September in Port of Spain is the hottest month of the year. In September, the weather in Port of Spain is typically hot. Average daily high temperature in September is about 29 degrees above zero. On average, Port of Spain has 15 rainy, 12 sunny, and 3 partly cloudy days in September. The rains are usually light. September as well as June, July, and August is considered the most uncomfortable time to visit Port of Spain.