S
M
T
W
T
F
S
30
90°
64°
31
87°
65°
1
86°
67°
2
90°
66°
3
87°
67°
4
83°
66°
5
83°
62°
6
84°
63°
7
89°
66°
8
87°
66°
9
87°
65°
10
86°
65°
11
86°
64°
12
88°
64°
13
87°
65°
14
85°
64°
15
84°
64°
16
81°
63°
17
86°
65°
18
85°
64°
19
81°
63°
20
80°
62°
21
79°
61°
22
80°
57°
23
81°
55°
24
80°
54°
25
82°
55°
26
81°
60°
27
77°
60°
28
76°
57°
29
76°
58°
30
77°
58°
1
75°
51°
2
75°
49°
3
73°
48°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Philadelphia
Philadelphia's September 2026 forecast shows daily high temperatures ranging from 73° to 90°, with overnight lows between 48° and 67°. The average high for September is 83° with an average low of 61°. AccuWeather's monthly forecast extends further ahead than any other source, with day-by-day RealFeel® Temperatures giving a complete picture of how September weather will actually feel in Philadelphia. See also: October | November | December.
