Climate almanac
Johnston
Iowa, United States · 41.67°, -93.70°
What is the weather like in Johnston in September?
In September, Johnston is typically 80°F (27°C) during the day and 59°F (15°C) at night. The month brings about 3.5 in (88 mm) of precipitation in total.
- Average high80°F (27°C)
- Average low59°F (15°C)
- Precipitation3.5 in (88 mm)
- Clear or mostly clear days15
- Based on2016-2025 daily ERA5 reanalysis data (10-year normals)