Weather on August 21
Saint Louis, MO
55 Years of Data
Avg High
86°F
Avg Low
65°F
Warmest
2003
88°F avg
Coldest
2004
63°F avg
About This Date
August 21st in Saint Louis, MO typically brings warm summer weather, with average highs around 86°F and lows near 65°F. Over 52 years of records, the warmest August 21st was in 2003 (88°F average), while the coldest was 2004 (63°F) — a 25°F range across recorded history. Rain or other precipitation has occurred on about 23% of August 21st dates historically, with the wettest August 21st recording 3.56" 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 Saint Louis, MO? Stay hydrated and seek shade during peak afternoon hours.
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 81° | 66° | 73° | — | — |
| 2024 | 77° | 54° | 65° | — | — |
| 2023 | 96° | 77° | 87° | — | — |
| 2022 | 83° | 65° | 74° | — | — |
| 2021 | 88° | 73° | 80° | — | — |
| 2020 | 85° | 56° | 70° | — | — |
| 2019 | 89° | 69° | 79° | 1.88" | — |
| 2018 | 77° | 69° | 73° | 1.04" | — |
| 2017 | 90° | 74° | 82° | — | — |
| 2016 | 83° | 62° | 72° | — | — |
| 2015 | 82° | 62° | 72° | — | — |
| 2014 | 90° | 74° | 82° | 0.25" | — |
| 2013 | 89° | 69° | 79° | — | — |
| 2012 | 86° | 62° | 74° | — | — |
| 2011 | 89° | 69° | 79° | 0.36" | — |
| 2010 | 94° | 69° | 81° | 3.56" | — |
| 2009 | 80° | 63° | 71° | 0.05" | — |
| 2008 | 82° | 68° | 75° | 0.48" | — |
| 2007 | 83° | 75° | 79° | 0.25" | — |
| 2006 | 84° | 66° | 75° | — | — |
| 2005 | 92° | 72° | 82° | — | — |
| 2004coldest | 70° | 57° | 63° | 0.08" | — |
| 2003warmest | 98° | 78° | 88° | — | — |
| 2002 | 86° | 71° | 79° | — | — |
| 2001 | 83° | 64° | 73° | — | — |
| 2000 | 75° | 64° | 70° | — | — |
| 1999 | 80° | 57° | 69° | — | — |
| 1998 | 85° | 62° | 73° | — | — |
| 1997 | 78° | 59° | 69° | — | — |
| 1996 | 90° | 70° | 80° | — | — |
| 1995 | 86° | 72° | 79° | — | — |
| 1994 | 78° | 60° | 69° | — | — |
| 1993 | 85° | 67° | 76° | — | — |
| 1992 | 82° | 57° | 70° | — | — |
| 1991 | 88° | 66° | 77° | — | — |
| 1990 | 91° | 69° | 80° | — | — |
| 1989 | 82° | 70° | 76° | — | — |
| 1988 | 92° | 69° | 80° | — | — |
| 1987 | 100° | 60° | 80° | 0.84" | — |
| 1986 | 88° | 62° | 75° | — | — |
| 1985 | 81° | 61° | 71° | — | — |
| 1981 | 80° | 61° | 70° | — | — |
| 1980 | 90° | — | — | — | — |
| 1979 | 95° | 67° | 81° | — | — |
| 1978 | 85° | 50° | 67° | — | — |
| 1977 | 85° | 65° | 75° | 0.76" | — |
| 1976 | 88° | 60° | 74° | — | — |
| 1975 | 91° | 67° | 79° | — | — |
| 1974 | 91° | 62° | 77° | — | — |
| 1973 | 90° | 57° | 73° | — | — |
| 1972 | 100° | 72° | 86° | 0.03" | — |
| 1971 | 90° | 67° | 78° | — | — |
52 years of data from ST LOUIS ST LOUIS UNIV