S
M
T
W
T
F
S
26
54°
43°
27
68°
38°
28
59°
47°
29
58°
50°
30
62°
39°
1
64°
34°
2
54°
41°
3
62°
36°
4
74°
36°
5
84°
46°
6
70°
55°
7
67°
51°
8
67°
38°
9
66°
49°
10
70°
45°
11
63°
49°
12
70°
41°
13
67°
45°
14
57°
46°
15
71°
50°
16
82°
44°
17
87°
54°
18
96°
66°
19
96°
69°
20
88°
55°
21
68°
49°
22
60°
53°
23
64°
56°
24
72°
58°
25
76°
56°
26
77°
55°
27
77°
57°
28
78°
56°
29
79°
57°
30
81°
56°
31
82°
55°
1
80°
59°
2
77°
60°
3
73°
60°
4
77°
59°
5
74°
56°
6
77°
59°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in Mercersburg
Mercersburg's May 2026 forecast shows daily high temperatures ranging from 60° to 96°, with overnight lows between 49° and 69°. The average high for May is 78° with an average low of 58°. 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 Mercersburg. See also: June | July | August.
