S
M
T
W
T
F
S
30
78°
52°
31
79°
44°
1
71°
53°
2
86°
65°
3
85°
61°
4
90°
67°
5
89°
66°
6
79°
59°
7
78°
60°
8
79°
55°
9
74°
53°
10
75°
52°
11
74°
50°
12
76°
49°
13
76°
49°
14
73°
46°
15
76°
53°
16
78°
54°
17
80°
53°
18
73°
52°
19
72°
52°
20
77°
51°
21
76°
51°
22
75°
50°
23
76°
53°
24
77°
53°
25
77°
52°
26
74°
51°
27
75°
52°
28
75°
52°
29
74°
51°
30
73°
50°
1
73°
50°
2
72°
49°
3
71°
49°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Custer State Park
Custer State Park's September 2026 forecast shows daily high temperatures ranging from 71° to 90°, with overnight lows between 46° and 67°. The average high for September is 77° with an average low of 53°. 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 Custer State Park. See also: October | November | December.
