September in Louisville averages a daily high of 28.1°C with nights around 16.8°C. Expect roughly 7.6 wet days totalling 103.3mm. Comfortable conditions for being outdoors all day.
Across the year, the best time to visit Louisville is April–May.
Based on LOUISVILLE MCALPINE, KY US (3.8km), 1995–2024. 14 years of September data.