McHenry County Weather in December
Average highs run from 30°F on December 1 to 19°F on December 31, and lows from 8°F to -2°F. Normal precipitation for the month is 0.66 in over about 4 wet days.
December day by day
The normal high and low for each date, and the record, in °F.
- Normal low
- Normal high
- Record high
- Record low
December at a glance
- Average high
- 24°F
- Average low
- 2°F
- Precipitation
- 0.66 in
- Snowfall
- 10.0 in
- Record high
- 62°FDec 9, 2015
- Record low
- -36°FDec 23, 1983
- Chance of a freeze
- 100%
- Daylight
- 8 h 39 min to 8 h 25 min
- Cloud cover
- 67%
- Humidity
- 86%
- Dew point
- 12°F
- Wind
- 11.6 mph
Every day of the month
A wet day has at least 0.01 inch of precipitation; snow means at least 0.1 inch of snowfall.
| Date | Normal high | Normal low | Record high | Record low | Chance wet | Chance of snow |
|---|---|---|---|---|---|---|
| Dec 1 | 30°F | 8°F | 58°F 2021 | -19°F 2014 | 11% | 9% |
| Dec 2 | 29°F | 7°F | 56°F 1949 | -17°F 1985 | 11% | 9% |
| Dec 3 | 29°F | 7°F | 53°F 2020 | -17°F 1985 | 11% | 10% |
| Dec 4 | 28°F | 7°F | 58°F 1979 | -21°F 1964 | 11% | 10% |
| Dec 5 | 28°F | 6°F | 53°F 1963 | -20°F 1994 | 11% | 10% |
| Dec 6 | 27°F | 6°F | 55°F 2023 | -23°F 1994 | 11% | 10% |
| Dec 7 | 27°F | 5°F | 53°F 2023 | -20°F 2013 | 11% | 10% |
| Dec 8 | 27°F | 5°F | 55°F 2020 | -23°F 1977 | 11% | 10% |
| Dec 9 | 26°F | 5°F | 62°F 2015 | -27°F 1977 | 11% | 11% |
| Dec 10 | 26°F | 4°F | 56°F 1987 | -21°F 1977 | 12% | 11% |
| Dec 11 | 25°F | 4°F | 50°F 2004 | -18°F 2013 | 12% | 11% |
| Dec 12 | 25°F | 3°F | 51°F 2017 | -15°F 1956 | 12% | 11% |
| Dec 13 | 25°F | 3°F | 50°F 2002 | -19°F 1949 | 12% | 11% |
| Dec 14 | 24°F | 3°F | 55°F 1998 | -23°F 1949 | 12% | 12% |
| Dec 15 | 24°F | 2°F | 51°F 1997 | -23°F 1963 | 12% | 12% |
| Dec 16 | 24°F | 2°F | 54°F 1962 | -20°F 1951 | 12% | 12% |
| Dec 17 | 23°F | 2°F | 56°F 1997 | -22°F 1983 | 12% | 12% |
| Dec 18 | 23°F | 1°F | 51°F 2018 | -28°F 1951 | 12% | 12% |
| Dec 19 | 22°F | 1°F | 51°F 2004 | -31°F 1983 | 12% | 12% |
| Dec 20 | 22°F | 1°F | 50°F 2004 | -32°F 1983 | 12% | 12% |
| Dec 21 | 22°F | 0°F | 49°F 1979 | -25°F 1951 | 12% | 12% |
| Dec 22 | 22°F | 0°F | 51°F 1954 | -30°F 1983 | 12% | 12% |
| Dec 23 | 21°F | 0°F | 47°F 2023 | -36°F 1983 | 12% | 12% |
| Dec 24 | 21°F | 0°F | 47°F 1999 | -28°F 1983 | 12% | 12% |
| Dec 25 | 21°F | -1°F | 48°F 1999 | -21°F 1996 | 12% | 12% |
| Dec 26 | 20°F | -1°F | 49°F 2005 | -23°F 1950 | 12% | 12% |
| Dec 27 | 20°F | -1°F | 50°F 1999 | -25°F 2017 | 12% | 13% |
| Dec 28 | 20°F | -1°F | 51°F 1999 | -20°F 1992 | 12% | 13% |
| Dec 29 | 20°F | -2°F | 52°F 1999 | -24°F 1968 | 12% | 13% |
| Dec 30 | 20°F | -2°F | 44°F 1980 | -28°F 2017 | 12% | 12% |
| Dec 31 | 19°F | -2°F | 45°F 1963 | -30°F 1967 | 12% | 12% |
Chance of rain
- Chance of a wet day
- Chance of snowfall
Sunrise and sunset
Times for 2026, local time (CST).
- December 1
- sunrise 8:12 AM, sunset 4:51 PM
- December 31
- sunrise 8:33 AM, sunset 4:58 PM
Other months
Sources
Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00328792 (Towner 2 Ne), public domain. Records: NOAA GHCN-Daily, station USW00024013, every year on file, quality-flagged values removed. Cloud, humidity, wind and sunshine: NASA POWER (MERRA-2, CERES and GEWEX SRB), 1991-2020. The data was obtained from the National Aeronautics and Space Administration (NASA) Langley Research Center's Prediction Of Worldwide Energy Resources (POWER) project funded through the NASA Earth Science Division: POWER Daily API v2, accessed 2026-09-25. Sun and moon: computed with the NOAA solar equations and Meeus.