S
M
T
W
T
F
S
30
75°
48°
31
69°
48°
1
70°
55°
2
74°
56°
3
67°
48°
4
67°
54°
5
68°
47°
6
68°
49°
7
69°
47°
8
67°
48°
9
66°
47°
10
67°
46°
11
65°
44°
12
64°
44°
13
65°
45°
14
68°
50°
15
70°
42°
16
63°
41°
17
59°
40°
18
60°
41°
19
60°
42°
20
61°
42°
21
61°
41°
22
65°
41°
23
66°
48°
24
67°
48°
25
68°
47°
26
65°
48°
27
67°
39°
28
63°
36°
29
56°
38°
30
57°
46°
1
59°
47°
2
62°
47°
3
64°
46°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Louiseville
Louiseville's September 2026 forecast shows daily high temperatures ranging from 56° to 75°, with overnight lows between 36° and 56°. The average high for September is 65° with an average low of 46°. 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 Louiseville. See also: October | November | December.