S
M
T
W
T
F
S
30
73°
52°
31
73°
48°
1
77°
56°
2
75°
58°
3
78°
64°
4
75°
60°
5
69°
54°
6
70°
51°
7
76°
50°
8
69°
50°
9
69°
51°
10
70°
49°
11
65°
45°
12
74°
61°
13
76°
52°
14
67°
42°
15
67°
60°
16
72°
56°
17
70°
50°
18
67°
52°
19
68°
48°
20
62°
48°
21
67°
47°
22
68°
50°
23
66°
53°
24
67°
44°
25
59°
39°
26
60°
42°
27
59°
49°
28
64°
45°
29
59°
40°
30
60°
47°
1
64°
47°
2
60°
44°
3
64°
46°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Saint-Hyacinthe
Saint-Hyacinthe's September 2026 forecast shows daily high temperatures ranging from 59° to 76°, with overnight lows between 39° and 61°. The average high for September is 65° 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 Saint-Hyacinthe. See also: October | November | December.
