July in Troisdorf averages a daily high of 24.8°C with nights around 13.2°C. Expect roughly 13.9 wet days totalling 87.9mm. Generally workable, with some weather to plan around.
Across the year, the best time to visit Troisdorf is May–September.
Based on KOLN BONN, GM (6.3km), 1995–2024. 30 years of July data.