September in Konstanz averages a daily high of 20.6°C with nights around 11.1°C. Expect roughly 11.4 wet days totalling 69.7mm. Comfortable conditions for being outdoors all day.
Across the year, the best time to visit Konstanz is May–September.
Based on KONSTANZ, GM (2.3km), 1995–2024. 30 years of September data.