S
M
T
W
T
F
S
26
75°
54°
27
70°
47°
28
60°
45°
29
60°
41°
30
61°
38°
1
60°
37°
2
61°
36°
3
72°
48°
4
82°
53°
5
56°
46°
6
58°
41°
7
69°
39°
8
69°
43°
9
78°
49°
10
69°
38°
11
78°
43°
12
82°
56°
13
74°
47°
14
78°
47°
15
87°
60°
16
85°
65°
17
85°
67°
18
86°
56°
19
65°
45°
20
67°
47°
21
66°
49°
22
72°
54°
23
77°
60°
24
80°
61°
25
77°
61°
26
82°
62°
27
83°
60°
28
82°
61°
29
75°
55°
30
79°
61°
31
81°
63°
1
82°
61°
2
80°
61°
3
73°
56°
4
73°
58°
5
80°
63°
6
78°
63°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in Mercer
Mercer's May 2026 forecast shows daily high temperatures ranging from 65° to 86°, with overnight lows between 45° and 67°. 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 Mercer. See also: June | July | August.
