September in Luzern averages a daily high of 19.3°C with nights around 10.8°C. Expect roughly 11.9 wet days totalling 88.6mm. Generally workable, with some weather to plan around.
Across the year, the best time to visit Luzern is May–September.
Based on ZUERICH FLUNTERN, SZ (41.9km), 1995–2024. 30 years of September data.