S
M
T
W
T
F
S
31
87°
67°
1
86°
66°
2
82°
60°
3
79°
53°
4
81°
54°
5
81°
65°
6
76°
65°
7
84°
69°
8
82°
70°
9
89°
69°
10
88°
73°
11
87°
74°
12
83°
67°
13
74°
67°
14
76°
59°
15
78°
58°
16
81°
55°
17
86°
64°
18
83°
66°
19
80°
63°
20
87°
66°
21
89°
69°
22
79°
65°
23
80°
65°
24
82°
66°
25
81°
64°
26
80°
67°
27
84°
70°
28
89°
69°
29
89°
70°
30
88°
67°
1
89°
66°
2
86°
66°
3
89°
65°
4
84°
68°
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 79° to 89°, with overnight lows between 64° and 70°. The average high for June is 85° with an average low of 67°. 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.
