The temperatures in Joliet in September are comfortable with low of 14°C and and high up to 24°C.
You can expect about 3 to 8 days of rain in Joliet 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 Joliet in September 2025.
If you’re planning to visit Joliet in the near future, we highly recommend that you review the 14 day weather forecast for Joliet before you arrive.
Temperatures
24° / 14°
Rainy Days
6
Snowy Days
0
Dry Days
24
Rainfall
116
mm
Sun Hours
10.2
Hrs
