Weather on September 4
San Marcos, CA
55 Years of Data
Avg High
88°F
Avg Low
64°F
Warmest
2022
90°F avg
Coldest
1973
66°F avg
About This Date
September 4th in San Marcos, CA typically brings warm fall weather, with average highs around 88°F and lows near 64°F. Over 55 years of records, the warmest September 4th was in 2022 (90°F average), while the coldest was 1973 (66°F) — a 24°F range across recorded history. Rain or other precipitation has occurred on about 2% of September 4th dates historically. The last decade has been 4.5°F warmer on this date compared to 20-30 years ago.
The last decade has been 4.5°F warmer on this date compared to 20-30 years ago.
Planning for September 4th 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 | 94° | 67° | 80° | — | — |
| 2024 | 96° | 68° | 82° | — | — |
| 2023 | 80° | 62° | 71° | — | — |
| 2022warmest | 102° | 77° | 90° | — | — |
| 2021 | 95° | 61° | 78° | — | — |
| 2020 | 97° | 65° | 81° | — | — |
| 2019 | 96° | 73° | 85° | 0.2" | — |
| 2018 | 75° | 67° | 71° | — | — |
| 2017 | 77° | 71° | 74° | — | — |
| 2016 | 80° | 62° | 71° | — | — |
| 2015 | 81° | 65° | 73° | — | — |
| 2014 | 86° | 67° | 76° | — | — |
| 2013 | 99° | 73° | 86° | — | — |
| 2012 | 99° | 67° | 83° | — | — |
| 2011 | 89° | 61° | 75° | — | — |
| 2010 | 97° | 63° | 80° | — | — |
| 2009 | 83° | 69° | 76° | — | — |
| 2008 | 78° | 67° | 72° | — | — |
| 2007 | 85° | 69° | 77° | — | — |
| 2006 | 79° | 67° | 73° | — | — |
| 2005 | 73° | 60° | 67° | — | — |
| 2004 | 79° | 58° | 68° | — | — |
| 2003 | 92° | 64° | 78° | — | — |
| 2002 | 95° | 66° | 81° | — | — |
| 2001 | 88° | 65° | 76° | — | — |
| 2000 | 84° | 54° | 69° | — | — |
| 1999 | 77° | 57° | 67° | — | — |
| 1998 | 75° | 69° | 72° | — | — |
| 1997 | 101° | 72° | 86° | — | — |
| 1996 | 84° | 64° | 74° | — | — |
| 1995 | 96° | 67° | 81° | — | — |
| 1994 | 88° | 61° | 74° | — | — |
| 1993 | 95° | 65° | 80° | — | — |
| 1992 | 88° | 62° | 75° | — | — |
| 1991 | 82° | 63° | 72° | — | — |
| 1990 | 91° | 65° | 78° | — | — |
| 1989 | 90° | 59° | 74° | — | — |
| 1988 | 103° | 74° | 88° | — | — |
| 1987 | 86° | 64° | 75° | — | — |
| 1986 | 84° | 61° | 72° | — | — |
| 1985 | 70° | 62° | 66° | — | — |
| 1984 | 99° | 69° | 84° | — | — |
| 1983 | 90° | 65° | 77° | — | — |
| 1982 | 101° | 68° | 84° | — | — |
| 1981 | 84° | 62° | 73° | — | — |
| 1980 | 82° | 60° | 71° | — | — |
| 1979 | 93° | 55° | 74° | — | — |
| 1978 | 97° | 68° | 82° | — | — |
| 1977 | 90° | 62° | 76° | — | — |
| 1976 | 91° | 63° | 77° | — | — |
| 1975 | 93° | 60° | 77° | — | — |
| 1974 | 94° | 63° | 78° | — | — |
| 1973coldest | 72° | 61° | 66° | — | — |
| 1972 | 94° | 67° | 80° | — | — |
| 1971 | 82° | 51° | 67° | — | — |
55 years of data from ESCONDIDO #2