S
M
T
W
T
F
S
26
50°
36°
27
57°
39°
28
64°
36°
29
61°
36°
30
52°
36°
1
64°
28°
2
73°
28°
3
75°
39°
4
77°
39°
5
46°
32°
6
48°
32°
7
72°
32°
8
72°
46°
9
77°
45°
10
68°
46°
11
86°
46°
12
77°
52°
13
90°
46°
14
88°
55°
15
86°
48°
16
81°
54°
17
73°
48°
18
46°
37°
19
57°
34°
20
57°
40°
21
59°
45°
22
63°
44°
23
73°
49°
24
83°
53°
25
84°
53°
26
79°
52°
27
75°
51°
28
77°
51°
29
81°
53°
30
79°
54°
31
75°
55°
1
77°
50°
2
71°
52°
3
70°
45°
4
73°
52°
5
77°
52°
6
77°
51°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in Union
Union's May 2026 forecast shows daily high temperatures ranging from 57° to 84°, with overnight lows between 40° and 55°. The average high for May is 74° 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 Union. See also: June | July | August.
