S
M
T
W
T
F
S
29
44°
32°
30
43°
32°
1
44°
40°
2
48°
41°
3
49°
37°
4
47°
35°
5
49°
32°
6
50°
32°
7
48°
34°
8
49°
38°
9
50°
36°
10
47°
31°
11
48°
31°
12
48°
32°
13
51°
38°
14
46°
38°
15
52°
37°
16
50°
41°
17
48°
40°
18
49°
39°
19
52°
40°
20
48°
39°
21
48°
40°
22
49°
39°
23
49°
37°
24
47°
33°
25
47°
30°
26
46°
30°
27
41°
29°
28
40°
32°
29
42°
29°
30
42°
34°
31
43°
40°
1
48°
35°
2
48°
33°
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 40° to 52°, with overnight lows between 29° and 41°. The average high for December is 47° with an average low of 35°. 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.
