S
M
T
W
T
F
S
30
75°
54°
31
74°
54°
1
74°
55°
2
75°
54°
3
74°
53°
4
75°
54°
5
76°
58°
6
75°
59°
7
74°
55°
8
73°
53°
9
72°
53°
10
76°
51°
11
72°
50°
12
72°
50°
13
73°
51°
14
71°
55°
15
77°
57°
16
78°
58°
17
77°
56°
18
77°
49°
19
76°
47°
20
69°
48°
21
68°
54°
22
69°
53°
23
75°
54°
24
74°
55°
25
75°
46°
26
74°
43°
27
67°
44°
28
64°
45°
29
65°
45°
30
65°
43°
1
Hist. Avg.
69°
48°
2
Hist. Avg.
69°
47°
3
Hist. Avg.
69°
47°
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 64° to 78°, with overnight lows between 43° and 59°. The average high for September is 73° with an average low of 52°. 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.
