Indianapolis in September
8.1out of 10
Yes, a good time to go
Warm and comfortable: highs around 25°C. Some rain: about 8 rainy days.
25°CAvg high
14°CAvg low
8Rainy days (72 mm)
12:15 hDaylight
07:32Sunrise · 19:46 Sunset
Why this score
- Warm and comfortable: highs around 25°C
- Some rain: about 8 rainy days
What to wear and pack
- T-shirts and light layers
How reliable is the forecast?
Rain in September varies a lot between years (±3.4 rainy days), so check the forecast closer to your trip. Averages cover 30 years (1991–2020). Individual days can differ a lot.
Year at a glance
Weather by month
| Month | Avg high | Avg low | Rainfall | Rainy days | Humidity | Sunshine | Score |
|---|---|---|---|---|---|---|---|
| January | 3°C | -5°C | 79 mm | 10 | – | – | 4.2 |
| February | 5°C | -4°C | 68 mm | 9 | – | – | 4.9 |
| March | 11°C | 1°C | 96 mm | 11 | – | – | 5.7 |
| April | 18°C | 7°C | 121 mm | 12 | – | – | 6.6 |
| May | 23°C | 13°C | 121 mm | 14 | – | – | 7.1 |
| June | 28°C | 18°C | 108 mm | 12 | – | – | 7.4 |
| July | 29°C | 20°C | 91 mm | 12 | – | – | 7.5 |
| August | 28°C | 19°C | 72 mm | 9 | – | – | 7.9 |
| September | 25°C | 14°C | 72 mm | 8 | – | – | 8.1 |
| October | 19°C | 8°C | 82 mm | 9 | – | – | 7.4 |
| November | 11°C | 2°C | 87 mm | 9 | – | – | 6.1 |
| December | 5°C | -2°C | 78 mm | 10 | – | – | 4.7 |
Frequently asked questions
How hot is Indianapolis in September?
Daytime highs average 25°C and nights about 14°C.
When is the best time to visit Indianapolis?
The best months are September, August, July.