September in La Guaira is the warmest month of the year. In September, the weather in La Guaira is typically warm. Average daily high temperature in September is about 25 degrees above zero. On average, La Guaira has 28 rainy and 2 sunny days in September. The rains are usually heavy. September as well as January, April, May, and June is considered the most uncomfortable time to visit La Guaira.