Weather on September 15
Antioch, CA
55 Years of Data
Avg High
84°F
Avg Low
57°F
Warmest
1971
92°F avg
Coldest
2018
60°F avg
About This Date
September 15th in Antioch, CA typically brings warm fall weather, with average highs around 84°F and lows near 57°F — a 27°F daily swing. Over 55 years of records, the warmest September 15th was in 1971 (92°F average), while the coldest was 2018 (60°F) — a 32°F range across recorded history. This date has historically been dry, with little recorded precipitation. The last decade has been 4.7°F cooler on this date compared to 20-30 years ago.
The last decade has been 4.7°F cooler on this date compared to 20-30 years ago.
Planning for September 15th in Antioch, CA? Stay hydrated and seek shade during peak afternoon hours.
Cooling Trend
0.6°F per decade on this date
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 87° | 67° | 77° | — | — |
| 2024 | 68° | 51° | 60° | — | — |
| 2023 | 77° | 55° | 66° | — | — |
| 2022 | 66° | 55° | 61° | — | — |
| 2021 | 77° | 50° | 64° | — | — |
| 2020 | 86° | 59° | 73° | — | — |
| 2019 | 89° | 55° | 72° | — | — |
| 2018coldest | 66° | 53° | 60° | — | — |
| 2017 | 74° | 55° | 64° | — | — |
| 2016 | 84° | 56° | 70° | — | — |
| 2015 | 96° | 67° | 81° | — | — |
| 2014 | 87° | 65° | 76° | — | — |
| 2013 | 84° | 57° | 71° | — | — |
| 2012 | 87° | 56° | 71° | — | — |
| 2011 | 87° | 58° | 72° | — | — |
| 2010 | 89° | 55° | 72° | — | — |
| 2009 | 84° | 59° | 72° | — | — |
| 2008 | 86° | 56° | 71° | — | — |
| 2007 | 77° | 56° | 66° | — | — |
| 2006 | 73° | 55° | 64° | — | — |
| 2005 | 75° | 52° | 63° | — | — |
| 2004 | 94° | 61° | 77° | — | — |
| 2003 | 87° | 56° | 71° | — | — |
| 2002 | 88° | 55° | 71° | — | — |
| 2001 | 89° | 57° | 73° | — | — |
| 2000 | 83° | 64° | 73° | — | — |
| 1999 | 84° | 56° | 70° | — | — |
| 1998 | 93° | 60° | 77° | — | — |
| 1997 | 81° | 55° | 68° | — | — |
| 1996 | 81° | 61° | 71° | — | — |
| 1995 | 86° | 54° | 70° | — | — |
| 1994 | 86° | 57° | 72° | — | — |
| 1993 | 77° | 53° | 65° | — | — |
| 1992 | 84° | 51° | 68° | — | — |
| 1991 | 83° | 53° | 68° | — | — |
| 1990 | 81° | 60° | 70° | — | — |
| 1989 | 96° | 60° | 78° | — | — |
| 1988 | 86° | 53° | 70° | — | — |
| 1987 | 78° | — | — | — | — |
| 1986 | 74° | 49° | 61° | — | — |
| 1985 | 85° | 54° | 69° | — | — |
| 1984 | 95° | 56° | 75° | — | — |
| 1983 | 100° | 59° | 80° | — | — |
| 1982 | 81° | 57° | 69° | — | — |
| 1981 | 86° | 54° | 70° | — | — |
| 1980 | 71° | 53° | 62° | — | — |
| 1979 | 100° | 60° | 80° | — | — |
| 1978 | 86° | 59° | 73° | — | — |
| 1977 | 74° | 52° | 63° | — | — |
| 1976 | 98° | 53° | 76° | — | — |
| 1975 | 81° | 52° | 66° | — | — |
| 1974 | 78° | 57° | 68° | — | — |
| 1973 | 79° | 50° | 64° | — | — |
| 1972 | 80° | 53° | 67° | — | — |
| 1971warmest | 106° | 78° | 92° | — | — |
55 years of data from ANTIOCH FIBREBRD MILLS