S
M
T
W
T
F
S
29
46°
22°
30
52°
19°
1
48°
18°
2
40°
20°
3
44°
21°
4
45°
22°
5
47°
26°
6
50°
28°
7
50°
30°
8
53°
26°
9
54°
26°
10
50°
25°
11
48°
18°
12
45°
19°
13
37°
18°
14
40°
17°
15
37°
13°
16
37°
11°
17
34°
11°
18
33°
12°
19
34°
12°
20
33°
14°
21
36°
20°
22
40°
23°
23
47°
19°
24
46°
13°
25
40°
6°
26
35°
6°
27
33°
17°
28
33°
9°
29
41°
5°
30
32°
5°
31
28°
9°
1
30°
16°
2
35°
7°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
December Weather in Ulster
Ulster's December 2026 forecast shows daily high temperatures ranging from 28° to 54°, with overnight lows between 5° and 30°. The average high for December is 41° with an average low of 17°. 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 Ulster. See also: January | February | March.
