S
M
T
W
T
F
S
30
77°
54°
31
76°
53°
1
75°
54°
2
77°
57°
3
76°
54°
4
77°
53°
5
77°
51°
6
76°
52°
7
74°
49°
8
75°
50°
9
74°
57°
10
74°
51°
11
73°
49°
12
73°
49°
13
74°
55°
14
77°
52°
15
78°
55°
16
79°
55°
17
80°
54°
18
79°
54°
19
78°
52°
20
77°
46°
21
69°
51°
22
70°
52°
23
74°
52°
24
75°
53°
25
76°
48°
26
74°
43°
27
70°
45°
28
67°
44°
29
67°
44°
30
65°
42°
1
Hist. Avg.
71°
48°
2
Hist. Avg.
70°
48°
3
Hist. Avg.
70°
47°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in West Chester
West Chester's September 2026 forecast shows daily high temperatures ranging from 65° to 80°, with overnight lows between 42° and 57°. The average high for September is 74° with an average low of 51°. 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 West Chester. See also: October | November | December.
