May in Kiel averages a daily high of 16.8°C with nights around 7.3°C. Expect roughly 12.4 wet days totalling 56.2mm. Generally workable, with some weather to plan around.
Across the year, the best time to visit Kiel is June–September.
Based on KIEL HOLTENAU, GM (6.1km), 1995–2024. 25 years of May data.