S
M
T
W
T
F
S
26
61°
42°
27
59°
42°
28
59°
41°
29
60°
42°
30
61°
42°
1
60°
44°
2
58°
39°
3
57°
40°
4
58°
40°
5
58°
41°
6
59°
41°
7
58°
40°
8
58°
42°
9
59°
45°
10
59°
45°
11
60°
46°
12
63°
47°
13
66°
47°
14
66°
46°
15
65°
48°
16
66°
47°
17
67°
48°
18
66°
48°
19
64°
47°
20
62°
47°
21
62°
46°
22
61°
45°
23
61°
48°
24
62°
49°
25
62°
49°
26
63°
47°
27
63°
50°
28
64°
49°
29
63°
51°
30
64°
50°
31
64°
49°
1
67°
51°
2
69°
51°
3
67°
46°
4
66°
46°
5
66°
47°
6
67°
47°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in Cardiff
Cardiff's May 2026 forecast shows daily high temperatures ranging from 57° to 69°, with overnight lows between 39° and 51°. The average high for May is 62° with an average low of 46°. AccuWeather's monthly forecast extends further ahead than any other source, with day-by-day RealFeel® Temperatures giving a complete picture of how May weather will actually feel in Cardiff. See also: June | July | August.
