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