S
M
T
W
T
F
S
26
82°
57°
27
85°
63°
28
79°
63°
29
69°
60°
30
71°
60°
31
76°
61°
1
79°
62°
2
77°
63°
3
79°
61°
4
78°
62°
5
82°
62°
6
82°
61°
7
80°
63°
8
81°
62°
9
81°
62°
10
81°
62°
11
82°
62°
12
81°
63°
13
81°
62°
14
80°
61°
15
77°
59°
16
78°
61°
17
80°
61°
18
80°
60°
19
78°
60°
20
78°
58°
21
77°
58°
22
77°
60°
23
79°
57°
24
80°
52°
25
71°
51°
26
72°
58°
27
75°
60°
28
80°
60°
29
80°
59°
30
77°
51°
31
71°
50°
1
70°
51°
2
70°
50°
3
71°
49°
4
70°
49°
5
76°
57°
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 69° to 85°, with overnight lows between 49° and 63°. The average high for August is 77° with an average low of 59°. 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.
