September in Hartford averages a daily high of 24.6°C with nights around 13.6°C. Expect roughly 10 wet days totalling 107.4mm. Comfortable conditions for being outdoors all day.
Across the year, the best time to visit Hartford is May–June.
Based on HARTFORD BRAINARD AIRPORT, CT US (4.2km), 1995–2024. 29 years of September data.