S
M
T
W
T
F
S
26
64°
36°
27
68°
34°
28
72°
39°
29
68°
36°
30
68°
45°
1
73°
48°
2
77°
52°
3
70°
54°
4
68°
50°
5
63°
52°
6
52°
46°
7
61°
45°
8
66°
45°
9
72°
41°
10
72°
45°
11
55°
43°
12
54°
39°
13
55°
45°
14
56°
40°
15
59°
40°
16
60°
39°
17
63°
47°
18
63°
45°
19
67°
50°
20
71°
50°
21
73°
52°
22
75°
53°
23
77°
54°
24
76°
54°
25
75°
52°
26
76°
53°
27
64°
47°
28
63°
48°
29
64°
47°
30
65°
47°
31
65°
48°
1
66°
48°
2
72°
54°
3
74°
56°
4
76°
57°
5
76°
57°
6
75°
56°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in Bonn
Bonn's May 2026 forecast shows daily high temperatures ranging from 56° to 77°, with overnight lows between 39° and 57°. The average high for May is 69° with an average low of 50°. 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 Bonn. See also: June | July | August.