S
M
T
W
T
F
S
29
50°
38°
30
56°
37°
1
52°
39°
2
54°
37°
3
49°
31°
4
46°
28°
5
54°
35°
6
54°
34°
7
41°
31°
8
40°
25°
9
40°
23°
10
41°
23°
11
37°
24°
12
37°
24°
13
38°
23°
14
38°
20°
15
37°
25°
16
39°
30°
17
40°
33°
18
45°
31°
19
47°
20°
20
43°
18°
21
38°
18°
22
32°
19°
23
37°
25°
24
37°
20°
25
38°
19°
26
34°
17°
27
34°
18°
28
35°
15°
29
34°
20°
30
37°
27°
31
44°
21°
1
46°
17°
2
34°
14°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
December Weather in Gary
Gary's December 2026 forecast shows daily high temperatures ranging from 32° to 56°, with overnight lows between 14° and 39°. The average high for December is 42° with an average low of 25°. 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 Gary. See also: January | February | March.
