Climate almanac
Monticello
Illinois, United States · 40.03°, -88.57°
What is the weather like in Monticello in August?
In August, Monticello is typically 83°F (28°C) during the day and 66°F (19°C) at night. The month brings about 3.3 in (84 mm) of precipitation in total.
- Average high83°F (28°C)
- Average low66°F (19°C)
- Precipitation3.3 in (84 mm)
- Clear or mostly clear days13
- Based on2016-2025 daily ERA5 reanalysis data (10-year normals)