September in Trenčín averages a daily high of 21.4°C with nights around 10.3°C. Expect roughly 9.5 wet days totalling 63.9mm. Comfortable conditions for being outdoors all day.
Across the year, the best time to visit Trenčín is April–September.
Based on PIESTANY, LO (34.5km), 1995–2024. 22 years of September data.