September in Hessisch Oldendorf is the sunniest month of the year. In September, the weather in Hessisch Oldendorf is typically warm. Average daily high temperature in September is about 17 degrees above zero. On average, Hessisch Oldendorf has 9 sunny, 8 rainy, 8 partly cloudy, and 5 cloudy days in September. The rains are usually light.