S
M
T
W
T
F
S
29
41°
24°
30
42°
28°
1
45°
32°
2
45°
29°
3
46°
31°
4
49°
34°
5
51°
24°
6
38°
22°
7
38°
28°
8
48°
33°
9
48°
31°
10
43°
32°
11
47°
33°
12
46°
29°
13
40°
25°
14
37°
21°
15
34°
20°
16
34°
21°
17
37°
25°
18
42°
29°
19
46°
30°
20
44°
31°
21
47°
29°
22
38°
26°
23
38°
26°
24
45°
31°
25
33°
16°
26
34°
17°
27
35°
22°
28
34°
28°
29
47°
24°
30
46°
22°
31
37°
19°
1
36°
18°
2
37°
15°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
December Weather in Mendham
Mendham's December 2026 forecast shows daily high temperatures ranging from 33° to 51°, with overnight lows between 15° and 34°. The average high for December is 41° with an average low of 26°. 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 Mendham. See also: January | February | March.
