Climate almanac
Wilmington
Illinois, United States · 41.31°, -88.15°
What is the weather like in Wilmington in September?
In September, Wilmington is typically 79°F (26°C) during the day and 59°F (15°C) at night. The month brings about 2.9 in (74 mm) of precipitation in total.
- Average high79°F (26°C)
- Average low59°F (15°C)
- Precipitation2.9 in (74 mm)
- Clear or mostly clear days15
- Based on2016-2025 daily ERA5 reanalysis data (10-year normals)