Weather on August 21
San Bernardino, CA
55 Years of Data
Avg High
94°F
Avg Low
63°F
Warmest
1982
94°F avg
Coldest
1989
71°F avg
About This Date
August 21st in San Bernardino, CA typically brings hot summer weather, with average highs around 94°F and lows near 63°F — a 31°F daily swing. Over 48 years of records, the warmest August 21st was in 1982 (94°F average), while the coldest was 1989 (71°F) — a 23°F range across recorded history. This date has historically been dry, with little recorded precipitation.
Planning for August 21st in San Bernardino, CA? Stay hydrated and seek shade during peak afternoon hours.
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 106° | 70° | 88° | — | — |
| 2017 | 87° | 58° | 72° | — | — |
| 2016 | 88° | 68° | 78° | — | — |
| 2015 | 85° | 62° | 73° | — | — |
| 2014 | 88° | 61° | 74° | — | — |
| 2013 | 98° | 65° | 81° | — | — |
| 2012 | 96° | 69° | 83° | — | — |
| 2011 | 92° | 56° | 74° | — | — |
| 2010 | 99° | 63° | 81° | — | — |
| 2009 | 99° | 62° | 80° | — | — |
| 2008 | 92° | 61° | 76° | — | — |
| 2007 | 102° | 61° | 81° | — | — |
| 2006 | 95° | 63° | 79° | — | — |
| 2005 | 99° | 61° | 80° | — | — |
| 2004 | 91° | 62° | 77° | — | — |
| 2003 | 94° | 68° | 81° | — | — |
| 2002 | 82° | 68° | 75° | — | — |
| 2001 | 86° | 59° | 73° | — | — |
| 2000 | 95° | 59° | 77° | — | — |
| 1999 | 102° | 63° | 82° | — | — |
| 1998 | 100° | 59° | 80° | — | — |
| 1997 | 99° | 66° | 82° | — | — |
| 1996 | 98° | 62° | 80° | — | — |
| 1995 | 96° | 71° | 84° | — | — |
| 1994 | 94° | 64° | 79° | — | — |
| 1993 | 93° | 58° | 75° | — | — |
| 1992 | 100° | 68° | 84° | — | — |
| 1991 | 100° | 60° | 80° | — | — |
| 1990 | 87° | 57° | 72° | — | — |
| 1989coldest | 82° | 60° | 71° | — | — |
| 1988 | 88° | 60° | 74° | — | — |
| 1987 | 92° | 60° | 76° | — | — |
| 1986 | 100° | 71° | 86° | — | — |
| 1985 | 95° | 55° | 75° | — | — |
| 1984 | 94° | 71° | 82° | — | — |
| 1983 | 83° | 64° | 73° | — | — |
| 1982warmest | 109° | 78° | 94° | — | — |
| 1981 | 107° | 63° | 85° | — | — |
| 1980 | 95° | 58° | 76° | — | — |
| 1979 | 90° | 63° | 76° | — | — |
| 1978 | 95° | 60° | 78° | — | — |
| 1977 | 94° | 67° | 80° | — | — |
| 1976 | 94° | 59° | 76° | — | — |
| 1975 | 86° | 57° | 72° | — | — |
| 1974 | 98° | 58° | 78° | — | — |
| 1973 | 96° | 68° | 82° | — | — |
| 1972 | 101° | 59° | 80° | — | — |
| 1971 | 93° | 62° | 78° | — | — |
48 years of data from NORTON AFB