S
M
T
W
T
F
S
29
30°
21°
30
33°
23°
1
34°
27°
2
33°
27°
3
36°
26°
4
36°
27°
5
35°
27°
6
38°
26°
7
38°
25°
8
36°
25°
9
37°
24°
10
35°
23°
11
35°
20°
12
32°
17°
13
29°
13°
14
30°
20°
15
31°
16°
16
30°
21°
17
35°
21°
18
35°
20°
19
34°
20°
20
35°
19°
21
35°
19°
22
33°
18°
23
35°
14°
24
34°
8°
25
28°
14°
26
22°
13°
27
24°
16°
28
27°
15°
29
33°
15°
30
31°
17°
31
31°
18°
1
33°
6°
2
34°
1°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
December Weather in Cottage Grove
Cottage Grove's December 2026 forecast shows daily high temperatures ranging from 22° to 38°, with overnight lows between 1° and 27°. The average high for December is 33° with an average low of 19°. AccuWeather's monthly forecast extends further ahead than any other source, with day-by-day RealFeel® Temperatures giving a complete picture of how December weather will actually feel in Cottage Grove. See also: January | February | March.
