S
M
T
W
T
F
S
26
81°
50°
27
84°
53°
28
82°
66°
29
77°
66°
30
76°
63°
31
83°
61°
1
86°
64°
2
83°
71°
3
80°
63°
4
84°
59°
5
86°
58°
6
90°
72°
7
91°
72°
8
88°
68°
9
88°
65°
10
85°
58°
11
84°
65°
12
85°
64°
13
83°
60°
14
82°
58°
15
81°
57°
16
78°
64°
17
79°
58°
18
80°
57°
19
79°
60°
20
80°
57°
21
80°
59°
22
80°
61°
23
77°
58°
24
77°
57°
25
76°
59°
26
77°
61°
27
80°
61°
28
73°
54°
29
73°
54°
30
75°
60°
31
77°
60°
1
73°
59°
2
79°
60°
3
79°
60°
4
78°
59°
5
77°
59°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
August Weather in Plainfield
Plainfield's August 2026 forecast shows daily high temperatures ranging from 73° to 85°, with overnight lows between 54° and 64°. The average high for August is 78° with an average low of 59°. 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 Plainfield. See also: September | October | November.
