Climate almanac
Monticello
Illinois, United States · 40.03°, -88.57°
What is the weather like in Monticello in January?
In January, Monticello is typically 37°F (3°C) during the day and 23°F (-5°C) at night. The month brings about 2.8 in (72 mm) of precipitation in total. Snowfall averages about 4.9 in (125 mm) over the month.
- Average high37°F (3°C)
- Average low23°F (-5°C)
- Precipitation2.8 in (72 mm)
- Clear or mostly clear days7
- Snowfall4.9 in (125 mm)
- Based on2016-2025 daily ERA5 reanalysis data (10-year normals)