S
M
T
W
T
F
S
29
49°
37°
30
54°
37°
1
48°
32°
2
47°
36°
3
48°
36°
4
51°
31°
5
44°
29°
6
45°
35°
7
41°
35°
8
43°
34°
9
44°
36°
10
50°
35°
11
44°
34°
12
40°
30°
13
43°
27°
14
35°
25°
15
35°
32°
16
39°
33°
17
45°
34°
18
49°
34°
19
45°
33°
20
43°
28°
21
35°
25°
22
39°
32°
23
44°
32°
24
41°
31°
25
34°
19°
26
34°
22°
27
37°
25°
28
36°
20°
29
35°
23°
30
36°
20°
31
35°
15°
1
34°
15°
2
31°
17°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
December Weather in Sumner
Sumner's December 2026 forecast shows daily high temperatures ranging from 31° to 54°, with overnight lows between 15° and 37°. The average high for December is 42° with an average low of 29°. 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 Sumner. See also: January | February | March.
