September in Norrköping averages a daily high of 17.4°C with nights around 8.9°C. Expect roughly 10 wet days totalling 46.1mm. Generally workable, with some weather to plan around.
Across the year, the best time to visit Norrköping is May–September.
Based on NORRKOPING SMHI, SW (2.5km), 1995–2024. 30 years of September data.