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