May in Center City averages a daily high of 24°C with nights around 13.9°C. Expect roughly 12.3 wet days totalling 111.7mm. 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. 29 years of May data.