S
M
T
W
T
F
S
26
81°
62°
27
80°
61°
28
81°
61°
29
82°
60°
30
81°
61°
31
81°
63°
1
80°
62°
2
80°
61°
3
81°
67°
4
82°
62°
5
85°
60°
6
81°
61°
7
80°
66°
8
80°
66°
9
85°
67°
10
84°
67°
11
86°
66°
12
87°
64°
13
86°
62°
14
86°
60°
15
79°
61°
16
81°
60°
17
80°
59°
18
79°
61°
19
80°
65°
20
82°
66°
21
86°
59°
22
82°
59°
23
79°
62°
24
78°
64°
25
77°
59°
26
82°
59°
27
79°
60°
28
78°
57°
29
77°
57°
30
78°
58°
31
79°
62°
1
79°
62°
2
82°
61°
3
78°
58°
4
76°
59°
5
75°
61°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
August Weather in Cornwall
Cornwall's August 2026 forecast shows daily high temperatures ranging from 75° to 87°, with overnight lows between 57° and 67°. The average high for August is 81° 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 Cornwall. See also: September | October | November.
