S
M
T
W
T
F
S
29
48°
30°
30
45°
23°
1
35°
15°
2
33°
14°
3
36°
27°
4
38°
28°
5
35°
27°
6
35°
21°
7
33°
18°
8
31°
21°
9
36°
20°
10
40°
26°
11
39°
26°
12
44°
24°
13
42°
27°
14
37°
24°
15
38°
24°
16
39°
22°
17
37°
15°
18
36°
13°
19
34°
9°
20
30°
8°
21
26°
22°
22
36°
20°
23
37°
16°
24
37°
8°
25
32°
21°
26
33°
24°
27
38°
22°
28
38°
21°
29
36°
15°
30
35°
16°
31
32°
5°
1
31°
3°
2
26°
15°
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 26° to 48°, with overnight lows between 3° and 30°. The average high for December is 36° with an average low of 19°. 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.
