S
M
T
W
T
F
S
30
83°
63°
31
89°
58°
1
90°
59°
2
93°
55°
3
94°
55°
4
96°
57°
5
97°
59°
6
93°
61°
7
94°
64°
8
89°
60°
9
82°
56°
10
92°
50°
11
93°
51°
12
77°
53°
13
97°
52°
14
86°
64°
15
76°
56°
16
82°
50°
17
81°
62°
18
89°
57°
19
84°
54°
20
76°
54°
21
77°
46°
22
85°
49°
23
73°
56°
24
79°
57°
25
73°
52°
26
87°
46°
27
88°
53°
28
73°
55°
29
75°
55°
30
71°
54°
1
76°
50°
2
84°
42°
3
87°
45°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Johnstown
Johnstown's September 2026 forecast shows daily high temperatures ranging from ° to °, with overnight lows between ° and °. The average high for September is ° with an average low of °. AccuWeather's monthly forecast extends further ahead than any other source, with day-by-day RealFeel® Temperatures giving a complete picture of how September weather will actually feel in Johnstown. See also: October | November | December.
