S
M
T
W
T
F
S
30
83°
63°
31
83°
62°
1
80°
63°
2
80°
63°
3
81°
62°
4
82°
63°
5
79°
58°
6
80°
58°
7
85°
60°
8
82°
55°
9
82°
54°
10
81°
60°
11
78°
54°
12
82°
54°
13
83°
60°
14
83°
52°
15
78°
51°
16
75°
52°
17
76°
51°
18
78°
52°
19
82°
52°
20
82°
53°
21
81°
57°
22
82°
57°
23
81°
54°
24
78°
53°
25
80°
51°
26
80°
56°
27
79°
56°
28
77°
55°
29
79°
55°
30
79°
54°
1
78°
54°
2
78°
53°
3
76°
52°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Johnson City
Johnson City's September 2026 forecast shows daily high temperatures ranging from 75° to 85°, with overnight lows between 51° and 63°. The average high for September is 80° with an average low of 56°. 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 Johnson City. See also: October | November | December.
