S
M
T
W
T
F
S
30
74°
54°
31
77°
59°
1
73°
60°
2
80°
52°
3
74°
49°
4
70°
50°
5
70°
49°
6
71°
54°
7
77°
57°
8
79°
58°
9
80°
56°
10
76°
51°
11
71°
55°
12
73°
52°
13
75°
48°
14
70°
48°
15
68°
46°
16
69°
47°
17
72°
54°
18
76°
44°
19
68°
49°
20
69°
44°
21
69°
50°
22
67°
52°
23
75°
54°
24
76°
52°
25
74°
52°
26
73°
53°
27
74°
52°
28
75°
49°
29
72°
51°
30
71°
52°
1
74°
48°
2
74°
41°
3
71°
39°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Cottage Grove
Cottage Grove's September 2026 forecast shows daily high temperatures ranging from 67° to 80°, with overnight lows between 39° and 60°. 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 Cottage Grove. See also: October | November | December.
