S
M
T
W
T
F
S
29
41°
21°
30
40°
21°
1
41°
22°
2
42°
24°
3
42°
26°
4
47°
30°
5
48°
33°
6
43°
32°
7
45°
29°
8
39°
28°
9
40°
22°
10
39°
20°
11
54°
36°
12
54°
25°
13
56°
23°
14
50°
20°
15
38°
22°
16
41°
19°
17
38°
25°
18
45°
32°
19
46°
34°
20
53°
34°
21
53°
33°
22
52°
33°
23
51°
34°
24
55°
30°
25
56°
22°
26
55°
19°
27
37°
23°
28
43°
29°
29
49°
32°
30
50°
34°
31
52°
35°
1
52°
32°
2
53°
23°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
December Weather in Union
Union's December 2026 forecast shows daily high temperatures ranging from 37° to 56°, with overnight lows between 19° and 36°. The average high for December is 47° 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 Union. See also: January | February | March.
