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Indianapolis weather in September

Weather in Indianapolis: September

Average day temperature: 77.6°F
Average night temperature: 63.2°F
Number of sunny days: 18 days
Day length: 11.8 - 13.0 hours
Number of rainy days: 1 day
Precipitation totals: 0.5 in.

Air temperature in September, °F

Show year:
2025
2024
2023

The highest day temperature during September of 2025 was 88°F. At the same time the lowest night temperature was 49°F. Daily and nightly averages during September were 80.2°F and 61.1°F.

Sunny, partly cloudy and cloudy days

Mostly all days in September are sunny but cloudy days are also possible.

Precipitation total in September, in.

Precipitation total value in Indianapolis in September is 0.5 in. Other months of the year show relatively similar values.

Wind speed in September, mph

The average wind speed value in September is 6.4 mph It makes September one of the least windy months of the year.

Average sunny hours

This chart shows average number of hours during the day when sunlight can reach the ground. It depends on day length and cloudiness during the day. The average number of sunny hours in September is: 8.8.

Best time for vacation in Indianapolis

Sunniest months:
September 18 days
October 17 days
June 14 days
Warmest months:
July 82.8 °F
August 81.7 °F
June 79.5 °F
Coldest months:
January 33.2 °F
February 37.4 °F
December 40.6 °F
Rainiest months:
May 3 days
March 3 days
January 2 days
Windiest months:
March 9.6 mph
April 9.0 mph
February 8.7 mph

Indianapolis on a weather map

Indianapolis
+54°F
NW 9 mph
Feels like: +52°F
Precip.: 0%
Places in USA:
Name
°F
+55°F
+75°F
+75°F
+61°F
+61°F
+79°F
+77°F
+70°F
+43°F
+66°F
+57°F
+82°F
+82°F
+75°F
+48°F
24 Hours Forecast
Indianapolis
Local time: 16:08
December 24, wednesday
1800
48°F
NW
9 mph
2100
37°F
N
8 mph
December 25, thursday
0000
39°F
N
7 mph
0300
39°F
E
8 mph
0600
41°F
SE
7 mph
0900
41°F
S
7 mph
1200
41°F
SW
9 mph
1500
41°F
SW
7 mph
Units of measurement: °C / °F