Weather on June 21
Longmont, CO
55 Years of Data
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.
| 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° | — | — |
Longmont, CO Temperature Range by Month
Average monthly highs and lows. The shaded band shows the typical daily temperature range.
Longmont, CO Monthly Precipitation
Average rainfall and snowfall per month, in inches.
Longmont, 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 Longmont, CO
Longmont, CO has no months that meet our "pleasant" threshold — every season has tradeoffs.