Weather on August 21
Des Moines, IA
55 Years of Data
Avg High
83°F
Avg Low
61°F
Warmest
2003
88°F avg
Coldest
1991
63°F avg
About This Date
August 21st in Des Moines, IA typically brings warm summer weather, with average highs around 83°F and lows near 61°F. Over 55 years of records, the warmest August 21st was in 2003 (88°F average), while the coldest was 1991 (63°F) — a 25°F range across recorded history. Rain or other precipitation has occurred on about 33% of August 21st dates historically, with the wettest August 21st recording 3.61" of rain. The last decade has been 1.1°F warmer on this date compared to 20-30 years ago.
The last decade has been 1.1°F warmer on this date compared to 20-30 years ago.
Planning for August 21st in Des Moines, IA? Stay hydrated and seek shade during peak afternoon hours. Consider bringing rain gear or an umbrella.
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 82° | 67° | 74° | — | — |
| 2024 | 77° | 63° | 70° | 0.13" | — |
| 2023 | 92° | 76° | 84° | — | — |
| 2022 | 77° | 62° | 70° | — | — |
| 2021 | 80° | 63° | 71° | — | — |
| 2020 | 85° | 62° | 73° | — | — |
| 2019 | 89° | 64° | 77° | 0.05" | — |
| 2018 | 75° | 61° | 68° | — | — |
| 2017 | 87° | 60° | 74° | 3.61" | — |
| 2016 | 72° | 54° | 63° | 0.03" | — |
| 2015 | 78° | 55° | 67° | — | — |
| 2014 | 82° | 66° | 74° | 0.41" | — |
| 2013 | 90° | 71° | 80° | — | — |
| 2012 | 85° | 57° | 71° | — | — |
| 2011 | 85° | 64° | 74° | — | — |
| 2010 | 82° | 68° | 75° | 0.94" | — |
| 2009 | 75° | 60° | 68° | 0.18" | — |
| 2008 | 85° | 61° | 73° | 0.08" | — |
| 2007 | 86° | 69° | 78° | 1.98" | — |
| 2006 | 82° | 59° | 71° | — | — |
| 2005 | 90° | 63° | 76° | — | — |
| 2004 | 76° | 51° | 63° | — | — |
| 2003warmest | 100° | 75° | 88° | — | — |
| 2002 | 78° | 52° | 65° | — | — |
| 2001 | 83° | 54° | 68° | — | — |
| 2000 | 76° | 62° | 69° | — | — |
| 1999 | 81° | 51° | 66° | — | — |
| 1998 | 93° | 68° | 81° | 3.58" | — |
| 1997 | 76° | 52° | 64° | — | — |
| 1996 | 85° | 62° | 73° | — | — |
| 1995 | 82° | 54° | 68° | — | — |
| 1994 | 76° | 52° | 64° | — | — |
| 1993 | 78° | 58° | 68° | — | — |
| 1992 | 77° | 52° | 64° | — | — |
| 1991coldest | 74° | 52° | 63° | 0.18" | — |
| 1990 | 77° | 64° | 71° | 0.05" | — |
| 1989 | 85° | 61° | 73° | — | — |
| 1988 | 91° | 63° | 77° | — | — |
| 1987 | 92° | 68° | 80° | — | — |
| 1986 | 79° | 64° | 71° | — | — |
| 1985 | 78° | 58° | 68° | — | — |
| 1984 | 78° | 65° | 71° | 0.08" | — |
| 1983 | 96° | 73° | 85° | 0.1" | — |
| 1982 | 83° | 58° | 70° | — | — |
| 1981 | 81° | 53° | 67° | — | — |
| 1980 | 82° | 59° | 71° | — | — |
| 1979 | 80° | 62° | 71° | 1.17" | — |
| 1978 | 74° | 58° | 66° | 0.71" | — |
| 1977 | 78° | 60° | 69° | 2.9" | — |
| 1976 | 87° | 62° | 75° | — | — |
| 1975 | 90° | 70° | 80° | — | — |
| 1974 | 89° | 68° | 79° | — | — |
| 1973 | 83° | 63° | 73° | — | — |
| 1972 | 93° | 69° | 81° | 0.97" | — |
| 1971 | 87° | 62° | 75° | — | — |
55 years of data from ANKENY