S
M
T
W
T
F
S
26
73°
51°
27
68°
49°
28
62°
46°
29
57°
40°
30
57°
35°
1
55°
32°
2
64°
33°
3
73°
51°
4
74°
48°
5
56°
41°
6
47°
33°
7
59°
30°
8
75°
36°
9
63°
39°
10
61°
35°
11
63°
45°
12
75°
48°
13
63°
42°
14
67°
53°
15
74°
55°
16
79°
54°
17
76°
57°
18
77°
57°
19
80°
58°
20
78°
57°
21
84°
61°
22
67°
47°
23
68°
49°
24
69°
50°
25
69°
54°
26
71°
50°
27
74°
53°
28
76°
52°
29
77°
56°
30
79°
59°
31
80°
59°
1
75°
54°
2
77°
61°
3
81°
63°
4
82°
61°
5
76°
58°
6
72°
59°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in Onalaska
Onalaska's May 2026 forecast shows daily high temperatures ranging from 61° to 84°, with overnight lows between 35° and 63°. The average high for May is 74° with an average low of 53°. 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 Onalaska. See also: June | July | August.
