Climate almanac
Ontario
Oregon, United States · 44.03°, -116.96°
What is the weather like in Ontario in September?
In September, Ontario is typically 86°F (30°C) during the day and 57°F (14°C) at night. The month brings about 0.4 in (9 mm) of precipitation in total.
- Average high86°F (30°C)
- Average low57°F (14°C)
- Precipitation0.4 in (9 mm)
- Clear or mostly clear days19
- Based on2016-2025 daily ERA5 reanalysis data (10-year normals)