Weather on August 21
Denver, CO
55 Years of Data
Avg High
88°F
Avg Low
56°F
Warmest
2019
81°F avg
Coldest
1974
64°F avg
About This Date
August 21st in Denver, CO typically brings warm summer weather, with average highs around 88°F and lows near 56°F — a 32°F daily swing. Over 55 years of records, the warmest August 21st was in 2019 (81°F average), while the coldest was 1974 (64°F) — a 17°F range across recorded history. Rain or other precipitation has occurred on about 27% of August 21st dates historically, with the wettest August 21st recording 2.34" of rain. Temperatures on this date have remained relatively stable over the past several decades.
Temperatures on this date have remained relatively stable over the past several decades.
Planning for August 21st in Denver, CO? Stay hydrated and seek shade during peak afternoon hours.
Warming Trend
0.8°F per decade on this date
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 99° | 57° | 78° | — | — |
| 2024 | 98° | 63° | 80° | — | — |
| 2023 | 96° | 60° | 78° | — | — |
| 2022 | 83° | 55° | 69° | 0.1" | — |
| 2021 | 82° | 50° | 66° | — | — |
| 2020 | 94° | 60° | 77° | — | — |
| 2019warmest | 99° | 63° | 81° | — | — |
| 2018 | 79° | 52° | 65° | — | — |
| 2017 | 91° | 58° | 74° | — | — |
| 2016 | 77° | 50° | 64° | — | — |
| 2015 | 89° | 52° | 70° | — | — |
| 2014 | 93° | 58° | 75° | 0.1" | — |
| 2013 | 98° | 63° | 80° | — | — |
| 2012 | 81° | 53° | 67° | — | — |
| 2011 | 88° | 58° | 73° | — | — |
| 2010 | 88° | 58° | 73° | — | — |
| 2009 | 84° | 50° | 67° | — | — |
| 2008 | 92° | 54° | 73° | — | — |
| 2007 | 99° | 58° | 78° | — | — |
| 2006 | 89° | 56° | 72° | — | — |
| 2005 | 92° | 59° | 75° | 0.18" | — |
| 2004 | 80° | 48° | 64° | 0.08" | — |
| 2003 | 100° | 58° | 79° | — | — |
| 2002 | 92° | 62° | 77° | 0.23" | — |
| 2001 | 92° | 61° | 76° | — | — |
| 2000 | 76° | 56° | 66° | — | — |
| 1999 | 86° | 56° | 71° | — | — |
| 1998 | 87° | 59° | 73° | — | — |
| 1997 | 94° | 60° | 77° | — | — |
| 1996 | 86° | 55° | 71° | 0.08" | — |
| 1995 | 89° | 57° | 73° | 0.51" | — |
| 1994 | 87° | 55° | 71° | — | — |
| 1993 | 82° | 54° | 68° | 0.13" | — |
| 1992 | 85° | 55° | 70° | — | — |
| 1991 | 89° | 52° | 70° | — | — |
| 1990 | 90° | 55° | 72° | — | — |
| 1989 | 88° | 51° | 69° | — | — |
| 1988 | 92° | 53° | 72° | 0.05" | — |
| 1987 | 86° | 58° | 72° | 0.53" | — |
| 1986 | 84° | 53° | 69° | — | — |
| 1985 | 91° | 58° | 74° | 0.05" | — |
| 1984 | 72° | 58° | 65° | 2.34" | — |
| 1983 | 88° | 58° | 73° | 1.14" | — |
| 1982 | 84° | 57° | 71° | 0.03" | — |
| 1981 | 94° | 50° | 72° | — | — |
| 1980 | 85° | 45° | 65° | — | — |
| 1979 | 80° | 50° | 65° | — | — |
| 1978 | 91° | 52° | 71° | — | — |
| 1977 | 84° | 53° | 69° | — | — |
| 1976 | 91° | 53° | 72° | — | — |
| 1975 | 84° | 54° | 69° | — | — |
| 1974coldest | 85° | 44° | 64° | — | — |
| 1973 | 90° | 62° | 76° | 0.13" | — |
| 1972 | 84° | 56° | 70° | — | — |
| 1971 | 94° | 58° | 76° | — | — |
55 years of data from NORTHGLENN