December weather in Big Rock, IL
The average temperature in Big Rock in December is 28.2°F (20.6°F–35.8°F). Average precipitation: 1.68 inches.
December is a winter month in Big Rock, and is cooler than the annual average of 49.4°F. Daily temperatures swing about 15.2°F between overnight low and afternoon high. Expect about 9 days with precipitation. Daylight averages about 8h 59m. For travel, December is cold.
Avg High
35.8°F
Avg Low
20.6°F
Precipitation
1.68 in
Daylight
8h 59m
December records in Big Rock
| Date | Record High | Record Low | Record Precip |
|---|---|---|---|
| December 1 | 59.0°F (2012) | 3.0°F (2025) | 0.77 in (2018) |
| December 2 | 63.0°F (2012) | 0.1°F (2006) | 0.46 in (2007) |
| December 3 | 70.0°F (2012) | -2.7°F (2006) | 0.57 in (2011) |
| December 4 | 66.0°F (1998) | -14.1°F (2025) | 1.06 in (1999) |
| December 5 | 68.0°F (2001) | -9.9°F (2025) | 0.61 in (1999) |
| December 6 | 59.0°F (1998) | -9.8°F (2007) | 1.06 in (1998) |
| December 7 | 51.1°F (2023) | -9.9°F (2005) | 0.61 in (2004) |
| December 8 | 55.9°F (2023) | -5.8°F (2006) | 0.39 in (2009) |
| December 9 | 53.1°F (2023) | -6.9°F (2013) | 0.89 in (2008) |
| December 10 | 59.0°F (2021) | -12.8°F (2013) | 0.80 in (2003) |
| December 11 | 55.9°F (2021) | -13.9°F (2013) | 0.75 in (2020) |
| December 12 | 59.0°F (2015) | -15.9°F (2013) | 0.62 in (2001) |
| December 13 | 62.1°F (2015) | -13.0°F (2000) | 1.40 in (2015) |
| December 14 | 62.1°F (2015) | -11.7°F (2016) | 1.44 in (2011) |
| December 15 | 66.0°F (2021) | -4.9°F (2010) | 0.36 in (2012) |
| December 16 | 66.0°F (2021) | 3.2°F (2009) | 0.36 in (2023) |
| December 17 | 52.0°F (2006) | -4.0°F (2000) | 0.07 in (2011) |
| December 18 | 55.9°F (2002) | -16.8°F (2016) | 0.48 in (2002) |
| December 19 | 53.1°F (2002) | -17.9°F (2016) | 0.12 in (2024) |
| December 20 | 51.1°F (2015) | -11.0°F (2000) | 0.74 in (2012) |
| December 21 | 54.0°F (2015) | -9.0°F (2000) | 0.68 in (2015) |
| December 22 | 52.0°F (2006) | -13.0°F (2000) | 0.78 in (2006) |
| December 23 | 59.0°F (2015) | -11.0°F (2000) | 0.87 in (2015) |
| December 24 | 54.0°F (2019) | -11.9°F (2000) | 0.73 in (2009) |
| December 25 | 57.9°F (2019) | -15.0°F (2000) | 0.54 in (2023) |
| December 26 | 60.1°F (2019) | -8.9°F (2017) | 0.62 in (2008) |
| December 27 | 57.0°F (2008) | -14.8°F (2017) | 1.73 in (2008) |
| December 28 | 57.0°F (2025) | -9.9°F (2000) | 1.21 in (2015) |
| December 29 | 72.0°F (1998) | -4.9°F (2009) | 0.73 in (2019) |
| December 30 | 59.0°F (2002) | -10.8°F (2017) | 0.30 in (2020) |
| December 31 | 55.0°F (2004) | -6.9°F (2017) | 0.81 in (2018) |