S
M
T
W
T
F
S
26
90°
72°
27
84°
70°
28
85°
66°
29
79°
63°
30
78°
63°
31
81°
68°
1
85°
70°
2
86°
70°
3
85°
69°
4
86°
69°
5
81°
68°
6
82°
69°
7
87°
68°
8
79°
69°
9
85°
67°
10
78°
64°
11
80°
66°
12
82°
69°
13
85°
66°
14
81°
62°
15
77°
61°
16
78°
65°
17
78°
66°
18
81°
68°
19
84°
64°
20
85°
68°
21
85°
64°
22
77°
61°
23
82°
68°
24
78°
65°
25
84°
64°
26
85°
66°
27
83°
58°
28
77°
57°
29
73°
55°
30
75°
58°
31
77°
62°
1
75°
65°
2
80°
57°
3
76°
54°
4
73°
55°
5
72°
54°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
August Weather in Mount Prospect
Mount Prospect's August 2026 forecast shows daily high temperatures ranging from 72° to 90°, with overnight lows between 54° and 72°. The average high for August is 81° with an average low of 64°. AccuWeather's monthly forecast extends further ahead than any other source, with day-by-day RealFeel® Temperatures giving a complete picture of how August weather will actually feel in Mount Prospect. See also: September | October | November.
