Weather on October 21
Longmont, CO
55 Years of Data
Avg High
66°F
Avg Low
33°F
Warmest
2012
61°F avg
Coldest
1990
29°F avg
About This Date
October 21st in Longmont, CO typically brings mild fall weather, with average highs around 66°F and lows near 33°F — a 33°F daily swing. Over 55 years of records, the warmest October 21st was in 2012 (61°F average), while the coldest was 1990 (29°F) — a 32°F range across recorded history. Precipitation has occurred on 18% of recorded October 21st dates, with snow falling 7% of the time (heaviest snowfall: 5.8"). 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 October 21st in Longmont, CO? Great weather for outdoor activities.
Warming Trend
0.7°F per decade on this date
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 61° | 31° | 46° | — | — |
| 2024 | 69° | 45° | 57° | — | — |
| 2023 | 83° | 40° | 61° | — | — |
| 2022 | 81° | 40° | 60° | — | — |
| 2021 | 61° | 30° | 45° | — | — |
| 2020 | 59° | 34° | 46° | — | — |
| 2019 | 51° | 30° | 41° | — | — |
| 2018 | 72° | 34° | 53° | — | — |
| 2017 | 80° | 39° | 60° | — | — |
| 2016 | 76° | 37° | 56° | — | — |
| 2015 | 60° | 44° | 52° | 2.62" | — |
| 2014 | 73° | 44° | 59° | — | — |
| 2013 | 61° | 27° | 44° | 0.03" | — |
| 2012warmest | 72° | 51° | 61° | — | — |
| 2011 | 73° | 39° | 56° | — | — |
| 2010 | 73° | 38° | 55° | — | — |
| 2009 | 45° | 32° | 38° | 0.99" | 0.1" |
| 2008 | 66° | 46° | 56° | 0.15" | — |
| 2007 | 64° | 32° | 48° | 0.2" | 0.1" |
| 2006 | 49° | 29° | 39° | 1.7" | 5.8" |
| 2005 | 61° | 45° | 53° | 0.23" | — |
| 2004 | 74° | 36° | 55° | — | — |
| 2003 | 81° | 40° | 60° | — | — |
| 2002 | 70° | 32° | 51° | — | — |
| 2001 | 57° | 29° | 43° | — | — |
| 2000 | 68° | 28° | 48° | — | — |
| 1999 | 68° | 22° | 45° | — | — |
| 1998 | 50° | 23° | 37° | — | — |
| 1997 | 54° | 35° | 44° | 0.18" | — |
| 1996 | 50° | 19° | 35° | — | — |
| 1995 | 69° | 21° | 45° | — | — |
| 1994 | 65° | 33° | 49° | — | — |
| 1993 | 52° | — | — | — | — |
| 1992 | 80° | 35° | 58° | — | — |
| 1991 | 64° | 34° | 49° | — | — |
| 1990coldest | 42° | 16° | 29° | — | — |
| 1989 | 73° | 26° | 50° | — | — |
| 1988 | 70° | 27° | 48° | — | — |
| 1987 | 52° | 22° | 37° | — | — |
| 1986 | 60° | 41° | 51° | — | — |
| 1985 | 72° | 32° | 52° | — | — |
| 1984 | 35° | 25° | 30° | — | 0.3" |
| 1983 | 62° | 31° | 46° | — | — |
| 1982 | 57° | 25° | 41° | — | — |
| 1981 | 78° | 29° | 53° | — | — |
| 1980 | 68° | 30° | 49° | — | — |
| 1979 | 68° | 40° | 54° | 0.89" | — |
| 1978 | 79° | 39° | 59° | — | — |
| 1977 | 80° | 37° | 59° | — | — |
| 1976 | 59° | 23° | 41° | — | — |
| 1975 | 81° | 33° | 57° | — | — |
| 1974 | 77° | 38° | 57° | — | — |
| 1973 | 76° | 36° | 56° | — | — |
| 1972 | 65° | 34° | 49° | 0.86" | — |
| 1971 | 64° | 29° | 46° | — | — |
55 years of data from LONGMONT 2 ESE