S
M
T
W
T
F
S
26
56°
43°
27
55°
37°
28
56°
40°
29
55°
36°
30
55°
35°
1
59°
37°
2
56°
36°
3
57°
37°
4
60°
39°
5
66°
46°
6
67°
46°
7
68°
48°
8
69°
49°
9
70°
49°
10
70°
48°
11
60°
43°
12
58°
41°
13
61°
46°
14
61°
46°
15
60°
45°
16
61°
46°
17
60°
44°
18
68°
43°
19
64°
42°
20
64°
43°
21
63°
42°
22
62°
41°
23
63°
44°
24
64°
45°
25
64°
48°
26
65°
53°
27
70°
45°
28
66°
51°
29
69°
55°
30
76°
46°
31
69°
47°
1
66°
50°
2
71°
47°
3
72°
47°
4
71°
55°
5
77°
48°
6
68°
48°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in McHenry
McHenry's May 2026 forecast shows daily high temperatures ranging from 55° to 77°, with overnight lows between 35° and 55°. The average high for May is 64° 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 McHenry. See also: June | July | August.
