December in Leganés averages a daily high of 11.4°C with nights around 2.7°C. Expect roughly 7.5 wet days totalling 40.6mm. Generally workable, with some weather to plan around.
Across the year, the best time to visit Leganés is April–May.
Based on MADRID GETAFE, SP (4.6km), 1995–2024. 30 years of December data.