S
M
T
W
T
F
S
29
62°
40°
30
63°
32°
1
48°
27°
2
47°
27°
3
53°
38°
4
57°
36°
5
51°
34°
6
50°
30°
7
47°
25°
8
44°
24°
9
45°
26°
10
47°
31°
11
51°
30°
12
58°
33°
13
52°
33°
14
49°
27°
15
49°
27°
16
47°
28°
17
46°
23°
18
43°
20°
19
42°
17°
20
40°
22°
21
46°
27°
22
52°
25°
23
43°
21°
24
43°
20°
25
44°
25°
26
46°
30°
27
46°
26°
28
45°
23°
29
44°
24°
30
43°
23°
31
45°
19°
1
41°
21°
2
43°
30°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
December Weather in Foster
Foster's December 2026 forecast shows daily high temperatures ranging from 40° to 63°, with overnight lows between 17° and 40°. The average high for December is 48° with an average low of 27°. 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 Foster. See also: January | February | March.
