Weather on August 21
San Leandro, CA
55 Years of Data
Avg High
74°F
Avg Low
55°F
Warmest
2025
76°F avg
Coldest
2010
55°F avg
About This Date
August 21st in San Leandro, CA typically brings pleasant summer weather, with average highs around 74°F and lows near 55°F. Over 52 years of records, the warmest August 21st was in 2025 (76°F average), while the coldest was 2010 (55°F) — a 21°F range across recorded history. This date has historically been dry, with little recorded precipitation. 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 San Leandro, CA? Great weather for outdoor activities.
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025warmest | 91° | 60° | 76° | — | — |
| 2024 | 75° | 55° | 65° | — | — |
| 2023 | 72° | 58° | 65° | — | — |
| 2022 | 75° | 54° | 64° | — | — |
| 2021 | 66° | 53° | 60° | — | — |
| 2020 | 84° | 57° | 71° | — | — |
| 2019 | 83° | 55° | 69° | — | — |
| 2018 | 61° | 52° | 56° | — | — |
| 2017 | 69° | 56° | 62° | — | — |
| 2016 | 69° | 53° | 61° | — | — |
| 2015 | 67° | 56° | 61° | — | — |
| 2014 | 75° | 56° | 65° | — | — |
| 2013 | 69° | 53° | 61° | — | — |
| 2012 | 70° | 51° | 60° | — | — |
| 2011 | 65° | 52° | 58° | — | — |
| 2010coldest | 60° | 50° | 55° | — | — |
| 2009 | 83° | 58° | 70° | — | — |
| 2008 | 72° | 61° | 66° | — | — |
| 2007 | 85° | 55° | 70° | — | — |
| 2006 | 69° | 55° | 62° | — | — |
| 2005 | 68° | 52° | 60° | — | — |
| 2004 | 69° | 56° | 62° | — | — |
| 2003 | 74° | 58° | 66° | — | — |
| 2002 | 72° | 51° | 61° | — | — |
| 2001 | 67° | 51° | 59° | — | — |
| 2000 | 77° | 52° | 64° | — | — |
| 1999 | 86° | 54° | 70° | — | — |
| 1998 | 77° | 54° | 65° | — | — |
| 1997 | 81° | 55° | 68° | — | — |
| 1996 | 81° | 53° | 67° | — | — |
| 1995 | 71° | 54° | 62° | — | — |
| 1994 | 66° | 53° | 60° | — | — |
| 1993 | 82° | 57° | 70° | — | — |
| 1989 | 73° | 56° | 64° | — | — |
| 1988 | 70° | 57° | 63° | — | — |
| 1987 | 73° | 54° | 63° | — | — |
| 1986 | 74° | 53° | 63° | — | — |
| 1985 | 71° | 56° | 63° | — | — |
| 1984 | 75° | 56° | 65° | — | — |
| 1983 | 75° | 58° | 66° | — | — |
| 1982 | 76° | 53° | 64° | — | — |
| 1981 | 75° | 56° | 65° | — | — |
| 1980 | 75° | 54° | 64° | — | — |
| 1979 | 75° | 58° | 66° | — | — |
| 1978 | 76° | 53° | 64° | — | — |
| 1977 | 68° | 55° | 62° | — | — |
| 1976 | 82° | 59° | 71° | — | — |
| 1975 | 78° | 50° | 64° | — | — |
| 1974 | 85° | 51° | 68° | — | — |
| 1973 | 79° | 46° | 62° | — | — |
| 1972 | 77° | 57° | 67° | — | — |
| 1971 | 71° | 54° | 62° | — | — |
52 years of data from UPPER SAN LEANDRO FILTERS