S
M
T
W
T
F
S
26
60°
41°
27
62°
48°
28
61°
45°
29
52°
40°
30
54°
37°
1
49°
35°
2
48°
39°
3
51°
40°
4
54°
43°
5
56°
44°
6
60°
44°
7
58°
46°
8
60°
44°
9
58°
45°
10
60°
43°
11
60°
44°
12
63°
49°
13
65°
41°
14
56°
39°
15
57°
39°
16
58°
40°
17
59°
43°
18
61°
50°
19
66°
44°
20
59°
42°
21
59°
41°
22
60°
42°
23
61°
43°
24
64°
52°
25
68°
48°
26
63°
46°
27
62°
44°
28
63°
49°
29
69°
53°
30
73°
52°
31
67°
50°
1
70°
53°
2
74°
56°
3
75°
55°
4
75°
50°
5
65°
49°
6
66°
51°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in Markham
Markham's May 2026 forecast shows daily high temperatures ranging from 48° to 75°, with overnight lows between 35° and 56°. The average high for May is 61° with an average low of 45°. AccuWeather's monthly forecast extends further ahead than any other source, with day-by-day RealFeel® Temperatures giving a complete picture of how May weather will actually feel in Markham. See also: June | July | August.
