S
M
T
W
T
F
S
30
59°
47°
31
59°
50°
1
62°
52°
2
64°
51°
3
64°
49°
4
59°
50°
5
59°
48°
6
61°
46°
7
58°
49°
8
59°
50°
9
62°
50°
10
63°
51°
11
64°
51°
12
64°
50°
13
66°
49°
14
64°
47°
15
59°
49°
16
61°
50°
17
64°
50°
18
64°
49°
19
65°
48°
20
65°
49°
21
64°
50°
22
62°
45°
23
59°
44°
24
58°
43°
25
57°
43°
26
58°
44°
27
58°
48°
28
60°
46°
29
64°
42°
30
59°
43°
1
Hist. Avg.
64°
48°
2
Hist. Avg.
64°
48°
3
Hist. Avg.
64°
47°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Caspar
Caspar's September 2026 forecast shows daily high temperatures ranging from 57° to 66°, with overnight lows between 42° and 52°. The average high for September is 61° with an average low of 48°. 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 Caspar. See also: October | November | December.
