S
M
T
W
T
F
S
30
65°
60°
31
66°
59°
1
76°
63°
2
75°
59°
3
76°
58°
4
66°
58°
5
73°
57°
6
74°
55°
7
77°
55°
8
72°
64°
9
75°
64°
10
70°
50°
11
74°
50°
12
77°
59°
13
65°
53°
14
65°
47°
15
71°
54°
16
67°
49°
17
70°
50°
18
58°
46°
19
62°
46°
20
65°
50°
21
54°
48°
22
57°
50°
23
59°
51°
24
60°
51°
25
63°
49°
26
67°
51°
27
66°
54°
28
65°
53°
29
63°
52°
30
62°
53°
1
62°
51°
2
63°
44°
3
59°
50°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Mackinac Island
Mackinac Island's September 2026 forecast shows daily high temperatures ranging from 54° to 67°, with overnight lows between 44° and 54°. The average high for September is 62° with an average low of 51°. 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 Mackinac Island. See also: October | November | December.
