The temperatures in Naperville in September are comfortable with low of 15°C and and high up to 24°C.
You can expect about 3 to 8 days of rain in Naperville during the month of September. It’s a good idea to bring along your umbrella so that you don’t get caught in poor weather.
Our weather forecast can give you a great sense of what weather to expect in Naperville in September 2025.
If you’re planning to visit Naperville in the near future, we highly recommend that you review the 14 day weather forecast for Naperville before you arrive.
Temperatures
24° / 15°
Rainy Days
4
Snowy Days
0
Dry Days
26
Rainfall
69
mm
Sun Hours
10.5
Hrs