Climate almanac
Naperville
Illinois, United States · 41.79°, -88.15°
What is the weather like in Naperville in September?
In September, Naperville is typically 77°F (25°C) during the day and 58°F (15°C) at night. The month brings about 3.2 in (81 mm) of precipitation in total.
- Average high77°F (25°C)
- Average low58°F (15°C)
- Precipitation3.2 in (81 mm)
- Clear or mostly clear days13
- Based on2016-2025 daily ERA5 reanalysis data (10-year normals)