September in Cayo Coco is the cloudiest month of the year. In September, the weather in Cayo Coco is typically hot. Average daily high temperature in September is about 28 degrees above zero. On average, Cayo Coco has 22 rainy, 5 sunny, 2 cloudy, and 1 partly cloudy day in September. The rains are usually heavy. September as well as June, July, August, and October is considered the most uncomfortable time to visit Cayo Coco.