S
M
T
W
T
F
S
29
39°
18°
30
38°
21°
1
37°
20°
2
36°
22°
3
36°
23°
4
36°
22°
5
37°
20°
6
37°
18°
7
35°
18°
8
35°
19°
9
34°
20°
10
35°
21°
11
34°
19°
12
34°
17°
13
33°
17°
14
33°
18°
15
30°
14°
16
31°
10°
17
33°
4°
18
24°
-1°
19
21°
2°
20
20°
-2°
21
16°
0°
22
14°
-3°
23
18°
6°
24
19°
12°
25
29°
13°
26
28°
16°
27
31°
16°
28
32°
17°
29
31°
14°
30
30°
8°
31
29°
7°
1
21°
5°
2
18°
-4°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
December Weather in Byron
Byron's December 2026 forecast shows daily high temperatures ranging from 14° to 39°, with overnight lows between -4° and 23°. The average high for December is 30° with an average low of 13°. 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 Byron. See also: January | February | March.
