August in Luzern averages a daily high of 23.9°C with nights around 14.5°C. Expect roughly 13.6 wet days totalling 120mm. 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 August data.