S
M
T
W
T
F
S
30
80°
61°
31
81°
54°
1
78°
52°
2
81°
52°
3
70°
57°
4
81°
52°
5
84°
64°
6
79°
66°
7
72°
56°
8
72°
54°
9
70°
50°
10
82°
51°
11
72°
47°
12
63°
43°
13
61°
46°
14
59°
41°
15
67°
43°
16
66°
44°
17
63°
41°
18
61°
40°
19
61°
42°
20
68°
41°
21
67°
48°
22
71°
49°
23
71°
47°
24
60°
46°
25
68°
46°
26
69°
47°
27
68°
47°
28
68°
45°
29
61°
44°
30
56°
42°
1
56°
41°
2
54°
37°
3
54°
41°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Knox
Knox's September 2026 forecast shows daily high temperatures ranging from 54° to 82°, with overnight lows between 37° and 56°. The average high for September is 65° with an average low of 45°. 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 Knox. See also: October | November | December.
