S
M
T
W
T
F
S
26
77°
59°
27
81°
55°
28
77°
53°
29
74°
58°
30
80°
58°
31
76°
54°
1
79°
52°
2
74°
52°
3
73°
54°
4
74°
53°
5
74°
52°
6
75°
53°
7
76°
54°
8
79°
56°
9
75°
60°
10
76°
59°
11
77°
59°
12
82°
58°
13
79°
59°
14
81°
53°
15
74°
51°
16
74°
52°
17
75°
52°
18
73°
50°
19
72°
51°
20
73°
51°
21
74°
52°
22
73°
51°
23
71°
57°
24
75°
55°
25
71°
52°
26
76°
59°
27
79°
57°
28
75°
58°
29
80°
56°
30
80°
49°
31
71°
49°
1
70°
48°
2
69°
55°
3
71°
55°
4
75°
48°
5
70°
47°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
August Weather in Cardiff
Cardiff's August 2026 forecast shows daily high temperatures ranging from 69° to 82°, with overnight lows between 47° and 60°. The average high for August is 75° with an average low of 54°. 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 Cardiff. See also: September | October | November.
