S
M
T
W
T
F
S
30
70°
54°
31
72°
48°
1
71°
56°
2
72°
57°
3
72°
61°
4
69°
55°
5
66°
56°
6
70°
51°
7
73°
53°
8
68°
54°
9
68°
54°
10
67°
51°
11
61°
45°
12
69°
46°
13
72°
58°
14
58°
43°
15
61°
36°
16
69°
55°
17
67°
50°
18
58°
43°
19
60°
37°
20
64°
45°
21
57°
43°
22
57°
38°
23
65°
38°
24
69°
35°
25
72°
39°
26
70°
46°
27
69°
45°
28
65°
43°
29
65°
46°
30
66°
48°
1
65°
50°
2
63°
43°
3
59°
45°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Lac-Castor
Lac-Castor's September 2026 forecast shows daily high temperatures ranging from 59° to 72°, with overnight lows between 35° and 50°. The average high for September is 66° with an average low of 44°. 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 Lac-Castor. See also: October | November | December.
