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