September in Bora-Bora is the windiest month of the year. In September, the weather in Bora-Bora is typically warm. Average daily high temperature in September is about 26 degrees above zero. On average, Bora-Bora has 22 sunny, 4 rainy, and 4 partly cloudy days in September. The rains are usually light. September as well as August is considered the most comfortable time to visit Bora-Bora.