September in Acapulco is the rainiest and the cloudiest month of the year. In September, the weather in Acapulco is typically hot. Average daily high temperature in September is about 30 degrees above zero. On average, Acapulco has 21 rainy, 5 cloudy, 3 sunny, and 1 partly cloudy day in September. The rains are usually heavy. September as well as August is considered the most uncomfortable time to visit Acapulco.