Weather on August 21
Philadelphia, PA
55 Years of Data
Avg High
84°F
Avg Low
67°F
Warmest
2005
88°F avg
Coldest
2007
60°F avg
About This Date
August 21st in Philadelphia, PA typically brings warm summer weather, with average highs around 84°F and lows near 67°F. Over 55 years of records, the warmest August 21st was in 2005 (88°F average), while the coldest was 2007 (60°F) — a 28°F range across recorded history. Rain or other precipitation has occurred on about 16% of August 21st dates historically, with the wettest August 21st recording 4.85" 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 Philadelphia, PA? Stay hydrated and seek shade during peak afternoon hours.
Warming Trend
0.9°F per decade on this date
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 72° | 61° | 66° | — | — |
| 2024 | 74° | 57° | 65° | — | — |
| 2023 | 88° | 68° | 78° | — | — |
| 2022 | 94° | 73° | 83° | — | — |
| 2021 | 85° | 73° | 79° | 0.15" | — |
| 2020 | 85° | 69° | 77° | — | — |
| 2019 | 91° | 77° | 84° | — | — |
| 2018 | 77° | 69° | 73° | — | — |
| 2017 | 86° | 68° | 77° | — | — |
| 2016 | 92° | 74° | 83° | — | — |
| 2015 | 91° | 72° | 81° | 0.25" | — |
| 2014 | 89° | 71° | 80° | — | — |
| 2013 | 88° | 72° | 80° | — | — |
| 2012 | 83° | 67° | 75° | — | — |
| 2011 | 88° | 69° | 78° | 1.68" | — |
| 2010 | 92° | 72° | 82° | — | — |
| 2009 | 93° | 72° | 82° | 3.35" | — |
| 2008 | 86° | 68° | 77° | — | — |
| 2007coldest | 63° | 58° | 60° | 2.13" | — |
| 2006 | 87° | 69° | 78° | — | — |
| 2005warmest | 98° | 79° | 88° | — | — |
| 2004 | 84° | 66° | 75° | — | — |
| 2003 | 92° | 75° | 83° | — | — |
| 2002 | 91° | 71° | 81° | — | — |
| 2001 | 85° | 70° | 77° | — | — |
| 2000 | 79° | 56° | 67° | — | — |
| 1999 | 71° | 61° | 66° | — | — |
| 1998 | 90° | 66° | 78° | — | — |
| 1997 | 82° | 66° | 74° | 0.03" | — |
| 1996 | 81° | 68° | 74° | — | — |
| 1995 | 86° | 63° | 74° | — | — |
| 1994 | 86° | 71° | 79° | — | — |
| 1993 | 83° | 62° | 72° | 4.85" | — |
| 1992 | 80° | 62° | 71° | — | — |
| 1991 | 82° | 68° | 75° | — | — |
| 1990 | 67° | 62° | 64° | — | — |
| 1989 | 84° | 74° | 79° | — | — |
| 1988 | 83° | 62° | 72° | — | — |
| 1987 | 86° | 67° | 76° | — | — |
| 1986 | 68° | 64° | 66° | — | — |
| 1985 | 76° | 65° | 70° | — | — |
| 1984 | 82° | 62° | 72° | — | — |
| 1983 | 90° | 71° | 80° | — | — |
| 1982 | 76° | 63° | 69° | — | — |
| 1981 | 83° | 63° | 73° | — | — |
| 1980 | 79° | 66° | 72° | — | — |
| 1979 | 77° | 61° | 69° | — | — |
| 1978 | 84° | 63° | 73° | — | — |
| 1977 | 79° | 59° | 69° | 0.69" | — |
| 1976 | 90° | 67° | 78° | — | — |
| 1975 | 81° | 68° | 74° | — | — |
| 1974 | 86° | 70° | 78° | — | — |
| 1973 | 77° | 66° | 72° | 0.03" | — |
| 1972 | 86° | 66° | 76° | — | — |
| 1971 | 91° | 74° | 82° | — | — |
55 years of data from PHILADELPHIA WSFO