S
M
T
W
T
F
S
29
40°
21°
30
32°
18°
1
33°
23°
2
41°
27°
3
42°
27°
4
41°
26°
5
36°
25°
6
33°
16°
7
30°
15°
8
40°
25°
9
44°
25°
10
43°
24°
11
44°
24°
12
43°
23°
13
44°
24°
14
39°
23°
15
35°
23°
16
39°
14°
17
36°
15°
18
32°
8°
19
31°
16°
20
33°
22°
21
38°
15°
22
37°
18°
23
35°
18°
24
39°
17°
25
35°
23°
26
38°
15°
27
39°
3°
28
33°
9°
29
24°
10°
30
34°
5°
31
30°
18°
1
31°
23°
2
38°
19°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
December Weather in Colstrip
Colstrip's December 2026 forecast shows daily high temperatures ranging from 24° to 44°, with overnight lows between 3° and 27°. The average high for December is 37° 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 Colstrip. See also: January | February | March.