Weather on August 21
San Ramon, CA
55 Years of Data
Avg High
84°F
Avg Low
57°F
Warmest
2004
99°F avg
Coldest
2011
59°F avg
About This Date
August 21st in San Ramon, CA typically brings warm summer weather, with average highs around 84°F and lows near 57°F — a 27°F daily swing. Over 55 years of records, the warmest August 21st was in 2004 (99°F average), while the coldest was 2011 (59°F) — a 40°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 Ramon, CA? Stay hydrated and seek shade during peak afternoon hours.
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 90° | 60° | 75° | — | — |
| 2024 | 86° | 53° | 70° | — | — |
| 2023 | 85° | 60° | 72° | — | — |
| 2022 | 91° | 69° | 80° | — | — |
| 2021 | 77° | 52° | 64° | — | — |
| 2020 | 85° | 62° | 73° | — | — |
| 2019 | 74° | 56° | 65° | — | — |
| 2018 | 77° | 49° | 63° | — | — |
| 2017 | 80° | 60° | 70° | — | — |
| 2016 | 83° | 67° | 75° | — | — |
| 2015 | 77° | 54° | 65° | — | — |
| 2014 | 76° | 56° | 66° | — | — |
| 2013 | 85° | 63° | 74° | — | — |
| 2012 | 86° | 67° | 76° | — | — |
| 2011coldest | 70° | 48° | 59° | — | — |
| 2010 | 81° | 53° | 67° | — | — |
| 2009 | 86° | 68° | 77° | — | — |
| 2008 | 80° | 54° | 67° | — | — |
| 2007 | 87° | 60° | 74° | — | — |
| 2006 | 82° | 52° | 67° | — | — |
| 2005 | 81° | 53° | 67° | — | — |
| 2004warmest | 138° | 59° | 99° | — | — |
| 2003 | 74° | 59° | 66° | — | — |
| 2002 | 83° | 52° | 67° | — | — |
| 2001 | 74° | 52° | 63° | — | — |
| 2000 | 88° | 53° | 70° | — | — |
| 1999 | 94° | 54° | 74° | — | — |
| 1998 | 74° | 49° | 61° | — | — |
| 1997 | 88° | 58° | 73° | — | — |
| 1996 | 91° | 54° | 72° | — | — |
| 1995 | 86° | 58° | 72° | — | — |
| 1994 | 76° | 54° | 65° | — | — |
| 1993 | 91° | 56° | 73° | — | — |
| 1992 | 95° | 63° | 79° | — | — |
| 1991 | 81° | 54° | 67° | — | — |
| 1990 | 83° | 59° | 71° | — | — |
| 1989 | 75° | 53° | 64° | — | — |
| 1988 | 84° | 59° | 72° | — | — |
| 1987 | 73° | 50° | 62° | — | — |
| 1986 | 89° | 65° | 77° | — | — |
| 1985 | 80° | 53° | 67° | — | — |
| 1984 | 83° | 60° | 71° | — | — |
| 1983 | 72° | 53° | 62° | — | — |
| 1982 | 89° | 70° | 79° | — | — |
| 1981 | 78° | 54° | 66° | — | — |
| 1980 | 79° | 49° | 64° | — | — |
| 1979 | 70° | 52° | 61° | — | — |
| 1978 | 85° | 55° | 70° | — | — |
| 1977 | 88° | 63° | 75° | — | — |
| 1976 | 86° | 58° | 72° | — | — |
| 1975 | 85° | 64° | 74° | — | — |
| 1974 | 90° | 50° | 70° | — | — |
| 1973 | 92° | 61° | 76° | — | — |
| 1972 | 85° | 57° | 71° | — | — |
| 1971 | 86° | 55° | 71° | — | — |
55 years of data from LIVERMORE CALIFORNIA