S
M
T
W
T
F
S
26
70°
31°
27
58°
48°
28
55°
42°
29
72°
40°
30
78°
38°
1
75°
45°
2
79°
49°
3
86°
43°
4
72°
44°
5
68°
52°
6
58°
50°
7
67°
47°
8
62°
45°
9
72°
39°
10
68°
48°
11
75°
45°
12
81°
40°
13
58°
49°
14
59°
46°
15
51°
41°
16
59°
37°
17
64°
35°
18
69°
42°
19
63°
46°
20
68°
49°
21
79°
40°
22
76°
48°
23
66°
47°
24
69°
49°
25
56°
45°
26
63°
46°
27
72°
47°
28
80°
50°
29
65°
44°
30
64°
41°
31
67°
45°
1
72°
46°
2
73°
47°
3
72°
50°
4
73°
48°
5
74°
48°
6
68°
49°
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 56° to 80°, with overnight lows between 41° and 50°. The average high for May is 69° with an average low of 47°. 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.
