S
M
T
W
T
F
S
30
80°
66°
31
80°
58°
1
79°
57°
2
75°
56°
3
74°
61°
4
77°
65°
5
82°
57°
6
81°
55°
7
73°
55°
8
74°
62°
9
75°
62°
10
76°
60°
11
73°
61°
12
71°
59°
13
72°
54°
14
71°
52°
15
70°
53°
16
70°
57°
17
71°
59°
18
77°
60°
19
77°
60°
20
78°
59°
21
77°
56°
22
73°
57°
23
69°
51°
24
70°
50°
25
67°
50°
26
67°
49°
27
Hist. Avg.
72°
54°
28
Hist. Avg.
72°
54°
29
Hist. Avg.
71°
53°
30
Hist. Avg.
71°
53°
1
Hist. Avg.
70°
53°
2
Hist. Avg.
70°
52°
3
Hist. Avg.
70°
52°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
September Weather in Forest Park
Forest Park's September 2026 forecast shows daily high temperatures ranging from 67° to 82°, with overnight lows between 49° and 66°. The average high for September is 74° with an average low of 57°. 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 Forest Park. See also: October | November | December.
