S
M
T
W
T
F
S
30
82°
67°
31
87°
68°
1
90°
71°
2
93°
69°
3
86°
69°
4
84°
67°
5
83°
65°
6
81°
63°
7
76°
59°
8
72°
60°
9
75°
59°
10
73°
60°
11
73°
53°
12
71°
54°
13
71°
54°
14
75°
51°
15
77°
57°
16
78°
57°
17
75°
56°
18
76°
57°
19
77°
57°
20
77°
56°
21
76°
57°
22
77°
56°
23
77°
56°
24
76°
55°
25
77°
54°
26
75°
55°
27
76°
54°
28
76°
54°
29
75°
53°
30
74°
53°
1
73°
52°
2
74°
52°
3
74°
51°
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 71° to 93°, with overnight lows between 51° and 71°. The average high for September is 77° with an average low of 57°. 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.
