December weather in Petersburg, IL
The average temperature in Petersburg in December is 30.9°F (22.6°F–39.1°F). Average precipitation: 1.93 inches. Average snowfall is 4.0 inches.
December is a winter month in Petersburg, and is cooler than the annual average of 52.3°F. Daily temperatures swing about 16.5°F between overnight low and afternoon high. Expect about 8 days with precipitation. Daylight averages about 9h 10m. For travel, December is cold.
Avg High
39.1°F
Avg Low
22.6°F
Precipitation
1.93 in
Snow
4.0 in
December records in Petersburg
| Date | Record High | Record Low | Record Precip |
|---|---|---|---|
| December 1 | 59.0°F (2014) | 16.0°F (2022) | 1.20 in (2006) |
| December 2 | 63.0°F (2018) | 14.0°F (2014) | 0.29 in (2025) |
| December 3 | 62.1°F (2021) | 15.1°F (2024) | 1.04 in (1990) |
| December 4 | 62.1°F (2017) | 10.9°F (2025) | 0.49 in (2012) |
| December 5 | 66.0°F (2017) | 1.0°F (2025) | 1.21 in (1999) |
| December 6 | 57.9°F (2019) | 8.1°F (2025) | 0.50 in (2014) |
| December 7 | 45.0°F (2022) | 14.0°F (2018) | 0.77 in (2004) |
| December 8 | 62.1°F (2023) | 8.1°F (2025) | 0.16 in (2004) |
| December 9 | 63.0°F (2024) | 9.0°F (2025) | 0.72 in (2009) |
| December 10 | 61.0°F (2021) | 14.0°F (2018) | 0.38 in (1992) |
| December 11 | 66.0°F (2020) | 12.9°F (2018) | 0.82 in (2021) |
| December 12 | 55.9°F (2015) | 14.0°F (2024) | 0.60 in (2020) |
| December 13 | 68.0°F (2015) | 10.0°F (2024) | 0.57 in (2001) |
| December 14 | 64.0°F (2015) | -5.1°F (2025) | 1.10 in (2015) |
| December 15 | 60.1°F (2021) | -7.1°F (2025) | 0.88 in (2022) |
| December 16 | 63.0°F (2021) | 3.0°F (2016) | 0.99 in (1992) |
| December 17 | 59.0°F (2024) | 17.1°F (2019) | 0.39 in (2001) |
| December 18 | 48.9°F (2017) | -2.0°F (2016) | 1.54 in (2002) |
| December 19 | 54.0°F (2025) | -6.0°F (2016) | 0.74 in (2002) |
| December 20 | 52.0°F (2018) | -5.1°F (2016) | 0.82 in (2011) |
| December 21 | 52.0°F (2023) | 16.0°F (2016) | 0.83 in (2006) |
| December 22 | 61.0°F (2015) | 17.1°F (2024) | 0.34 in (1990) |
| December 23 | 57.0°F (2015) | -9.9°F (2022) | 2.04 in (1988) |
| December 24 | 60.1°F (2020) | -9.0°F (2022) | 1.28 in (2009) |
| December 25 | 64.9°F (2021) | 3.0°F (2022) | 1.24 in (2009) |
| December 26 | 66.0°F (2019) | 3.9°F (2022) | 1.06 in (2009) |
| December 27 | 64.9°F (2019) | -6.0°F (2017) | 2.18 in (2015) |
| December 28 | 60.1°F (2025) | -7.1°F (2017) | 0.92 in (2008) |
| December 29 | 71.1°F (2025) | 3.0°F (2017) | 1.69 in (2015) |
| December 30 | 64.9°F (2022) | 8.1°F (2017) | 0.73 in (1990) |
| December 31 | 46.0°F (2024) | -0.9°F (2017) | 0.72 in (2018) |