August in Cayo Largo is the hottest month of the year. In August, the weather in Cayo Largo is typically hot. Average daily high temperature in August is about 29 degrees above zero. On average, Cayo Largo has 13 sunny, 12 rainy, and 6 partly cloudy days in August. The rains are usually moderate. August as well as June, September, and October is considered the most uncomfortable time to visit Cayo Largo.