May in Bielefeld averages a daily high of 18.3°C with nights around 8.3°C. Expect roughly 13.1 wet days totalling 62.8mm. Generally workable, with some weather to plan around.
Across the year, the best time to visit Bielefeld is May–September.
Based on BAD SALZUFLEN, GM (17km), 1995–2024. 30 years of May data.