December in Lille averages a daily high of 7.3°C with nights around 2.4°C. Expect roughly 15.2 wet days totalling 69.2mm. A hard month to visit for comfort alone.
Across the year, the best time to visit Lille is May–September.
Based on LILLE LESQUIN, FR (7.7km), 1995–2024. 30 years of December data.