S
M
T
W
T
F
S
31
66°
39°
1
65°
44°
2
75°
42°
3
83°
48°
4
87°
51°
5
85°
57°
6
72°
57°
7
73°
51°
8
79°
47°
9
85°
54°
10
89°
56°
11
88°
68°
12
89°
69°
13
84°
60°
14
89°
62°
15
77°
52°
16
75°
52°
17
77°
55°
18
69°
60°
19
74°
56°
20
74°
53°
21
73°
52°
22
70°
54°
23
72°
53°
24
73°
55°
25
73°
56°
26
70°
55°
27
74°
54°
28
73°
53°
29
72°
52°
30
72°
54°
1
73°
53°
2
73°
55°
3
74°
60°
4
74°
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 69° to 89°, with overnight lows between 52° and 62°. The average high for June is 74° with an average low of 55°. 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.
