Weather on September 17
Antioch, CA
55 Years of Data
Avg High
82°F
Avg Low
57°F
Warmest
2025
83°F avg
Coldest
1977
59°F avg
About This Date
September 17th in Antioch, CA typically brings warm fall weather, with average highs around 82°F and lows near 57°F — a 25°F daily swing. Over 55 years of records, the warmest September 17th was in 2025 (83°F average), while the coldest was 1977 (59°F) — a 24°F range across recorded history. Rain or other precipitation has occurred on about 5% of September 17th dates historically, with the wettest September 17th recording 1.07" of rain. The last decade has been 4.2°F cooler on this date compared to 20-30 years ago.
The last decade has been 4.2°F cooler on this date compared to 20-30 years ago.
Planning for September 17th in Antioch, CA? Stay hydrated and seek shade during peak afternoon hours.
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025warmest | 93° | 74° | 83° | — | — |
| 2024 | 68° | 50° | 59° | — | — |
| 2023 | 67° | 54° | 60° | — | — |
| 2022 | 68° | 55° | 62° | — | — |
| 2021 | 73° | 50° | 62° | — | — |
| 2020 | 87° | 60° | 74° | — | — |
| 2019 | 80° | 59° | 70° | — | — |
| 2018 | 71° | 55° | 63° | — | — |
| 2017 | 75° | 62° | 69° | — | — |
| 2016 | 94° | 55° | 74° | — | — |
| 2015 | 79° | 58° | 68° | — | — |
| 2014 | 86° | 61° | 73° | — | — |
| 2013 | 80° | 59° | 70° | — | — |
| 2012 | 83° | 56° | 69° | — | — |
| 2011 | 95° | 55° | 75° | — | — |
| 2010 | 80° | 59° | 70° | — | — |
| 2009 | 93° | 65° | 79° | — | — |
| 2008 | 74° | 54° | 64° | — | — |
| 2007 | 81° | 56° | 68° | — | — |
| 2006 | 88° | 55° | 71° | — | — |
| 2005 | 78° | 54° | 66° | — | — |
| 2004 | 88° | 60° | 74° | — | — |
| 2003 | 83° | 60° | 71° | — | — |
| 2002 | 87° | 66° | 77° | — | — |
| 2001 | 83° | 54° | 68° | — | — |
| 2000 | 92° | 64° | 78° | — | — |
| 1999 | 82° | 54° | 68° | — | — |
| 1998 | 83° | 70° | 76° | — | — |
| 1997 | 83° | 58° | 70° | — | — |
| 1996 | 80° | 61° | 70° | — | — |
| 1995 | 83° | 55° | 69° | — | — |
| 1994 | 95° | 60° | 78° | — | — |
| 1993 | 71° | 51° | 61° | — | — |
| 1992 | 84° | 56° | 70° | — | — |
| 1991 | 94° | 58° | 76° | — | — |
| 1990 | 86° | 56° | 71° | — | — |
| 1989 | 66° | 56° | 61° | 1.07" | — |
| 1988 | 86° | 54° | 70° | — | — |
| 1987 | 88° | 58° | 73° | — | — |
| 1986 | 76° | 54° | 65° | — | — |
| 1985 | 83° | 51° | 67° | — | — |
| 1984 | 97° | 64° | 80° | — | — |
| 1983 | 85° | 57° | 71° | — | — |
| 1982 | 70° | 57° | 63° | 0.03" | — |
| 1981 | 85° | 54° | 69° | — | — |
| 1980 | 81° | 60° | 70° | — | — |
| 1979 | 102° | 54° | 78° | — | — |
| 1978 | 89° | 58° | 73° | — | — |
| 1977coldest | 62° | 56° | 59° | 0.33" | — |
| 1976 | 78° | 57° | 68° | — | — |
| 1975 | 87° | 58° | 72° | — | — |
| 1974 | 81° | 56° | 68° | — | — |
| 1973 | 77° | 51° | 64° | — | — |
| 1972 | 74° | 54° | 64° | — | — |
| 1971 | 88° | 60° | 74° | — | — |
55 years of data from ANTIOCH FIBREBRD MILLS