Climate almanac
Winthrop Harbor
Illinois, United States · 42.48°, -87.82°
What is the weather like in Winthrop Harbor in September?
In September, Winthrop Harbor is typically 70°F (21°C) during the day and 64°F (18°C) at night. The month brings about 3.0 in (75 mm) of precipitation in total.
- Average high70°F (21°C)
- Average low64°F (18°C)
- Precipitation3.0 in (75 mm)
- Clear or mostly clear days14
- Based on2016-2025 daily ERA5 reanalysis data (10-year normals)