S
M
T
W
T
F
S
29
51°
20°
30
46°
13°
1
41°
16°
2
35°
24°
3
46°
23°
4
44°
18°
5
44°
22°
6
39°
24°
7
44°
24°
8
42°
22°
9
40°
19°
10
37°
20°
11
42°
16°
12
38°
11°
13
31°
10°
14
30°
14°
15
29°
23°
16
38°
22°
17
Hist. Avg.
31°
13°
18
Hist. Avg.
31°
13°
19
Hist. Avg.
31°
13°
20
Hist. Avg.
30°
12°
21
Hist. Avg.
30°
12°
22
Hist. Avg.
30°
12°
23
Hist. Avg.
30°
12°
24
Hist. Avg.
30°
12°
25
Hist. Avg.
30°
12°
26
Hist. Avg.
30°
12°
27
Hist. Avg.
30°
11°
28
Hist. Avg.
29°
11°
29
Hist. Avg.
29°
11°
30
Hist. Avg.
29°
11°
31
Hist. Avg.
29°
11°
1
Hist. Avg.
29°
11°
2
Hist. Avg.
29°
11°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
December Weather in Walnut
Walnut's December 2026 forecast shows daily high temperatures ranging from 29° to 51°, with overnight lows between 10° and 24°. The average high for December is 40° with an average low of 19°. 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.
