S
M
T
W
T
F
S
26
86°
56°
27
87°
56°
28
90°
55°
29
84°
53°
30
80°
50°
31
79°
47°
1
81°
51°
2
86°
55°
3
87°
51°
4
89°
47°
5
85°
53°
6
91°
54°
7
92°
55°
8
91°
54°
9
90°
46°
10
82°
44°
11
81°
44°
12
79°
43°
13
78°
45°
14
80°
44°
15
80°
43°
16
78°
43°
17
80°
45°
18
80°
49°
19
83°
48°
20
85°
48°
21
82°
49°
22
82°
42°
23
78°
39°
24
77°
40°
25
78°
41°
26
77°
43°
27
78°
46°
28
84°
44°
29
76°
42°
30
76°
46°
31
78°
48°
1
83°
49°
2
78°
46°
3
75°
40°
4
74°
44°
5
75°
44°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
August Weather in Joliet
Joliet's August 2026 forecast shows daily high temperatures ranging from 74° to 92°, with overnight lows between 39° and 56°. The average high for August is 82° with an average low of 47°. 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 Joliet. See also: September | October | November.
