S
M
T
W
T
F
S
29
45°
38°
30
48°
35°
1
55°
29°
2
47°
37°
3
46°
32°
4
56°
29°
5
47°
33°
6
49°
41°
7
51°
36°
8
56°
30°
9
52°
33°
10
44°
35°
11
46°
38°
12
50°
36°
13
53°
36°
14
48°
37°
15
50°
35°
16
55°
28°
17
55°
26°
18
43°
25°
19
45°
25°
20
42°
34°
21
45°
35°
22
53°
36°
23
51°
36°
24
52°
35°
25
50°
30°
26
46°
25°
27
41°
29°
28
44°
28°
29
47°
24°
30
44°
24°
31
42°
34°
1
51°
18°
2
54°
15°
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 41° to 56°, with overnight lows between 15° and 41°. The average high for December is 49° with an average low of 31°. 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.
