Weather on December 9
Longmont, CO
55 Years of Data
Avg High
43°F
Avg Low
16°F
Warmest
2015
55°F avg
Coldest
1978
-6°F avg
About This Date
December 9th in Longmont, CO typically brings chilly winter weather, with average highs around 43°F and lows near 16°F — a 27°F daily swing. Over 55 years of records, the warmest December 9th was in 2015 (55°F average), while the coldest was 1978 (-6°F) — a 61°F range across recorded history. Precipitation has occurred on 13% of recorded December 9th dates, with snow falling 13% of the time (heaviest snowfall: 8.6"). The last decade has been 5.4°F warmer on this date compared to 20-30 years ago.
The last decade has been 5.4°F warmer on this date compared to 20-30 years ago.
Planning for December 9th in Longmont, CO? Bring layers as temperatures can vary throughout the day.
Warming Trend
2.6°F per decade on this date
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 55° | 37° | 46° | — | — |
| 2024 | 54° | 26° | 40° | — | — |
| 2023 | 44° | 21° | 33° | 0.56" | 2.5" |
| 2022 | 46° | 15° | 31° | — | — |
| 2021 | 52° | 22° | 37° | — | — |
| 2020 | 62° | 19° | 41° | — | — |
| 2019 | 52° | 25° | 38° | — | — |
| 2018 | 47° | 18° | 32° | — | — |
| 2017 | 60° | 25° | 42° | — | — |
| 2016 | 48° | 6° | 27° | — | — |
| 2015warmest | 68° | 42° | 55° | — | — |
| 2014 | 47° | 26° | 36° | — | — |
| 2013 | 25° | -6° | 10° | — | — |
| 2012 | 38° | 14° | 26° | — | — |
| 2011 | 40° | 16° | 28° | — | — |
| 2010 | 59° | 37° | 48° | — | — |
| 2009 | 16° | -12° | 2° | — | 0.1" |
| 2008 | 33° | 16° | 24° | 1.5" | 8.6" |
| 2007 | 25° | 7° | 16° | 0.48" | 3.3" |
| 2006 | 57° | 29° | 43° | — | — |
| 2005 | 44° | 10° | 27° | — | — |
| 2004 | 51° | 30° | 41° | — | — |
| 2003 | 34° | 16° | 25° | 0.91" | 2.5" |
| 2002 | 44° | 18° | 31° | — | — |
| 2001 | 50° | 11° | 30° | — | — |
| 2000 | 43° | 24° | 33° | — | — |
| 1999 | 38° | 8° | 23° | 0.1" | — |
| 1998 | 38° | 6° | 22° | — | — |
| 1997 | 42° | 14° | 28° | — | — |
| 1996 | 68° | 37° | 53° | — | — |
| 1995 | 21° | 2° | 11° | — | — |
| 1994 | 33° | 4° | 18° | — | — |
| 1993 | 67° | 22° | 44° | — | — |
| 1992 | 46° | 9° | 27° | — | — |
| 1991 | 43° | 19° | 31° | — | — |
| 1990 | 59° | 24° | 42° | — | — |
| 1989 | 54° | 10° | 32° | — | — |
| 1988 | 25° | -10° | 8° | — | — |
| 1987 | 49° | 19° | 34° | — | — |
| 1986 | 39° | 15° | 27° | 0.58" | 4" |
| 1985 | 28° | 10° | 19° | 1.42" | 6.5" |
| 1984 | 50° | 28° | 39° | — | — |
| 1983 | 51° | 20° | 35° | — | — |
| 1982 | 27° | 11° | 19° | — | — |
| 1981 | 58° | 21° | 39° | — | — |
| 1980 | 43° | 18° | 30° | — | — |
| 1979 | 40° | 23° | 31° | — | — |
| 1978coldest | 7° | -19° | -6° | — | — |
| 1977 | 23° | 0° | 12° | — | — |
| 1976 | 60° | 19° | 40° | — | — |
| 1975 | 50° | 29° | 39° | — | — |
| 1974 | 42° | 14° | 28° | — | — |
| 1973 | 55° | 27° | 41° | — | — |
| 1972 | 4° | -6° | -1° | — | — |
| 1971 | 16° | -5° | 5° | — | — |
55 years of data from LONGMONT 2 ESE