Weather on September 20
Antioch, CA
55 Years of Data
Avg High
84°F
Avg Low
57°F
Warmest
2015
82°F avg
Coldest
2017
58°F avg
About This Date
September 20th 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 20th was in 2015 (82°F average), while the coldest was 2017 (58°F) — a 24°F range across recorded history. Rain or other precipitation has occurred on about 2% of September 20th dates historically. The last decade has been 2.2°F cooler on this date compared to 20-30 years ago.
The last decade has been 2.2°F cooler on this date compared to 20-30 years ago.
Planning for September 20th in Antioch, CA? Stay hydrated and seek shade during peak afternoon hours.
Warming Trend
0.3°F per decade on this date
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 81° | 62° | 71° | — | — |
| 2024 | 77° | 60° | 69° | — | — |
| 2023 | 70° | 55° | 62° | — | — |
| 2022 | 69° | 54° | 61° | — | — |
| 2021 | 84° | 62° | 73° | — | — |
| 2020 | 90° | 60° | 75° | — | — |
| 2019 | 84° | 61° | 72° | — | — |
| 2018 | 87° | 68° | 78° | — | — |
| 2017coldest | 65° | 51° | 58° | — | — |
| 2016 | 85° | 61° | 73° | — | — |
| 2015warmest | 99° | 66° | 82° | — | — |
| 2014 | 85° | 61° | 73° | — | — |
| 2013 | 78° | 58° | 68° | — | — |
| 2012 | 86° | 53° | 70° | — | — |
| 2011 | 100° | 62° | 81° | — | — |
| 2010 | 80° | 55° | 68° | — | — |
| 2009 | 90° | 67° | 78° | — | — |
| 2008 | 78° | 55° | 67° | — | — |
| 2007 | 71° | 51° | 61° | — | — |
| 2006 | 85° | 63° | 74° | — | — |
| 2005 | 78° | 52° | 65° | — | — |
| 2004 | 71° | 48° | 60° | — | — |
| 2003 | 90° | 60° | 75° | — | — |
| 2002 | 94° | 63° | 78° | — | — |
| 2001 | 85° | 54° | 69° | — | — |
| 2000 | 98° | 64° | 81° | — | — |
| 1999 | 78° | 55° | 67° | — | — |
| 1998 | 83° | 61° | 72° | — | — |
| 1997 | 85° | 66° | 75° | — | — |
| 1996 | 87° | 58° | 72° | — | — |
| 1995 | 98° | 65° | 81° | — | — |
| 1994 | 88° | 57° | 72° | — | — |
| 1993 | 82° | 49° | 65° | — | — |
| 1992 | 93° | 57° | 75° | — | — |
| 1991 | 85° | 54° | 69° | — | — |
| 1990 | 90° | 62° | 76° | — | — |
| 1989 | 76° | 53° | 64° | — | — |
| 1988 | 86° | 58° | 72° | — | — |
| 1987 | 88° | 55° | 71° | — | — |
| 1986 | 70° | 50° | 60° | — | — |
| 1985 | 85° | 52° | 68° | — | — |
| 1984 | 95° | 61° | 78° | — | — |
| 1983 | 90° | 67° | 78° | — | — |
| 1982 | 76° | 51° | 63° | — | — |
| 1981 | 89° | 54° | 71° | — | — |
| 1980 | 80° | 48° | 64° | — | — |
| 1979 | 88° | 52° | 70° | — | — |
| 1978 | 79° | 46° | 62° | — | — |
| 1977 | 73° | 52° | 62° | 0.18" | — |
| 1976 | 80° | 54° | 67° | — | — |
| 1975 | 83° | 52° | 67° | — | — |
| 1974 | 86° | 57° | 72° | — | — |
| 1973 | 82° | 64° | 73° | — | — |
| 1972 | 76° | 56° | 66° | — | — |
| 1971 | 89° | 60° | 75° | — | — |
55 years of data from ANTIOCH FIBREBRD MILLS