S
M
T
W
T
F
S
26
64°
39°
27
68°
41°
28
59°
41°
29
63°
39°
30
66°
46°
1
73°
45°
2
70°
46°
3
64°
52°
4
55°
50°
5
61°
46°
6
54°
43°
7
55°
43°
8
61°
43°
9
66°
45°
10
54°
37°
11
50°
36°
12
57°
36°
13
54°
43°
14
54°
41°
15
55°
39°
16
55°
39°
17
59°
43°
18
54°
41°
19
61°
48°
20
66°
50°
21
73°
48°
22
81°
52°
23
79°
59°
24
84°
55°
25
N/A
26
93°
58°
27
76°
51°
28
84°
58°
29
76°
57°
30
79°
56°
31
73°
58°
1
72°
57°
2
69°
51°
3
66°
51°
4
64°
50°
5
64°
49°
6
65°
50°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
May Weather in Welwyn
Welwyn's May 2026 forecast shows daily high temperatures ranging from 64° to 93°, with overnight lows between 49° and 58°. The average high for May is 73° 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 May weather will actually feel in Welwyn. See also: June | July | August.
