Climate almanac
Jacksonville
Illinois, United States · 39.73°, -90.23°
What is the weather like in Jacksonville in January?
In January, Jacksonville is typically 37°F (3°C) during the day and 23°F (-5°C) at night. The month brings about 2.4 in (60 mm) of precipitation in total. Snowfall averages about 5.6 in (143 mm) over the month.
- Average high37°F (3°C)
- Average low23°F (-5°C)
- Precipitation2.4 in (60 mm)
- Clear or mostly clear days7
- Snowfall5.6 in (143 mm)
- Based on2016-2025 daily ERA5 reanalysis data (10-year normals)