Weather on June 21
Longmont, CO
55 Years of Data
Avg High
87°F
Avg Low
53°F
Warmest
2017
80°F avg
Coldest
1972
61°F avg
About This Date
June 21st in Longmont, CO typically brings warm summer weather, with average highs around 87°F and lows near 53°F — a 34°F daily swing. Over 55 years of records, the warmest June 21st was in 2017 (80°F average), while the coldest was 1972 (61°F) — a 19°F range across recorded history. Rain or other precipitation has occurred on about 18% of June 21st dates historically, with the wettest June 21st recording 1.32" of rain. The last decade has been 4.9°F warmer on this date compared to 20-30 years ago.
The last decade has been 4.9°F warmer on this date compared to 20-30 years ago.
Planning for June 21st in Longmont, CO? Stay hydrated and seek shade during peak afternoon hours.
Warming Trend
0.6°F per decade on this date
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 100° | 58° | 79° | — | — |
| 2024 | 95° | 61° | 78° | 1.19" | — |
| 2023 | 86° | 53° | 70° | — | — |
| 2022 | 88° | 54° | 71° | — | — |
| 2021 | 82° | 52° | 67° | 0.2" | — |
| 2020 | 86° | 51° | 69° | — | — |
| 2019 | 85° | 50° | 67° | — | — |
| 2018 | 78° | 53° | 66° | — | — |
| 2017warmest | 98° | 63° | 80° | 0.18" | — |
| 2016 | 99° | 56° | 77° | — | — |
| 2015 | 92° | 56° | 74° | — | — |
| 2014 | 86° | 55° | 71° | — | — |
| 2013 | 92° | 57° | 74° | — | — |
| 2012 | 88° | 54° | 71° | — | — |
| 2011 | 76° | 51° | 63° | — | — |
| 2010 | 81° | 54° | 67° | 0.18" | — |
| 2009 | 80° | 50° | 65° | 0.05" | — |
| 2008 | 86° | 49° | 67° | — | — |
| 2007 | 95° | 60° | 78° | — | — |
| 2006 | 89° | 57° | 73° | 0.15" | — |
| 2005 | 89° | 57° | 73° | — | — |
| 2004 | 74° | 51° | 62° | — | — |
| 2003 | 74° | 57° | 65° | — | — |
| 2002 | 85° | 52° | 68° | — | — |
| 2001 | 80° | 48° | 64° | — | — |
| 2000 | 84° | 41° | 63° | — | — |
| 1999 | 93° | 48° | 71° | — | — |
| 1998 | 84° | 46° | 65° | 0.03" | — |
| 1997 | 91° | 50° | 71° | — | — |
| 1996 | 90° | 56° | 73° | — | — |
| 1995 | 89° | 55° | 72° | — | — |
| 1994 | 87° | 54° | 70° | 1.32" | — |
| 1993 | 87° | 51° | 69° | — | — |
| 1992 | 83° | 54° | 68° | 0.84" | — |
| 1991 | 95° | 57° | 76° | — | — |
| 1990 | 84° | 52° | 68° | — | — |
| 1989 | 95° | 50° | 73° | — | — |
| 1988 | 98° | 58° | 78° | — | — |
| 1987 | 85° | 52° | 68° | — | — |
| 1986 | 91° | 54° | 72° | — | — |
| 1985 | 81° | 55° | 68° | — | — |
| 1984 | 84° | 52° | 68° | — | — |
| 1983 | 92° | 56° | 74° | — | — |
| 1982 | 80° | 49° | 64° | — | — |
| 1981 | 96° | 60° | 78° | — | — |
| 1980 | 86° | 48° | 67° | — | — |
| 1979 | 87° | 49° | 68° | — | — |
| 1978 | 95° | 53° | 74° | — | — |
| 1977 | 80° | 56° | 68° | — | — |
| 1976 | 93° | 52° | 72° | — | — |
| 1975 | 83° | 41° | 62° | — | — |
| 1974 | 93° | 53° | 73° | 0.05" | — |
| 1973 | 78° | 47° | 62° | — | — |
| 1972coldest | 74° | 49° | 61° | — | — |
| 1971 | 92° | 54° | 73° | — | — |
55 years of data from LONGMONT 2 ESE