Weather on August 21
Vallejo, CA
55 Years of Data
Avg High
84°F
Avg Low
56°F
Warmest
1998
81°F avg
Coldest
2012
61°F avg
About This Date
August 21st in Vallejo, CA typically brings warm summer weather, with average highs around 84°F and lows near 56°F — a 28°F daily swing. Over 55 years of records, the warmest August 21st was in 1998 (81°F average), while the coldest was 2012 (61°F) — a 20°F range across recorded history. This date has historically been dry, with little recorded precipitation. The last decade has been 1.9°F warmer on this date compared to 20-30 years ago.
The last decade has been 1.9°F warmer on this date compared to 20-30 years ago.
Planning for August 21st in Vallejo, CA? Stay hydrated and seek shade during peak afternoon hours.
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 98° | 60° | 79° | — | — |
| 2024 | 84° | 59° | 72° | — | — |
| 2023 | 94° | 59° | 76° | — | — |
| 2022 | 90° | 57° | 73° | — | — |
| 2021 | 72° | 59° | 65° | — | — |
| 2020 | 94° | 59° | 76° | — | — |
| 2019 | 92° | 58° | 75° | — | — |
| 2018 | 77° | 55° | 66° | — | — |
| 2017 | 77° | 60° | 69° | — | — |
| 2016 | 80° | 56° | 68° | — | — |
| 2015 | 82° | 59° | 71° | — | — |
| 2014 | 81° | 59° | 70° | — | — |
| 2013 | 77° | 55° | 66° | — | — |
| 2012coldest | 72° | 51° | 61° | — | — |
| 2011 | 71° | 56° | 63° | — | — |
| 2010 | 71° | 53° | 62° | — | — |
| 2009 | 90° | 52° | 71° | — | — |
| 2008 | 82° | 61° | 71° | — | — |
| 2007 | 89° | 59° | 74° | — | — |
| 2006 | 81° | 55° | 68° | — | — |
| 2005 | 75° | 55° | 65° | — | — |
| 2004 | 77° | 55° | 66° | — | — |
| 2003 | 76° | 56° | 66° | — | — |
| 2002 | 80° | 53° | 67° | — | — |
| 2001 | 75° | 62° | 69° | — | — |
| 2000 | 82° | 53° | 68° | — | — |
| 1999 | 89° | 55° | 72° | — | — |
| 1998warmest | 82° | 81° | 81° | — | — |
| 1997 | 86° | 57° | 72° | — | — |
| 1996 | 90° | 58° | 74° | — | — |
| 1995 | 87° | 55° | 71° | — | — |
| 1994 | 85° | 52° | 68° | — | — |
| 1993 | 94° | 54° | 74° | — | — |
| 1992 | 86° | 56° | 71° | — | — |
| 1991 | 84° | 53° | 69° | — | — |
| 1990 | 86° | 59° | 73° | — | — |
| 1989 | 76° | 55° | 65° | — | — |
| 1988 | 79° | 50° | 64° | — | — |
| 1987 | 82° | 47° | 64° | — | — |
| 1986 | 89° | 50° | 70° | — | — |
| 1985 | 85° | 56° | 70° | — | — |
| 1984 | 84° | 56° | 70° | — | — |
| 1983 | 83° | 55° | 69° | — | — |
| 1982 | 98° | 63° | 80° | — | — |
| 1981 | 92° | 59° | 75° | — | — |
| 1980 | 87° | 53° | 70° | — | — |
| 1979 | 82° | 58° | 70° | — | — |
| 1978 | 82° | 51° | 67° | — | — |
| 1977 | 92° | 51° | 71° | — | — |
| 1976 | 84° | — | — | — | — |
| 1975 | 87° | 54° | 70° | — | — |
| 1974 | 90° | 54° | 72° | — | — |
| 1973 | 79° | 48° | 63° | — | — |
| 1972 | 89° | 62° | 76° | — | — |
| 1971 | 82° | 59° | 71° | — | — |
55 years of data from VALLEJO