S
M
T
W
T
F
S
26
61°
49°
27
67°
40°
28
70°
37°
29
73°
47°
30
70°
52°
1
65°
40°
2
54°
46°
3
63°
39°
4
78°
39°
5
81°
51°
6
79°
56°
7
66°
50°
8
70°
44°
9
76°
46°
10
82°
55°
11
65°
40°
12
71°
36°
13
75°
41°
14
71°
51°
15
72°
42°
16
83°
47°
17
90°
61°
18
91°
67°
19
91°
67°
20
91°
66°
21
89°
61°
22
64°
57°
23
69°
56°
24
80°
62°
25
81°
71°
26
82°
72°
27
86°
70°
28
83°
59°
29
80°
60°
30
71°
50°
31
68°
51°
1
70°
54°
2
71°
53°
3
77°
55°
4
78°
56°
5
79°
60°
6
83°
62°
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 68° to 86°, with overnight lows between 50° and 72°. The average high for May is 78° with an average low of 59°. 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.
