In September, the weather in Thiruvananthapuram is typically warm. Average daily high temperature in September is about 27 degrees above zero. On average, Thiruvananthapuram has 26 rainy, 3 cloudy, and 1 partly cloudy day in September. The rains are usually heavy. September as well as April, May, June, and July is considered the most uncomfortable time to visit Thiruvananthapuram.