S
M
T
W
T
F
S
26
63°
39°
27
67°
48°
28
62°
49°
29
58°
38°
30
57°
35°
1
52°
34°
2
57°
29°
3
68°
43°
4
80°
43°
5
58°
45°
6
58°
37°
7
61°
32°
8
67°
35°
9
71°
43°
10
63°
41°
11
60°
42°
12
67°
48°
13
57°
38°
14
62°
46°
15
71°
50°
16
75°
54°
17
78°
57°
18
77°
54°
19
72°
55°
20
75°
57°
21
76°
56°
22
73°
50°
23
74°
54°
24
76°
56°
25
78°
57°
26
79°
58°
27
79°
58°
28
78°
57°
29
79°
58°
30
77°
57°
31
73°
53°
1
70°
52°
2
70°
58°
3
76°
59°
4
79°
59°
5
78°
58°
6
77°
56°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in Wheaton
Wheaton's May 2026 forecast shows daily high temperatures ranging from 57° to 79°, with overnight lows between 38° and 59°. The average high for May is 73° with an average low of 53°. 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 Wheaton. See also: June | July | August.