S
M
T
W
T
F
S
28
101°
82°
29
100°
80°
30
101°
79°
1
100°
79°
2
101°
79°
3
101°
80°
4
102°
80°
5
100°
79°
6
100°
79°
7
96°
80°
8
98°
79°
9
96°
78°
10
95°
79°
11
97°
80°
12
95°
79°
13
91°
77°
14
99°
78°
15
99°
77°
16
101°
78°
17
99°
79°
18
98°
78°
19
99°
79°
20
99°
77°
21
99°
78°
22
98°
79°
23
100°
78°
24
100°
79°
25
99°
79°
26
100°
78°
27
100°
79°
28
98°
76°
29
94°
75°
30
94°
76°
31
95°
77°
1
94°
76°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
July Weather in Alton
Alton's July 2026 forecast shows daily high temperatures ranging from 91° to 101°, with overnight lows between 75° and 80°. The average high for July is 98° with an average low of 78°. AccuWeather's monthly forecast extends further ahead than any other source, with day-by-day RealFeel® Temperatures giving a complete picture of how July weather will actually feel in Alton. See also: August | September | October.
