahia)? March is the sunniest month with an average of 235 hours of sunshine. No idea where to travel to this year? We have a tool that recommends destinations based on your ideal conditions. Find out where to go with our weather planner.