Weather on September 1
Costa Mesa, CA
55 Years of Data
Avg High
83°F
Avg Low
66°F
Warmest
1998
86°F avg
Coldest
1973
69°F avg
About This Date
September 1st in Costa Mesa, CA typically brings warm fall weather, with average highs around 83°F and lows near 66°F. Over 55 years of records, the warmest September 1st was in 1998 (86°F average), while the coldest was 1973 (69°F) — a 17°F range across recorded history. This date has historically been dry, with little recorded precipitation. The last decade has been 1.0°F warmer on this date compared to 20-30 years ago.
The last decade has been 1.0°F warmer on this date compared to 20-30 years ago.
Planning for September 1st in Costa Mesa, CA? Stay hydrated and seek shade during peak afternoon hours.
Warming Trend
0.4°F per decade on this date
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 85° | 68° | 76° | — | — |
| 2024 | 79° | 68° | 73° | — | — |
| 2023 | 81° | 69° | 75° | — | — |
| 2022 | 88° | 72° | 80° | — | — |
| 2021 | 76° | 69° | 72° | — | — |
| 2020 | 78° | 67° | 72° | — | — |
| 2019 | 80° | 71° | 76° | — | — |
| 2018 | 77° | 68° | 73° | — | — |
| 2017 | 96° | 72° | 84° | — | — |
| 2016 | 77° | 66° | 72° | — | — |
| 2015 | 78° | 69° | 74° | — | — |
| 2014 | 82° | 71° | 77° | — | — |
| 2013 | 90° | 74° | 82° | — | — |
| 2012 | 87° | 66° | 77° | — | — |
| 2011 | 76° | 63° | 69° | — | — |
| 2010 | 80° | 62° | 71° | — | — |
| 2009 | 86° | 71° | 79° | — | — |
| 2008 | 78° | 67° | 72° | — | — |
| 2007 | 88° | 72° | 80° | — | — |
| 2006 | 88° | 65° | 76° | — | — |
| 2005 | 78° | 63° | 70° | — | — |
| 2004 | 83° | 62° | 72° | — | — |
| 2003 | 76° | 65° | 70° | — | — |
| 2002 | 95° | 66° | 81° | — | — |
| 2001 | 80° | 65° | 72° | — | — |
| 2000 | 76° | 64° | 70° | — | — |
| 1999 | 75° | 62° | 69° | — | — |
| 1998warmest | 97° | 75° | 86° | — | — |
| 1997 | 89° | 63° | 76° | — | — |
| 1996 | 87° | 67° | 77° | — | — |
| 1995 | 91° | 65° | 78° | — | — |
| 1994 | 80° | 65° | 72° | — | — |
| 1993 | 84° | 66° | 75° | — | — |
| 1992 | 79° | 64° | 71° | — | — |
| 1991 | 85° | 62° | 73° | — | — |
| 1990 | 81° | 62° | 71° | — | — |
| 1989 | 83° | 61° | 72° | — | — |
| 1988 | 80° | 62° | 71° | — | — |
| 1987 | 98° | 65° | 81° | — | — |
| 1986 | 81° | 64° | 72° | — | — |
| 1985 | 87° | 69° | 78° | — | — |
| 1984 | 85° | 67° | 76° | — | — |
| 1983 | 87° | 66° | 77° | — | — |
| 1982 | 97° | 64° | 80° | — | — |
| 1981 | 82° | 64° | 73° | — | — |
| 1980 | 79° | 63° | 71° | — | — |
| 1979 | 81° | 66° | 73° | — | — |
| 1978 | 83° | 66° | 74° | — | — |
| 1977 | 80° | 64° | 72° | — | — |
| 1976 | 89° | 67° | 78° | — | — |
| 1975 | 79° | 60° | 69° | — | — |
| 1974 | 88° | 60° | 74° | — | — |
| 1973coldest | 78° | 60° | 69° | — | — |
| 1972 | 85° | 67° | 76° | — | — |
| 1971 | 82° | 62° | 72° | — | — |
55 years of data from SANTA ANA JOHN WAYNE AP