March in Castelldefels averages a daily high of 16.6°C with nights around 8.4°C. Expect roughly 5.6 wet days totalling 37.9mm. Comfortable conditions for being outdoors all day.
Across the year, the best time to visit Castelldefels is May–July.
Based on BARCELONA AEROPUERTO, SP (8.5km), 1995–2024. 30 years of March data.