In September, the weather in Kristiansand is typically warm. Average daily high temperature in September is about 15 degrees above zero. On average, Kristiansand has 15 rainy, 7 partly cloudy, 6 sunny, and 2 cloudy days in September. The rains are usually heavy. September as well as January, February, March, and April is considered the most uncomfortable time to visit Kristiansand.