S
M
T
W
T
F
S
30
92°
74°
31
92°
72°
1
91°
71°
2
88°
70°
3
89°
69°
4
90°
70°
5
90°
73°
6
88°
71°
7
87°
68°
8
87°
68°
9
88°
67°
10
87°
67°
11
88°
68°
12
87°
67°
13
86°
66°
14
85°
66°
15
86°
67°
16
87°
66°
17
86°
69°
18
89°
70°
19
86°
68°
20
84°
68°
21
Hist. Avg.
85°
63°
22
Hist. Avg.
85°
62°
23
Hist. Avg.
84°
62°
24
Hist. Avg.
84°
62°
25
Hist. Avg.
84°
61°
26
Hist. Avg.
84°
61°
27
Hist. Avg.
83°
61°
28
Hist. Avg.
83°
60°
29
Hist. Avg.
83°
60°
30
Hist. Avg.
82°
60°
1
Hist. Avg.
82°
59°
2
Hist. Avg.
82°
59°
3
Hist. Avg.
82°
58°
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 84° to 92°, with overnight lows between 66° and 74°. The average high for September is 88° with an average low of 69°. 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.
