S
M
T
W
T
F
S
30
80°
64°
31
83°
64°
1
83°
59°
2
82°
57°
3
81°
61°
4
82°
62°
5
77°
62°
6
78°
61°
7
75°
61°
8
78°
54°
9
75°
52°
10
73°
59°
11
76°
60°
12
80°
59°
13
80°
60°
14
78°
59°
15
79°
61°
16
73°
52°
17
72°
58°
18
Hist. Avg.
75°
55°
19
Hist. Avg.
75°
54°
20
Hist. Avg.
74°
54°
21
Hist. Avg.
74°
53°
22
Hist. Avg.
74°
53°
23
Hist. Avg.
73°
53°
24
Hist. Avg.
73°
52°
25
Hist. Avg.
73°
52°
26
Hist. Avg.
72°
52°
27
Hist. Avg.
72°
51°
28
Hist. Avg.
71°
51°
29
Hist. Avg.
71°
50°
30
Hist. Avg.
70°
50°
1
Hist. Avg.
70°
50°
2
Hist. Avg.
70°
49°
3
Hist. Avg.
69°
49°
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 72° to 83°, with overnight lows between 52° and 64°. The average high for September is 78° with an average low of 59°. 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.
