S
M
T
W
T
F
S
26
86°
68°
27
86°
68°
28
85°
67°
29
85°
67°
30
83°
64°
31
78°
61°
1
80°
65°
2
76°
65°
3
77°
63°
4
82°
67°
5
84°
67°
6
84°
66°
7
78°
63°
8
77°
64°
9
77°
64°
10
80°
64°
11
81°
66°
12
83°
66°
13
84°
67°
14
85°
66°
15
84°
67°
16
86°
62°
17
84°
58°
18
77°
56°
19
75°
56°
20
75°
57°
21
76°
56°
22
77°
57°
23
76°
57°
24
77°
58°
25
79°
61°
26
81°
58°
27
80°
57°
28
75°
56°
29
76°
59°
30
79°
63°
31
80°
55°
1
80°
55°
2
73°
54°
3
74°
59°
4
76°
63°
5
81°
55°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
August Weather in Grayslake
Grayslake's August 2026 forecast shows daily high temperatures ranging from 73° to 86°, with overnight lows between 54° and 68°. The average high for August is 80° 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 August weather will actually feel in Grayslake. See also: September | October | November.
