Other facts from our historical weather data: Does Piranhas have a dry season? Yes, the months of October and November are very dry. Which is the hottest month in Piranhas? December has an average maximum temperature of 36°C (97°F) and is the hottest month of the year. Which is the coolest month in Piranhas? The coolest month is August with an average maximum temperature of 29°C (84°F). Which is the wettest month in Piranhas? March tops the wettest month list with 53mm (2.1 in) of rainfall. Which is the driest month in Piranhas? October is the driest month with 16mm (0.6 in) of precipitation. 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.