September in Center City averages a daily high of 26.7°C with nights around 17.5°C. Expect roughly 8.3 wet days totalling 114.7mm. Comfortable conditions for being outdoors all day.
Across the year, the best time to visit Center City is September–October.
Based on PHILADELPHIA FRANKLIN INSTITUTE, PA US (1.4km), 1995–2024. 30 years of September data.