May in Jena averages a daily high of 20.5°C with nights around 8.5°C. Expect roughly 12.3 wet days totalling 60.4mm. Comfortable conditions for being outdoors all day.
Across the year, the best time to visit Jena is May–September.
Based on JENA STERNWARTE, GM (0.5km), 1995–2024. 30 years of May data.