S
M
T
W
T
F
S
29
44°
24°
30
47°
30°
1
50°
36°
2
49°
32°
3
54°
33°
4
54°
33°
5
52°
28°
6
43°
24°
7
43°
32°
8
54°
35°
9
51°
34°
10
49°
35°
11
52°
35°
12
51°
31°
13
45°
28°
14
42°
24°
15
40°
23°
16
40°
23°
17
41°
26°
18
46°
34°
19
53°
33°
20
51°
34°
21
53°
28°
22
41°
26°
23
44°
33°
24
52°
34°
25
40°
20°
26
41°
20°
27
40°
26°
28
41°
30°
29
54°
26°
30
47°
21°
31
41°
21°
1
41°
19°
2
40°
18°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
December Weather in Lanham
Lanham's December 2026 forecast shows daily high temperatures ranging from 40° to 54°, with overnight lows between 18° and 36°. The average high for December is 46° with an average low of 28°. 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 Lanham. See also: January | February | March.