S
M
T
W
T
F
S
26
67°
42°
27
61°
46°
28
56°
40°
29
64°
34°
30
58°
36°
1
59°
33°
2
71°
27°
3
77°
50°
4
80°
44°
5
61°
38°
6
62°
30°
7
72°
35°
8
83°
45°
9
73°
40°
10
76°
34°
11
89°
38°
12
83°
52°
13
81°
42°
14
85°
49°
15
96°
52°
16
87°
52°
17
84°
61°
18
58°
51°
19
59°
43°
20
59°
39°
21
66°
47°
22
73°
54°
23
75°
50°
24
83°
53°
25
90°
63°
26
91°
59°
27
91°
62°
28
88°
64°
29
84°
63°
30
85°
59°
31
84°
56°
1
84°
57°
2
85°
56°
3
84°
55°
4
87°
58°
5
93°
63°
6
92°
62°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in Onawa
Onawa's May 2026 forecast shows daily high temperatures ranging from 84° to 93°, with overnight lows between 55° and 64°. The average high for May is 87° with an average low of 60°. 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 Onawa. See also: June | July | August.
