S
M
T
W
T
F
S
30
88°
66°
31
89°
70°
1
90°
71°
2
90°
71°
3
89°
70°
4
89°
70°
5
88°
69°
6
88°
69°
7
89°
68°
8
90°
70°
9
90°
70°
10
89°
69°
11
89°
69°
12
85°
68°
13
79°
68°
14
81°
67°
15
82°
68°
16
83°
67°
17
85°
65°
18
79°
61°
19
76°
59°
20
77°
58°
21
81°
63°
22
83°
59°
23
75°
55°
24
81°
62°
25
76°
57°
26
81°
62°
27
82°
64°
28
83°
65°
29
79°
59°
30
80°
50°
1
73°
49°
2
71°
51°
3
71°
50°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Louisville
Louisville's September 2026 forecast shows daily high temperatures ranging from 71° to 90°, with overnight lows between 49° and 71°. The average high for September is 83° with an average low of 64°. 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 Louisville. See also: October | November | December.
