Weather on August 15
San Marcos, CA
55 Years of Data
Avg High
87°F
Avg Low
65°F
Warmest
1992
87°F avg
Coldest
2010
64°F avg
About This Date
August 15th in San Marcos, CA typically brings warm summer weather, with average highs around 87°F and lows near 65°F. Over 55 years of records, the warmest August 15th was in 1992 (87°F average), while the coldest was 2010 (64°F) — a 23°F range across recorded history. This date has historically been dry, with little recorded precipitation. The last decade has been 2.0°F warmer on this date compared to 20-30 years ago.
The last decade has been 2.0°F warmer on this date compared to 20-30 years ago.
Planning for August 15th in San Marcos, CA? Stay hydrated and seek shade during peak afternoon hours.
Warming Trend
1.1°F per decade on this date
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 85° | 64° | 74° | — | — |
| 2024 | 94° | 64° | 79° | — | — |
| 2023 | 92° | 66° | 79° | — | — |
| 2022 | 94° | 68° | 81° | — | — |
| 2021 | 91° | 68° | 80° | — | — |
| 2020 | 100° | 74° | 87° | — | — |
| 2019 | 95° | 62° | 79° | — | — |
| 2018 | 88° | 69° | 78° | — | — |
| 2017 | 78° | 64° | 71° | — | — |
| 2016 | 101° | 70° | 85° | — | — |
| 2015 | 101° | 71° | 86° | — | — |
| 2014 | 93° | 67° | 80° | — | — |
| 2013 | 91° | 62° | 77° | — | — |
| 2012 | 90° | 67° | 78° | — | — |
| 2011 | 84° | 63° | 73° | — | — |
| 2010coldest | 69° | 59° | 64° | — | — |
| 2009 | 73° | 64° | 69° | — | — |
| 2008 | 76° | 69° | 72° | — | — |
| 2007 | 80° | 69° | 75° | — | — |
| 2006 | 74° | 66° | 70° | — | — |
| 2005 | 72° | 65° | 68° | — | — |
| 2004 | 87° | 63° | 75° | — | — |
| 2003 | 99° | 73° | 86° | — | — |
| 2002 | 87° | 62° | 75° | — | — |
| 2001 | 94° | 66° | 80° | — | — |
| 2000 | 97° | 67° | 82° | — | — |
| 1999 | 84° | 57° | 71° | — | — |
| 1998 | 89° | 65° | 77° | — | — |
| 1997 | 81° | 65° | 73° | — | — |
| 1996 | 98° | 73° | 86° | — | — |
| 1995 | 88° | 65° | 76° | — | — |
| 1994 | 102° | 70° | 86° | — | — |
| 1993 | 81° | 62° | 71° | — | — |
| 1992warmest | 100° | 73° | 87° | — | — |
| 1991 | 82° | 65° | 73° | — | — |
| 1990 | 77° | 65° | 71° | — | — |
| 1989 | 87° | 64° | 76° | — | — |
| 1988 | 84° | 55° | 70° | — | — |
| 1987 | 78° | 61° | 69° | — | — |
| 1986 | 84° | 63° | 73° | — | — |
| 1985 | 88° | 58° | 73° | — | — |
| 1984 | 90° | 68° | 79° | — | — |
| 1983 | 90° | 69° | 79° | — | — |
| 1982 | 81° | 61° | 71° | — | — |
| 1981 | 90° | 65° | 77° | — | — |
| 1980 | 84° | 66° | 75° | — | — |
| 1979 | 85° | 60° | 72° | — | — |
| 1978 | 88° | 58° | 73° | — | — |
| 1977 | 95° | 62° | 79° | — | — |
| 1976 | 77° | 58° | 67° | — | — |
| 1975 | 83° | 59° | 71° | — | — |
| 1974 | 82° | 58° | 70° | — | — |
| 1973 | 86° | 62° | 74° | — | — |
| 1972 | 84° | 62° | 73° | — | — |
| 1971 | 87° | 64° | 76° | — | — |
55 years of data from ESCONDIDO #2