In September, the weather in Poznan is typically warm. Average daily high temperature in September is about 18 degrees above zero. On average, Poznan has 14 partly cloudy, 8 sunny, 5 cloudy, and 3 rainy days in September. The rains are usually light. September as well as {{month_nom: February}}, and {{month_nom: February}} is considered the most comfortable time to visit Poznan.