S
M
T
W
T
F
S
29
59°
37°
30
57°
36°
1
58°
37°
2
62°
36°
3
64°
35°
4
57°
40°
5
61°
49°
6
69°
50°
7
70°
42°
8
71°
36°
9
58°
39°
10
60°
44°
11
65°
46°
12
66°
43°
13
64°
36°
14
64°
34°
15
54°
35°
16
56°
41°
17
61°
46°
18
63°
48°
19
63°
50°
20
68°
49°
21
70°
47°
22
69°
45°
23
66°
36°
24
67°
41°
25
63°
44°
26
65°
45°
27
66°
35°
28
64°
39°
29
54°
33°
30
61°
30°
31
52°
31°
1
51°
41°
2
58°
34°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
December Weather in Summit
Summit's December 2026 forecast shows daily high temperatures ranging from 51° to 71°, with overnight lows between 30° and 50°. The average high for December is 62° with an average low of 40°. 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 Summit. See also: January | February | March.
