S
M
T
W
T
F
S
30
73°
63°
31
82°
66°
1
79°
57°
2
76°
54°
3
80°
60°
4
79°
61°
5
80°
61°
6
81°
56°
7
72°
56°
8
72°
56°
9
71°
53°
10
72°
54°
11
69°
48°
12
68°
47°
13
67°
48°
14
66°
49°
15
74°
51°
16
71°
50°
17
72°
51°
18
70°
50°
19
67°
49°
20
71°
50°
21
72°
50°
22
71°
49°
23
71°
50°
24
72°
51°
25
72°
50°
26
70°
50°
27
71°
49°
28
71°
49°
29
69°
48°
30
69°
49°
1
68°
49°
2
69°
48°
3
67°
46°
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 66° to 81°, with overnight lows between 46° and 61°. The average high for September is 72° 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.
