April in Lille averages a daily high of 15.1°C with nights around 5.9°C. Expect roughly 11 wet days totalling 42.2mm. Generally workable, with some weather to plan around.
Across the year, the best time to visit Lille is May–September.
Based on LILLE LESQUIN, FR (7.7km), 1995–2024. 30 years of April data.