S
M
T
W
T
F
S
29
58°
45°
30
57°
45°
1
57°
50°
2
61°
46°
3
60°
50°
4
61°
46°
5
59°
43°
6
57°
46°
7
59°
46°
8
62°
45°
9
62°
47°
10
61°
48°
11
62°
48°
12
62°
47°
13
63°
49°
14
62°
47°
15
62°
47°
16
61°
48°
17
62°
46°
18
62°
45°
19
61°
48°
20
61°
44°
21
56°
40°
22
54°
43°
23
53°
44°
24
54°
43°
25
53°
40°
26
52°
39°
27
53°
38°
28
53°
42°
29
54°
44°
30
55°
47°
31
57°
43°
1
59°
44°
2
57°
46°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
December Weather in San Bruno
San Bruno's December 2026 forecast shows daily high temperatures ranging from 52° to 63°, with overnight lows between 38° and 50°. The average high for December is 58° with an average low of 45°. 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 San Bruno. See also: January | February | March.
