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