April in Leiden averages a daily high of 14.3°C with nights around 4.8°C. Expect roughly 11.5 wet days totalling 45mm. Generally workable, with some weather to plan around.
Across the year, the best time to visit Leiden is May–September.
Based on ROTTERDAM, NL (22.2km), 1995–2024. 30 years of April data.