S
M
T
W
T
F
S
30
74°
51°
31
76°
57°
1
74°
59°
2
80°
59°
3
76°
50°
4
74°
49°
5
72°
50°
6
71°
51°
7
73°
57°
8
78°
56°
9
79°
57°
10
80°
52°
11
73°
53°
12
71°
56°
13
71°
48°
14
70°
51°
15
68°
50°
16
69°
48°
17
70°
54°
18
75°
45°
19
68°
47°
20
70°
44°
21
72°
47°
22
68°
51°
23
72°
54°
24
76°
54°
25
74°
53°
26
74°
54°
27
73°
53°
28
76°
49°
29
73°
50°
30
71°
53°
1
73°
50°
2
74°
43°
3
71°
40°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Grand Rapids
Grand Rapids's September 2026 forecast shows daily high temperatures ranging from 68° to 80°, with overnight lows between 40° and 59°. The average high for September is 73° 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 Grand Rapids. See also: October | November | December.
