Thornton Weather in December
Average highs run from 64°F on December 1 to 59°F on December 31, and lows from 37°F to 33°F. Normal precipitation for the month is 3.44 in over about 7 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
- 61°F
- Average low
- 35°F
- Precipitation
- 3.44 in
- Record high
- 88°FDec 4, 1977
- Record low
- -2°FDec 23, 1989
- Chance of a freeze
- 100%
- Daylight
- 10 h 15 min to 10 h 09 min
- Cloud cover
- 58%
- Humidity
- 78%
- Dew point
- 41°F
- Wind
- 9.8 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 | 64°F | 37°F | 80°F 1982 | 21°F 1979 | 22% | 0% |
| Dec 2 | 64°F | 37°F | 81°F 1995 | 22°F 1985 | 22% | 0% |
| Dec 3 | 64°F | 37°F | 85°F 2005 | 24°F 1985 | 22% | 0% |
| Dec 4 | 63°F | 37°F | 88°F 1977 | 18°F 2006 | 22% | 0% |
| Dec 5 | 63°F | 37°F | 81°F 1995 | 24°F 2006 | 22% | 0% |
| Dec 6 | 63°F | 36°F | 80°F 1966 | 19°F 2005 | 22% | 0% |
| Dec 7 | 63°F | 36°F | 82°F 1966 | 24°F 1984 | 23% | 0% |
| Dec 8 | 62°F | 36°F | 80°F 1977 | 19°F 2006 | 23% | 0% |
| Dec 9 | 62°F | 36°F | 80°F 2007 | 13°F 2005 | 23% | 0% |
| Dec 10 | 62°F | 36°F | 78°F 1983 | 17°F 1978 | 23% | 0% |
| Dec 11 | 62°F | 36°F | 81°F 1996 | 20°F 1966 | 23% | 0% |
| Dec 12 | 61°F | 35°F | 80°F 1990 | 18°F 1962 | 23% | 0% |
| Dec 13 | 61°F | 35°F | 77°F 1996 | 15°F 1989 | 23% | 0% |
| Dec 14 | 61°F | 35°F | 80°F 1975 | 16°F 1985 | 24% | 0% |
| Dec 15 | 61°F | 35°F | 77°F 1995 | 21°F 1963 | 24% | 0% |
| Dec 16 | 61°F | 35°F | 79°F 1977 | 11°F 1989 | 24% | 0% |
| Dec 17 | 60°F | 35°F | 79°F 1990 | 17°F 1979 | 24% | 0% |
| Dec 18 | 60°F | 35°F | 76°F 1970 | 19°F 1979 | 24% | 0% |
| Dec 19 | 60°F | 34°F | 77°F 1977 | 17°F 1996 | 24% | 0% |
| Dec 20 | 60°F | 34°F | 77°F 1978 | 17°F 1996 | 24% | 0% |
| Dec 21 | 60°F | 34°F | 78°F 1984 | 21°F 1989 | 24% | 0% |
| Dec 22 | 59°F | 34°F | 78°F 1970 | 9°F 1983 | 24% | 0% |
| Dec 23 | 59°F | 34°F | 78°F 1996 | -2°F 1989 | 24% | 0% |
| Dec 24 | 59°F | 34°F | 79°F 1964 | 5°F 1989 | 24% | 0% |
| Dec 25 | 59°F | 34°F | 73°F 1971 | 6°F 1983 | 24% | 0% |
| Dec 26 | 59°F | 34°F | 79°F 1988 | 11°F 1983 | 24% | 0% |
| Dec 27 | 59°F | 34°F | 81°F 2005 | 26°F 1983 | 24% | 0% |
| Dec 28 | 59°F | 34°F | 79°F 1984 | 26°F 1999 | 24% | 0% |
| Dec 29 | 59°F | 34°F | 80°F 1984 | 13°F 1983 | 24% | 0% |
| Dec 30 | 59°F | 34°F | 79°F 1984 | 4°F 1983 | 24% | 0% |
| Dec 31 | 59°F | 33°F | 77°F 1964 | 14°F 1976 | 24% | 0% |
Chance of rain
- Chance of a wet day
- Chance of snowfall
Sunrise and sunset
Times for 2026, local time (CST).
- December 1
- sunrise 7:08 AM, sunset 5:23 PM
- December 31
- sunrise 7:25 AM, sunset 5:34 PM
Other months
Sources
Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00415611 (Marlin), public domain. Records: NOAA GHCN-Daily, station USC00413047, 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 2026-09-24. Sun and moon: computed with the NOAA solar equations and Meeus.