Weather on December 31
Boulder, CO
55 Years of Data
About This Date
December 31st in Boulder, CO typically brings chilly winter weather, with average highs around 43°F and lows near 18°F — a 25°F daily swing. Over 55 years of records, the warmest December 31st was in 1980 (50°F average), while the coldest was 1978 (3°F) — a 47°F range across recorded history. Precipitation has occurred on 18% of recorded December 31st dates, with snow falling 22% of the time (heaviest snowfall: 8"). The last decade has been 7.3°F cooler on this date compared to 20-30 years ago.
The last decade has been 7.3°F cooler on this date compared to 20-30 years ago.
Planning for December 31st in Boulder, CO? Bring layers as temperatures can vary throughout the day. Check road conditions if traveling, as snow is possible.
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 64° | 28° | 46° | — | — |
| 2024 | 36° | 21° | 28° | — | — |
| 2023 | 41° | 27° | 34° | — | — |
| 2022 | 50° | 21° | 36° | — | — |
| 2021 | 45° | 16° | 31° | — | — |
| 2020 | 43° | 21° | 32° | — | — |
| 2019 | 52° | 18° | 35° | — | — |
| 2018 | 37° | 7° | 22° | — | — |
| 2017 | 27° | 12° | 19° | 0.03" | 0.1" |
| 2016 | 50° | 22° | 36° | — | — |
| 2015 | 31° | 6° | 18° | — | — |
| 2014 | 31° | -14° | 8° | — | — |
| 2013 | 57° | 29° | 43° | — | — |
| 2012 | 28° | 10° | 19° | 0.03" | 0.1" |
| 2011 | 59° | 33° | 46° | — | — |
| 2010 | 13° | 2° | 7° | 0.33" | 2.2" |
| 2009 | 38° | 14° | 26° | — | — |
| 2008 | 60° | 15° | 38° | — | — |
| 2007 | 32° | 13° | 22° | — | 0.1" |
| 2006 | 35° | 15° | 25° | — | — |
| 2005 | 65° | 29° | 47° | — | — |
| 2004 | 56° | 34° | 45° | — | — |
| 2003 | 45° | 23° | 34° | — | — |
| 2002 | 58° | 24° | 41° | — | — |
| 2001 | 35° | 13° | 24° | — | — |
| 2000 | 39° | 24° | 32° | 0.03" | 0.1" |
| 1999 | 60° | 26° | 43° | — | — |
| 1998 | 43° | 27° | 35° | — | — |
| 1997 | 63° | 24° | 43° | — | — |
| 1996 | 65° | 32° | 48° | — | — |
| 1995 | 42° | 24° | 33° | 0.1" | 0.2" |
| 1994 | 24° | 13° | 18° | 0.81" | 8" |
| 1993 | 53° | 29° | 41° | — | — |
| 1992 | 38° | 14° | 26° | — | — |
| 1991 | 40° | 19° | 29° | — | — |
| 1990 | 52° | 17° | 34° | — | — |
| 1989 | 35° | 0° | 18° | 0.25" | 1" |
| 1988 | 52° | 19° | 35° | — | — |
| 1987 | 28° | 0° | 14° | — | — |
| 1986 | 43° | 28° | 35° | — | — |
| 1985 | 44° | 19° | 32° | — | — |
| 1984 | 43° | 24° | 33° | 0.05" | 0.3" |
| 1983 | 51° | 31° | 41° | — | — |
| 1982 | 40° | 11° | 25° | — | — |
| 1981 | 48° | 26° | 37° | — | — |
| 1980warmest | 62° | 38° | 50° | — | — |
| 1979 | 52° | 16° | 34° | — | — |
| 1978coldest | 11° | -6° | 3° | — | — |
| 1977 | 48° | 16° | 32° | — | — |
| 1976 | 29° | 1° | 15° | — | — |
| 1975 | 45° | 19° | 32° | 0.51" | 3.7" |
| 1974 | 32° | 17° | 25° | — | 0.1" |
| 1973 | 18° | 0° | 9° | 0.18" | 1.8" |
| 1972 | 35° | 14° | 25° | — | — |
| 1971 | 51° | 22° | 36° | — | — |
Boulder, CO Temperature Range by Month
Average monthly highs and lows. The shaded band shows the typical daily temperature range.
Boulder, CO Monthly Precipitation
Average rainfall and snowfall per month, in inches.
Boulder, CO Daily Temperature Calendar
Average daily high temperature for every day of the year. Each cell is the climatological mean for that calendar day across 55 years of NOAA data.
Best Time to Visit Boulder, CO
Boulder, CO has no months that meet our "pleasant" threshold — every season has tradeoffs.