S
M
T
W
T
F
S
26
81°
62°
27
83°
61°
28
83°
62°
29
84°
63°
30
82°
61°
31
82°
63°
1
83°
63°
2
80°
61°
3
81°
66°
4
82°
63°
5
82°
60°
6
82°
60°
7
81°
65°
8
81°
67°
9
82°
65°
10
86°
67°
11
86°
68°
12
85°
64°
13
87°
64°
14
86°
61°
15
80°
62°
16
82°
61°
17
79°
60°
18
80°
64°
19
81°
66°
20
82°
66°
21
86°
59°
22
81°
58°
23
80°
60°
24
79°
63°
25
78°
59°
26
79°
59°
27
79°
58°
28
80°
57°
29
78°
58°
30
78°
58°
31
80°
63°
1
82°
60°
2
77°
58°
3
79°
56°
4
77°
56°
5
78°
62°
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 77° to 87°, with overnight lows between 56° and 68°. 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.
