Climate almanac
Decatur
Indiana, United States · 40.83°, -84.93°
What is the weather like in Decatur in September?
In September, Decatur is typically 79°F (26°C) during the day and 59°F (15°C) at night. The month brings about 2.5 in (62 mm) of precipitation in total.
- Average high79°F (26°C)
- Average low59°F (15°C)
- Precipitation2.5 in (62 mm)
- Clear or mostly clear days13
- Based on2016-2025 daily ERA5 reanalysis data (10-year normals)