In August, the weather in Manzanillo is typically hot. Average daily high temperature in August is about 30 degrees above zero. On average, Manzanillo has 26 rainy, 2 cloudy, 2 partly cloudy, and 1 sunny day in August. The rains are usually heavy. August as well as June, July, September, and October is considered the most uncomfortable time to visit Manzanillo.