In September, the weather in Kotzebue is typically cold. Average daily high temperature in September is about 7 degrees above zero. On average, Kotzebue has 10 rainy, 8 sunny, 7 partly cloudy, and 5 cloudy days in September. The rains are usually moderate. September as well as January, February, March, and July is considered the most uncomfortable time to visit Kotzebue.