S
M
T
W
T
F
S
29
41°
35°
30
45°
36°
1
45°
34°
2
36°
33°
3
36°
32°
4
39°
30°
5
37°
23°
6
30°
21°
7
31°
30°
8
38°
30°
9
37°
31°
10
38°
32°
11
42°
31°
12
41°
30°
13
36°
24°
14
29°
23°
15
28°
24°
16
32°
27°
17
36°
30°
18
40°
30°
19
40°
29°
20
36°
29°
21
37°
28°
22
30°
27°
23
33°
28°
24
37°
29°
25
30°
23°
26
32°
18°
27
31°
22°
28
30°
24°
29
31°
25°
30
29°
14°
31
29°
15°
1
30°
19°
2
29°
16°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
December Weather in Markham
Markham's December 2026 forecast shows daily high temperatures ranging from 28° to 45°, with overnight lows between 14° and 36°. The average high for December is 35° 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 Markham. See also: January | February | March.
