S
M
T
W
T
F
S
29
39°
28°
30
44°
30°
1
37°
31°
2
41°
31°
3
43°
30°
4
41°
30°
5
42°
29°
6
48°
30°
7
46°
28°
8
42°
25°
9
36°
24°
10
38°
27°
11
43°
18°
12
36°
12°
13
32°
11°
14
31°
19°
15
36°
12°
16
37°
25°
17
37°
25°
18
38°
22°
19
40°
24°
20
40°
23°
21
39°
25°
22
42°
23°
23
42°
12°
24
39°
9°
25
30°
11°
26
29°
20°
27
36°
22°
28
36°
22°
29
42°
25°
30
42°
25°
31
44°
24°
1
42°
8°
2
42°
6°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
December Weather in Sidney
Sidney's December 2026 forecast shows daily high temperatures ranging from 29° to 48°, with overnight lows between 6° and 31°. The average high for December is 39° with an average low of 22°. 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 Sidney. See also: January | February | March.
