S
M
T
W
T
F
S
26
80°
53°
27
83°
62°
28
66°
54°
29
67°
48°
30
66°
41°
1
64°
43°
2
62°
44°
3
75°
42°
4
78°
57°
5
69°
47°
6
64°
44°
7
68°
40°
8
78°
49°
9
82°
56°
10
71°
53°
11
77°
45°
12
82°
51°
13
74°
54°
14
73°
47°
15
82°
54°
16
81°
69°
17
87°
64°
18
79°
65°
19
83°
62°
20
68°
56°
21
68°
55°
22
69°
60°
23
74°
64°
24
80°
59°
25
80°
56°
26
82°
62°
27
83°
66°
28
87°
64°
29
83°
66°
30
84°
63°
31
83°
66°
1
84°
63°
2
82°
58°
3
81°
60°
4
82°
62°
5
87°
66°
6
87°
64°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in Collinsville
Collinsville's May 2026 forecast shows daily high temperatures ranging from 81° to 87°, with overnight lows between 58° and 66°. The average high for May is 84° with an average low of 63°. 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 Collinsville. See also: June | July | August.
