S
M
T
W
T
F
S
26
45°
30°
27
46°
30°
28
46°
30°
29
48°
28°
30
57°
37°
1
64°
32°
2
66°
37°
3
57°
39°
4
48°
34°
5
48°
32°
6
50°
28°
7
55°
25°
8
59°
27°
9
59°
32°
10
59°
32°
11
59°
43°
12
52°
43°
13
57°
46°
14
52°
45°
15
63°
43°
16
64°
43°
17
52°
41°
18
66°
41°
19
66°
50°
20
63°
46°
21
63°
48°
22
66°
46°
23
72°
46°
24
64°
54°
25
59°
46°
26
59°
45°
27
55°
49°
28
57°
49°
29
58°
47°
30
61°
51°
31
64°
52°
1
60°
53°
2
60°
53°
3
63°
55°
4
61°
54°
5
62°
56°
6
61°
53°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in Helsinki
Helsinki's May 2026 forecast shows daily high temperatures ranging from 55° to 64°, with overnight lows between 47° and 56°. The average high for May is 60° with an average low of 52°. 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 Helsinki. See also: June | July | August.
