S
M
T
W
T
F
S
26
82°
55°
27
70°
61°
28
70°
62°
29
66°
51°
30
64°
44°
1
61°
47°
2
59°
42°
3
70°
40°
4
79°
57°
5
69°
46°
6
61°
46°
7
65°
42°
8
75°
51°
9
78°
55°
10
73°
56°
11
76°
48°
12
83°
48°
13
75°
56°
14
71°
45°
15
81°
51°
16
84°
66°
17
87°
67°
18
85°
67°
19
89°
67°
20
70°
60°
21
70°
60°
22
67°
62°
23
74°
62°
24
78°
62°
25
81°
60°
26
75°
65°
27
83°
69°
28
88°
67°
29
83°
65°
30
87°
69°
31
84°
64°
1
85°
63°
2
82°
58°
3
85°
54°
4
87°
57°
5
87°
59°
6
90°
71°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in Helena
Helena's May 2026 forecast shows daily high temperatures ranging from ° to °, with overnight lows between ° and °. The average high for May is ° with an average low of °. 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 Helena. See also: June | July | August.
