Is Philadelphia hot in September?
Days are typically warm at 26.5°C, while nights average 17.4°C.
United States · 1991–2020 normal
Philadelphia in
September.
Typical September weather in Philadelphia: 26.5°C by day, 17.4°C at night, 116 mm of rain over 7.5 wet days. These are measured 1991–2020 station normals, not a forecast.
Typical high26.5°C
Typical low17.4°C
Rain116 mm
Wet days7.5
In the year-round weather comparison, September scores 72 out of 100 (May leads the year at 80). Daylight is calculated as 12 h 24 from latitude 39.95°.
September at a glance
What is Philadelphia like in September?
Plain answers from the measured climate record—not a forecast or a promise about a particular trip.
Does it rain much?
The measured monthly average is 116 mm across about 8 wet days.
How much daylight is there?
There are about 12 h 24 between sunrise and sunset at mid-month, calculated from the place latitude.
Is September a good time to visit?
September ranks 2 of 12 in our weather comparison; May ranks first.
The evidence behind this page
One month,
from the same station.
- Place identity
- GeoNames 4560349
- NOAA station
- USC00366886 · PHILA FRANKLIN INST
- Station distance
- 1 km from the place centre
- Coverage
- Strong coverage · 27 usable years
- Important limit
- Historical climate is not a forecast. Nearby stations can miss mountains, coasts, and local microclimates.
Next step
Choose your month.
Then plan the details.
The weather comparison for Philadelphia is based on climate evidence, not payments from travel companies. Flight, accommodation and activity links will be clearly labelled when they are added; there are no booking offers on this page today.
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