S
M
T
W
T
F
S
26
84°
62°
27
83°
67°
28
76°
67°
29
74°
64°
30
78°
62°
31
83°
65°
1
86°
67°
2
85°
66°
3
84°
65°
4
84°
67°
5
87°
68°
6
85°
67°
7
85°
68°
8
86°
64°
9
86°
67°
10
83°
67°
11
85°
67°
12
81°
68°
13
81°
67°
14
85°
66°
15
82°
64°
16
80°
66°
17
80°
66°
18
79°
65°
19
80°
66°
20
81°
65°
21
80°
64°
22
80°
65°
23
80°
66°
24
84°
59°
25
77°
58°
26
77°
65°
27
81°
66°
28
84°
66°
29
84°
65°
30
82°
61°
31
77°
56°
1
75°
56°
2
74°
57°
3
74°
55°
4
75°
57°
5
76°
63°
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 74° to 87°, with overnight lows between 55° and 68°. The average high for August is 81° with an average low of 64°. 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.
