August in Posadas is the windiest month of the year. In August, the weather in Posadas is typically warm. Average daily high temperature in August is about 21 degrees above zero. On average, Posadas has 16 sunny, 10 partly cloudy, 4 rainy, and 1 cloudy day in August. The rains are usually light. August as well as September is considered the most comfortable time to visit Posadas.