S
M
T
W
T
F
S
29
64°
46°
30
64°
43°
1
63°
47°
2
63°
49°
3
62°
48°
4
58°
48°
5
58°
46°
6
59°
44°
7
58°
47°
8
58°
45°
9
59°
46°
10
58°
43°
11
56°
46°
12
58°
46°
13
60°
48°
14
60°
43°
15
59°
41°
16
57°
43°
17
58°
41°
18
53°
40°
19
54°
38°
20
52°
37°
21
53°
37°
22
53°
40°
23
54°
36°
24
54°
36°
25
52°
37°
26
51°
35°
27
52°
34°
28
53°
37°
29
54°
39°
30
55°
40°
31
59°
39°
1
56°
36°
2
53°
35°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
December Weather in Vallejo
Vallejo's December 2026 forecast shows daily high temperatures ranging from 51° to 64°, with overnight lows between 34° and 49°. The average high for December is 57° with an average low of 42°. 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 Vallejo. See also: January | February | March.
