S
M
T
W
T
F
S
26
84°
60°
27
84°
63°
28
75°
61°
29
74°
66°
30
80°
63°
31
84°
59°
1
82°
60°
2
76°
65°
3
76°
63°
4
83°
60°
5
86°
54°
6
87°
64°
7
84°
67°
8
81°
65°
9
81°
67°
10
81°
63°
11
81°
60°
12
76°
60°
13
78°
57°
14
77°
55°
15
74°
53°
16
78°
51°
17
79°
61°
18
80°
58°
19
77°
60°
20
74°
54°
21
77°
50°
22
80°
50°
23
75°
60°
24
73°
55°
25
73°
57°
26
77°
58°
27
78°
58°
28
70°
47°
29
75°
55°
30
77°
57°
31
74°
58°
1
78°
62°
2
76°
59°
3
75°
58°
4
79°
60°
5
72°
54°
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 70° to 79°, with overnight lows between 47° and 62°. The average high for August is 76° with an average low of 57°. 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.
