S
M
T
W
T
F
S
26
65°
40°
27
67°
52°
28
63°
50°
29
56°
36°
30
56°
33°
1
49°
33°
2
55°
28°
3
64°
41°
4
80°
45°
5
56°
45°
6
58°
38°
7
59°
33°
8
65°
42°
9
74°
44°
10
62°
40°
11
55°
40°
12
76°
39°
13
60°
41°
14
64°
35°
15
73°
46°
16
82°
60°
17
86°
63°
18
80°
64°
19
78°
61°
20
61°
47°
21
62°
48°
22
69°
54°
23
68°
55°
24
74°
56°
25
81°
49°
26
84°
59°
27
87°
57°
28
74°
53°
29
77°
56°
30
74°
54°
31
74°
53°
1
72°
56°
2
78°
56°
3
74°
55°
4
79°
58°
5
83°
63°
6
82°
63°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in Chicago Heights
Chicago Heights's May 2026 forecast shows daily high temperatures ranging from 72° to 87°, with overnight lows between 53° and 63°. The average high for May is 78° with an average low of 57°. 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 Chicago Heights. See also: June | July | August.
