August in Montego Bay is the hottest month of the year. In August, the weather in Montego Bay is typically hot. Average daily high temperature in August is about 30 degrees above zero. On average, Montego Bay has 14 rainy, 12 sunny, and 5 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 Montego Bay.