Climate almanac
Crystal Lake
Illinois, United States · 42.24°, -88.32°
What is the weather like in Crystal Lake in December?
In December, Crystal Lake is typically 37°F (3°C) during the day and 26°F (-4°C) at night. The month brings about 2.2 in (55 mm) of precipitation in total. Snowfall averages about 4.6 in (117 mm) over the month.
- Average high37°F (3°C)
- Average low26°F (-4°C)
- Precipitation2.2 in (55 mm)
- Clear or mostly clear days5
- Snowfall4.6 in (117 mm)
- Based on2016-2025 daily ERA5 reanalysis data (10-year normals)