August in Gronau averages a daily high of 23.5°C with nights around 11.9°C. Expect roughly 13.3 wet days totalling 77.9mm. Generally workable, with some weather to plan around.
Across the year, the best time to visit Gronau is May–September.
Based on TWENTHE, NL (11.3km), 1995–2024. 30 years of August data.