August in Aachen averages a daily high of 22.4°C with nights around 12.7°C. Expect roughly 13.8 wet days totalling 71.2mm. Generally workable, with some weather to plan around.
Across the year, the best time to visit Aachen is June–September.
Based on NIDEGGEN SCHMIDT, GM (26.5km), 1995–2024. 30 years of August data.