August in São João de Meriti is the sunniest month of the year. In August, the weather in São João de Meriti is typically warm. Average daily high temperature in August is about 25 degrees above zero. On average, São João de Meriti has 23 sunny, 5 partly cloudy, and 3 rainy days in August. The rains are usually light. August as well as June and July is considered the most comfortable time to visit São João de Meriti.