S
M
T
W
T
F
S
26
N/A
27
92°
69°
28
94°
71°
29
92°
65°
30
88°
64°
31
89°
69°
1
86°
67°
2
82°
66°
3
83°
67°
4
86°
68°
5
89°
69°
6
87°
68°
7
89°
70°
8
88°
69°
9
87°
70°
10
86°
71°
11
87°
71°
12
87°
70°
13
88°
71°
14
90°
71°
15
88°
70°
16
87°
70°
17
88°
71°
18
87°
70°
19
88°
71°
20
89°
70°
21
85°
70°
22
85°
68°
23
89°
70°
24
91°
70°
25
90°
70°
26
89°
70°
27
90°
72°
28
91°
71°
29
91°
71°
30
90°
70°
31
91°
70°
1
87°
69°
2
86°
68°
3
85°
68°
4
82°
67°
5
83°
69°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
August Weather in Cornwell
Cornwell's August 2026 forecast shows daily high temperatures ranging from 82° to 94°, with overnight lows between 64° and 72°. The average high for August is 88° with an average low of 69°. 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 Cornwell. See also: September | October | November.