Weather on August 21
Santa Rosa, CA
55 Years of Data
Avg High
81°F
Avg Low
53°F
Warmest
2019
76°F avg
Coldest
2010
59°F avg
About This Date
August 21st in Santa Rosa, CA typically brings warm summer weather, with average highs around 81°F and lows near 53°F — a 28°F daily swing. Over 55 years of records, the warmest August 21st was in 2019 (76°F average), while the coldest was 2010 (59°F) — a 17°F range across recorded history. Rain or other precipitation has occurred on about 4% of August 21st dates historically. The last decade has been 2.3°F warmer on this date compared to 20-30 years ago.
The last decade has been 2.3°F warmer on this date compared to 20-30 years ago.
Planning for August 21st in Santa Rosa, CA? Stay hydrated and seek shade during peak afternoon hours.
Warming Trend
0.6°F per decade on this date
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 99° | 54° | 76° | — | — |
| 2024 | 90° | 48° | 69° | — | — |
| 2023 | 85° | 60° | 72° | — | — |
| 2022 | 92° | 55° | 73° | — | — |
| 2021 | 71° | 55° | 63° | 0.08" | — |
| 2020 | 95° | 56° | 75° | — | — |
| 2019warmest | 97° | 55° | 76° | — | — |
| 2018 | 79° | 54° | 66° | — | — |
| 2017 | 66° | 58° | 62° | — | — |
| 2016 | 75° | 53° | 64° | — | — |
| 2015 | 75° | 55° | 65° | — | — |
| 2014 | 79° | 55° | 67° | — | — |
| 2013 | 74° | 53° | 63° | — | — |
| 2012 | 80° | 50° | 65° | — | — |
| 2011 | 77° | 55° | 66° | — | — |
| 2010coldest | 67° | 51° | 59° | — | — |
| 2009 | 93° | 53° | 73° | — | — |
| 2008 | 87° | 60° | 74° | — | — |
| 2007 | 91° | 56° | 73° | — | — |
| 2006 | 75° | 52° | 63° | — | — |
| 2005 | 76° | 52° | 64° | — | — |
| 2004 | 77° | 56° | 66° | — | — |
| 2003 | 81° | 57° | 69° | — | — |
| 2002 | 77° | 53° | 65° | — | — |
| 2001 | 82° | 50° | 66° | — | — |
| 2000 | 83° | 54° | 68° | — | — |
| 1999 | 88° | 55° | 71° | — | — |
| 1998 | 81° | 52° | 66° | — | — |
| 1997 | 83° | 55° | 69° | — | — |
| 1996 | 85° | 54° | 69° | — | — |
| 1995 | 79° | 56° | 67° | — | — |
| 1994 | 83° | 53° | 68° | — | — |
| 1993 | 87° | 56° | 71° | — | — |
| 1992 | 85° | 51° | 68° | — | — |
| 1991 | 75° | 53° | 64° | — | — |
| 1990 | 79° | 57° | 68° | — | — |
| 1989 | 69° | 55° | 62° | 0.08" | — |
| 1988 | 74° | 55° | 64° | — | — |
| 1987 | 69° | 51° | 60° | — | — |
| 1986 | 73° | 48° | 61° | — | — |
| 1985 | 73° | 49° | 61° | — | — |
| 1984 | 71° | 51° | 61° | — | — |
| 1983 | 79° | 57° | 68° | — | — |
| 1982 | 94° | 50° | 72° | — | — |
| 1981 | 81° | 49° | 65° | — | — |
| 1980 | 74° | 50° | 62° | — | — |
| 1979 | 73° | 58° | 65° | — | — |
| 1978 | 90° | 50° | 70° | — | — |
| 1977 | 92° | 50° | 71° | — | — |
| 1976 | 81° | 50° | 65° | — | — |
| 1975 | 79° | 50° | 64° | — | — |
| 1974 | 96° | 50° | 73° | — | — |
| 1973 | 80° | 47° | 63° | — | — |
| 1972 | 93° | 51° | 72° | — | — |
| 1971 | 85° | 52° | 68° | — | — |
55 years of data from SANTA ROSA