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The temperatures in Philadelphia in September are comfortable with low of 17°C and and high up to 26°C.
You can expect about 3 to 8 days of rain in Philadelphia during the month of September. It’s a good idea to bring along your umbrella so that you don’t get caught in poor weather.
Our weather forecast can give you a great sense of what weather to expect in Philadelphia in September 2025.
If you’re planning to visit Philadelphia in the near future, we highly recommend that you review the 14 day weather forecast for Philadelphia before you arrive.
| Month | Temperatures | Rainy Days | Dry Days | Snowy Days | Rainfall | Weather | More details |
|---|---|---|---|---|---|---|---|
| January | 3° / -3° | 5 | 19 | 6 | 49 mm | Awful | Philadelphia in January |
| February | 5° / -2° | 6 | 16 | 6 | 70 mm | Awful | Philadelphia in February |
| March | 10° / 2° | 6 | 21 | 4 | 70 mm | Bad | Philadelphia in March |
| April | 17° / 8° | 5 | 25 | 0 | 63 mm | Good | Philadelphia in April |
| May | 22° / 13° | 6 | 26 | 0 | 77 mm | Good | Philadelphia in May |
| June | 27° / 18° | 5 | 25 | 0 | 88 mm | Perfect | Philadelphia in June |
| July | 30° / 21° | 6 | 25 | 0 | 98 mm | Good | Philadelphia in July |
| August | 29° / 21° | 5 | 26 | 0 | 106 mm | Good | Philadelphia in August |
| September | 26° / 17° | 3 | 27 | 0 | 69 mm | Perfect | Philadelphia in September |
| October | 19° / 12° | 4 | 27 | 0 | 72 mm | Good | Philadelphia in October |
| November | 12° / 5° | 4 | 25 | 1 | 51 mm | Ok | Philadelphia in November |
| December | 7° / 1° | 5 | 22 | 3 | 73 mm | Bad | Philadelphia in December |