S
M
T
W
T
F
S
26
64°
39°
27
68°
41°
28
59°
41°
29
63°
39°
30
66°
46°
1
75°
46°
2
69°
54°
3
62°
49°
4
62°
45°
5
58°
45°
6
56°
42°
7
57°
43°
8
60°
46°
9
62°
48°
10
59°
47°
11
60°
46°
12
60°
45°
13
59°
46°
14
57°
40°
15
61°
47°
16
62°
48°
17
63°
47°
18
64°
47°
19
63°
46°
20
60°
45°
21
60°
44°
22
61°
43°
23
60°
44°
24
62°
44°
25
59°
42°
26
59°
43°
27
61°
48°
28
62°
49°
29
66°
49°
30
65°
44°
31
60°
44°
1
59°
43°
2
59°
43°
3
60°
45°
4
60°
44°
5
61°
44°
6
61°
45°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in Harpenden
Harpenden's May 2026 forecast shows daily high temperatures ranging from 56° to 75°, with overnight lows between 40° and 54°. The average high for May is 61° with an average low of 45°. 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 Harpenden. See also: June | July | August.
