S
M
T
W
T
F
S
29
44°
32°
30
41°
32°
1
41°
34°
2
43°
22°
3
44°
19°
4
39°
18°
5
32°
17°
6
31°
18°
7
31°
17°
8
32°
15°
9
31°
14°
10
27°
16°
11
27°
16°
12
29°
17°
13
29°
19°
14
30°
24°
15
32°
25°
16
33°
21°
17
36°
24°
18
36°
30°
19
37°
28°
20
36°
27°
21
36°
25°
22
35°
27°
23
35°
20°
24
36°
21°
25
34°
27°
26
35°
20°
27
34°
16°
28
30°
15°
29
33°
22°
30
30°
12°
31
24°
12°
1
Hist. Avg.
33°
21°
2
Hist. Avg.
33°
21°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
December Weather in Rosemont
Rosemont's December 2026 forecast shows daily high temperatures ranging from 24° to 44°, with overnight lows between 12° and 34°. The average high for December is 34° with an average low of 21°. 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 Rosemont. See also: January | February | March.
