S
M
T
W
T
F
S
31
78°
62°
1
84°
61°
2
80°
58°
3
76°
65°
4
76°
64°
5
84°
64°
6
88°
65°
7
85°
64°
8
85°
63°
9
89°
62°
10
86°
62°
11
87°
62°
12
83°
60°
13
82°
59°
14
83°
58°
15
76°
56°
16
76°
54°
17
77°
55°
18
77°
57°
19
78°
59°
20
77°
62°
21
82°
64°
22
78°
63°
23
82°
63°
24
82°
64°
25
85°
65°
26
85°
61°
27
82°
64°
28
81°
66°
29
81°
65°
30
80°
66°
1
83°
66°
2
85°
65°
3
86°
63°
4
79°
58°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
June Weather in Alton
Alton's June 2026 forecast shows daily high temperatures ranging from 76° to 89°, with overnight lows between 54° and 66°. The average high for June is 82° with an average low of 62°. AccuWeather's monthly forecast extends further ahead than any other source, with day-by-day RealFeel® Temperatures giving a complete picture of how June weather will actually feel in Alton. See also: July | August | September.
