S
M
T
W
T
F
S
26
85°
70°
27
84°
70°
28
85°
69°
29
84°
69°
30
81°
66°
31
77°
63°
1
78°
68°
2
75°
68°
3
77°
67°
4
81°
69°
5
82°
69°
6
82°
68°
7
77°
65°
8
76°
67°
9
76°
68°
10
77°
68°
11
79°
68°
12
81°
68°
13
82°
69°
14
83°
68°
15
82°
69°
16
84°
62°
17
82°
60°
18
75°
58°
19
73°
58°
20
74°
59°
21
75°
58°
22
75°
59°
23
76°
59°
24
75°
61°
25
78°
66°
26
80°
59°
27
75°
59°
28
73°
58°
29
75°
63°
30
78°
66°
31
79°
57°
1
75°
57°
2
73°
56°
3
72°
61°
4
75°
65°
5
79°
56°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
August Weather in Chicago
Chicago's August 2026 forecast shows daily high temperatures ranging from 72° to 85°, with overnight lows between 56° and 70°. The average high for August is 78° 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 Chicago. See also: September | October | November.
