S
M
T
W
T
F
S
29
33°
23°
30
36°
25°
1
34°
31°
2
38°
32°
3
38°
30°
4
40°
31°
5
40°
31°
6
44°
30°
7
40°
31°
8
38°
30°
9
37°
28°
10
35°
26°
11
43°
23°
12
39°
22°
13
37°
15°
14
32°
14°
15
29°
17°
16
32°
18°
17
29°
24°
18
34°
26°
19
35°
24°
20
38°
26°
21
37°
26°
22
36°
27°
23
41°
26°
24
43°
19°
25
40°
13°
26
34°
13°
27
28°
21°
28
32°
25°
29
39°
25°
30
39°
29°
31
42°
29°
1
42°
21°
2
44°
15°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
December Weather in Walnut
Walnut's December 2026 forecast shows daily high temperatures ranging from 28° to 44°, with overnight lows between 13° and 32°. The average high for December is 37° with an average low of 24°. 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 Walnut. See also: January | February | March.
