S
M
T
W
T
F
S
30
89°
66°
31
92°
72°
1
96°
74°
2
95°
75°
3
95°
75°
4
97°
77°
5
95°
74°
6
83°
67°
7
84°
62°
8
89°
66°
9
90°
73°
10
80°
69°
11
84°
64°
12
82°
67°
13
83°
55°
14
75°
61°
15
91°
69°
16
93°
70°
17
86°
66°
18
79°
61°
19
77°
56°
20
69°
54°
21
70°
53°
22
72°
54°
23
75°
53°
24
74°
52°
25
75°
52°
26
78°
57°
27
78°
56°
28
75°
58°
29
75°
57°
30
76°
58°
1
76°
56°
2
75°
55°
3
75°
56°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Indianapolis
Indianapolis's September 2026 forecast shows daily high temperatures ranging from 69° to 93°, with overnight lows between 52° and 70°. The average high for September is 78° with an average low of 58°. 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 Indianapolis. See also: October | November | December.
