S
M
T
W
T
F
S
30
62°
48°
1
70°
46°
2
67°
44°
3
66°
50°
4
67°
52°
5
70°
46°
6
71°
46°
7
77°
49°
8
80°
51°
9
80°
56°
10
84°
53°
11
82°
56°
12
80°
54°
13
76°
52°
14
74°
49°
15
77°
51°
16
80°
52°
17
70°
52°
18
80°
52°
19
77°
54°
20
66°
51°
21
73°
49°
22
75°
51°
23
63°
54°
24
62°
55°
25
64°
51°
26
57°
51°
27
60°
44°
28
65°
41°
29
73°
43°
30
66°
51°
31
64°
53°
1
62°
51°
2
64°
51°
3
62°
54°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
December Weather in Montclair
Montclair's December 2025 forecast shows daily high temperatures ranging from ° to °, with overnight lows between ° and °. The average high for December is ° with an average low of °. 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 Montclair. See also: January | February | March.
