S
M
T
W
T
F
S
26
69°
50°
27
72°
46°
28
73°
49°
29
69°
49°
30
57°
38°
1
66°
32°
2
49°
36°
3
59°
31°
4
73°
45°
5
74°
55°
6
64°
50°
7
58°
41°
8
65°
48°
9
69°
50°
10
75°
47°
11
60°
34°
12
61°
44°
13
61°
46°
14
61°
41°
15
66°
49°
16
67°
54°
17
70°
55°
18
75°
56°
19
76°
57°
20
77°
58°
21
75°
63°
22
66°
52°
23
67°
54°
24
66°
52°
25
68°
52°
26
68°
51°
27
69°
50°
28
69°
50°
29
72°
54°
30
75°
58°
31
72°
58°
1
70°
59°
2
75°
57°
3
77°
59°
4
75°
60°
5
74°
60°
6
75°
59°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in Johnstown
Johnstown's May 2026 forecast shows daily high temperatures ranging from 60° to 77°, with overnight lows between 34° and 63°. The average high for May is 70° with an average low of 53°. 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 Johnstown. See also: June | July | August.
