S
M
T
W
T
F
S
30
77°
62°
31
85°
65°
1
86°
65°
2
83°
64°
3
77°
65°
4
77°
65°
5
75°
59°
6
76°
56°
7
76°
49°
8
72°
58°
9
83°
55°
10
78°
53°
11
78°
60°
12
80°
57°
13
74°
63°
14
84°
60°
15
70°
50°
16
72°
56°
17
73°
52°
18
70°
51°
19
66°
49°
20
67°
49°
21
69°
51°
22
72°
48°
23
74°
53°
24
76°
54°
25
74°
54°
26
76°
54°
27
75°
53°
28
75°
54°
29
72°
52°
30
73°
50°
1
67°
49°
2
66°
50°
3
71°
50°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Lake Wisconsin
Lake Wisconsin's September 2026 forecast shows daily high temperatures ranging from 66° to 84°, with overnight lows between 48° and 63°. The average high for September is 73° 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 Lake Wisconsin. See also: October | November | December.
