S
M
T
W
T
F
S
26
57°
40°
27
68°
46°
28
64°
51°
29
56°
39°
30
54°
36°
1
49°
33°
2
56°
30°
3
69°
46°
4
81°
44°
5
61°
48°
6
57°
38°
7
58°
36°
8
65°
36°
9
74°
45°
10
65°
39°
11
53°
38°
12
69°
37°
13
58°
40°
14
65°
38°
15
75°
48°
16
83°
63°
17
85°
58°
18
80°
67°
19
79°
59°
20
59°
45°
21
56°
46°
22
64°
50°
23
67°
53°
24
77°
55°
25
82°
62°
26
86°
62°
27
85°
53°
28
72°
50°
29
76°
54°
30
75°
54°
31
74°
55°
1
74°
57°
2
76°
59°
3
80°
61°
4
80°
60°
5
79°
62°
6
76°
61°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in Mount Prospect
Mount Prospect's May 2026 forecast shows daily high temperatures ranging from 72° to 86°, with overnight lows between 50° and 62°. The average high for May is 78° with an average low of 58°. 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 Mount Prospect. See also: June | July | August.
