S
M
T
W
T
F
S
30
84°
47°
31
73°
47°
1
72°
52°
2
79°
47°
3
78°
46°
4
70°
42°
5
70°
50°
6
77°
50°
7
80°
40°
8
71°
41°
9
68°
42°
10
68°
40°
11
67°
39°
12
67°
43°
13
70°
45°
14
73°
49°
15
76°
50°
16
78°
48°
17
77°
43°
18
67°
41°
19
66°
47°
20
73°
44°
21
68°
37°
22
70°
33°
23
62°
35°
24
64°
37°
25
70°
39°
26
61°
34°
27
62°
38°
28
67°
39°
29
Hist. Avg.
66°
39°
30
Hist. Avg.
65°
38°
1
Hist. Avg.
65°
38°
2
Hist. Avg.
64°
38°
3
Hist. Avg.
64°
37°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
September Weather in Sun Prairie
Sun Prairie's September 2026 forecast shows daily high temperatures ranging from 61° to 84°, with overnight lows between 33° and 52°. The average high for September is 71° with an average low of 43°. 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 Sun Prairie. See also: October | November | December.
