September in Santander averages a daily high of 22°C with nights around 16°C. Expect roughly 10.4 wet days totalling 87.8mm. Comfortable conditions for being outdoors all day.
Across the year, the best time to visit Santander is June–October.
Based on SANTANDER CMT, SP (2.9km), 1995–2024. 29 years of September data.