S
M
T
W
T
F
S
29
56°
47°
30
59°
38°
1
67°
36°
2
57°
34°
3
56°
31°
4
53°
35°
5
54°
40°
6
59°
44°
7
58°
45°
8
61°
41°
9
53°
37°
10
66°
46°
11
68°
39°
12
Hist. Avg.
58°
38°
13
Hist. Avg.
57°
37°
14
Hist. Avg.
57°
37°
15
Hist. Avg.
57°
37°
16
Hist. Avg.
57°
37°
17
Hist. Avg.
57°
37°
18
Hist. Avg.
56°
36°
19
Hist. Avg.
56°
36°
20
Hist. Avg.
56°
36°
21
Hist. Avg.
56°
36°
22
Hist. Avg.
56°
36°
23
Hist. Avg.
56°
36°
24
Hist. Avg.
56°
36°
25
Hist. Avg.
56°
36°
26
Hist. Avg.
55°
35°
27
Hist. Avg.
55°
35°
28
Hist. Avg.
55°
35°
29
Hist. Avg.
55°
35°
30
Hist. Avg.
55°
35°
31
Hist. Avg.
55°
35°
1
Hist. Avg.
56°
36°
2
Hist. Avg.
56°
36°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
December Weather in Sunnyvale
Sunnyvale's December 2026 forecast shows daily high temperatures ranging from 53° to 68°, with overnight lows between 31° and 47°. The average high for December is 59° with an average low of 39°. 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 Sunnyvale. See also: January | February | March.
