S
M
T
W
T
F
S
30
75°
51°
31
78°
54°
1
82°
61°
2
84°
61°
3
83°
59°
4
74°
50°
5
75°
50°
6
74°
52°
7
76°
51°
8
77°
57°
9
75°
52°
10
76°
50°
11
75°
51°
12
75°
57°
13
74°
50°
14
72°
47°
15
71°
49°
16
72°
50°
17
73°
51°
18
74°
53°
19
79°
53°
20
80°
48°
21
72°
49°
22
71°
48°
23
68°
48°
24
69°
47°
25
67°
45°
26
68°
44°
27
68°
49°
28
70°
52°
29
74°
50°
30
65°
45°
1
66°
48°
2
Hist. Avg.
70°
49°
3
Hist. Avg.
70°
49°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Forest Park
Forest Park's September 2026 forecast shows daily high temperatures ranging from 65° to 84°, with overnight lows between 44° and 61°. 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 Forest Park. See also: October | November | December.
