August in Rotterdam averages a daily high of 22.8°C with nights around 13.4°C. Expect roughly 12.9 wet days totalling 88.3mm. Generally workable, with some weather to plan around.
Across the year, the best time to visit Rotterdam is May–September.
Based on ROTTERDAM, NL (4.8km), 1995–2024. 30 years of August data.