S
M
T
W
T
F
S
30
80°
55°
31
76°
52°
1
73°
54°
2
78°
50°
3
72°
49°
4
73°
53°
5
79°
54°
6
80°
47°
7
79°
45°
8
70°
53°
9
77°
52°
10
75°
50°
11
73°
54°
12
77°
52°
13
77°
54°
14
78°
53°
15
79°
49°
16
76°
41°
17
Hist. Avg.
71°
46°
18
Hist. Avg.
70°
45°
19
Hist. Avg.
70°
45°
20
Hist. Avg.
69°
44°
21
Hist. Avg.
69°
44°
22
Hist. Avg.
68°
44°
23
Hist. Avg.
68°
43°
24
Hist. Avg.
67°
43°
25
Hist. Avg.
66°
42°
26
Hist. Avg.
66°
42°
27
Hist. Avg.
65°
42°
28
Hist. Avg.
65°
41°
29
Hist. Avg.
64°
41°
30
Hist. Avg.
64°
40°
1
Hist. Avg.
63°
40°
2
Hist. Avg.
62°
39°
3
Hist. Avg.
62°
39°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
September Weather in Custer State Park
Custer State Park's September 2026 forecast shows daily high temperatures ranging from 70° to 80°, with overnight lows between 41° and 55°. The average high for September is 76° 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 Custer State Park. See also: October | November | December.
