S
M
T
W
T
F
S
30
72°
60°
31
73°
57°
1
71°
54°
2
67°
51°
3
70°
52°
4
69°
53°
5
70°
52°
6
68°
49°
7
74°
55°
8
73°
55°
9
73°
54°
10
67°
53°
11
71°
53°
12
73°
52°
13
67°
51°
14
69°
51°
15
71°
52°
16
71°
52°
17
70°
51°
18
70°
47°
19
59°
44°
20
60°
48°
21
66°
49°
22
64°
48°
23
65°
45°
24
58°
43°
25
57°
40°
26
57°
40°
27
58°
44°
28
58°
43°
29
61°
44°
30
62°
46°
1
64°
39°
2
55°
39°
3
54°
42°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Gravenhurst
Gravenhurst's September 2026 forecast shows daily high temperatures ranging from 54° to 74°, with overnight lows between 39° and 60°. The average high for September is 66° with an average low of 49°. 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 Gravenhurst. See also: October | November | December.
