Weather on August 20
San Marcos, CA
55 Years of Data
Avg High
86°F
Avg Low
64°F
Warmest
1992
85°F avg
Coldest
2002
68°F avg
About This Date
August 20th in San Marcos, CA typically brings warm summer weather, with average highs around 86°F and lows near 64°F. Over 55 years of records, the warmest August 20th was in 1992 (85°F average), while the coldest was 2002 (68°F) — a 17°F range across recorded history. Rain or other precipitation has occurred on about 2% of August 20th dates historically, with the wettest August 20th recording 3.48" of rain. The last decade has been 3.1°F warmer on this date compared to 20-30 years ago.
The last decade has been 3.1°F warmer on this date compared to 20-30 years ago.
Planning for August 20th in San Marcos, 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 | 95° | 63° | 79° | — | — |
| 2024 | 99° | 66° | 82° | — | — |
| 2023 | 77° | 71° | 74° | 3.48" | — |
| 2022 | 89° | 66° | 78° | — | — |
| 2021 | 81° | 67° | 74° | — | — |
| 2020 | 99° | 72° | 85° | — | — |
| 2019 | 89° | 63° | 76° | — | — |
| 2018 | 89° | 69° | 79° | — | — |
| 2017 | 85° | 64° | 74° | — | — |
| 2016 | 83° | 64° | 73° | — | — |
| 2015 | 85° | 66° | 75° | — | — |
| 2014 | 81° | 66° | 73° | — | — |
| 2013 | 87° | 62° | 75° | — | — |
| 2012 | 92° | 70° | 81° | — | — |
| 2011 | 82° | 62° | 72° | — | — |
| 2010 | 78° | 66° | 72° | — | — |
| 2009 | 72° | 65° | 68° | — | — |
| 2008 | 74° | 64° | 69° | — | — |
| 2007 | 97° | 67° | 82° | — | — |
| 2006 | 73° | 65° | 69° | — | — |
| 2005 | 73° | 63° | 68° | — | — |
| 2004 | 85° | 65° | 75° | — | — |
| 2003 | 90° | 64° | 77° | — | — |
| 2002coldest | 71° | 64° | 68° | — | — |
| 2001 | 91° | 64° | 78° | — | — |
| 2000 | 89° | 59° | 74° | — | — |
| 1999 | 90° | 61° | 75° | — | — |
| 1998 | 88° | 59° | 73° | — | — |
| 1997 | 91° | 71° | 81° | — | — |
| 1996 | 89° | 59° | 74° | — | — |
| 1995 | 86° | 64° | 75° | — | — |
| 1994 | 90° | 66° | 78° | — | — |
| 1993 | 87° | 58° | 72° | — | — |
| 1992warmest | 101° | 70° | 85° | — | — |
| 1991 | 85° | 59° | 72° | — | — |
| 1990 | 80° | 61° | 70° | — | — |
| 1989 | 80° | 62° | 71° | — | — |
| 1988 | 79° | 62° | 70° | — | — |
| 1987 | 84° | 61° | 72° | — | — |
| 1986 | 96° | 72° | 84° | — | — |
| 1985 | 83° | 58° | 70° | — | — |
| 1984 | 85° | 69° | 77° | — | — |
| 1983 | 82° | 62° | 72° | — | — |
| 1982 | 95° | 62° | 79° | — | — |
| 1981 | 92° | 61° | 76° | — | — |
| 1980 | 83° | 60° | 71° | — | — |
| 1979 | 78° | 62° | 70° | — | — |
| 1978 | 88° | 55° | 71° | — | — |
| 1977 | 92° | 65° | 78° | — | — |
| 1976 | 82° | 63° | 72° | — | — |
| 1975 | 80° | 60° | 70° | — | — |
| 1974 | 82° | 61° | 71° | — | — |
| 1973 | 93° | 68° | 81° | — | — |
| 1972 | 88° | 55° | 71° | — | — |
| 1971 | 85° | 62° | 73° | — | — |
55 years of data from ESCONDIDO #2