September in Retiro averages a daily high of 26.6°C with nights around 15.7°C. Expect roughly 5 wet days totalling 26.5mm. Comfortable conditions for being outdoors all day.
Across the year, the best time to visit Retiro is May–June.
Based on MADRID RETIRO, SP (0.5km), 1995–2024. 30 years of September data.