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