Weather on August 18
Fairfield, CA
55 Years of Data
Avg High
89°F
Avg Low
56°F
Warmest
2020
88°F avg
Coldest
1985
60°F avg
About This Date
August 18th in Fairfield, CA typically brings warm summer weather, with average highs around 89°F and lows near 56°F — a 33°F daily swing. Over 55 years of records, the warmest August 18th was in 2020 (88°F average), while the coldest was 1985 (60°F) — a 28°F range across recorded history. Rain or other precipitation has occurred on about 4% of August 18th dates historically. The last decade has been 3.1°F warmer on this date compared to 20-30 years ago.
The last decade has been 3.1°F warmer on this date compared to 20-30 years ago.
Planning for August 18th in Fairfield, CA? Stay hydrated and seek shade during peak afternoon hours.
Warming Trend
1.2°F per decade on this date
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 86° | 54° | 70° | — | — |
| 2024 | 85° | 60° | 72° | — | — |
| 2023 | 96° | 62° | 79° | — | — |
| 2022 | 97° | 67° | 82° | — | — |
| 2021 | 82° | 56° | 69° | — | — |
| 2020warmest | 105° | 72° | 88° | — | — |
| 2019 | 80° | 58° | 69° | — | — |
| 2018 | 97° | 56° | 76° | — | — |
| 2017 | 89° | 58° | 73° | — | — |
| 2016 | 93° | 57° | 75° | — | — |
| 2015 | 99° | 59° | 79° | — | — |
| 2014 | 84° | 58° | 71° | — | — |
| 2013 | 99° | 58° | 78° | — | — |
| 2012 | 94° | 64° | 79° | — | — |
| 2011 | 89° | 55° | 72° | — | — |
| 2010 | 91° | 53° | 72° | — | — |
| 2009 | 91° | 56° | 73° | — | — |
| 2008 | 79° | 57° | 68° | — | — |
| 2007 | 90° | 58° | 74° | — | — |
| 2006 | 90° | 54° | 72° | — | — |
| 2005 | 87° | 54° | 70° | — | — |
| 2004 | 97° | 59° | 78° | — | — |
| 2003 | 93° | 60° | 77° | — | — |
| 2002 | 84° | 54° | 69° | — | — |
| 2001 | 94° | 58° | 76° | — | — |
| 2000 | 90° | 57° | 73° | — | — |
| 1999 | 90° | 55° | 72° | — | — |
| 1998 | 80° | 57° | 69° | — | — |
| 1997 | 78° | 58° | 68° | — | — |
| 1996 | 84° | 55° | 70° | — | — |
| 1995 | 93° | 58° | 75° | — | — |
| 1994 | 95° | 59° | 77° | — | — |
| 1993 | 89° | 53° | 71° | — | — |
| 1992 | 100° | 56° | 78° | — | — |
| 1991 | 81° | 55° | 68° | — | — |
| 1990 | 79° | 62° | 70° | — | — |
| 1989 | 83° | 54° | 68° | — | — |
| 1988 | 98° | 60° | 79° | — | — |
| 1987 | 76° | 55° | 65° | — | — |
| 1986 | 89° | 48° | 69° | — | — |
| 1985coldest | 76° | 44° | 60° | — | — |
| 1984 | 105° | 46° | 76° | — | — |
| 1983 | — | 56° | — | — | — |
| 1982 | 100° | 58° | 79° | — | — |
| 1981 | 90° | 55° | 72° | — | — |
| 1980 | 87° | 52° | 69° | — | — |
| 1979 | 91° | 56° | 73° | — | — |
| 1978 | 84° | 51° | 68° | — | — |
| 1977 | 82° | 55° | 69° | — | — |
| 1976 | 76° | 57° | 66° | 0.2" | — |
| 1975 | 77° | 57° | 67° | 0.36" | — |
| 1974 | 84° | 57° | 71° | — | — |
| 1973 | 85° | 53° | 69° | — | — |
| 1972 | 89° | 57° | 73° | — | — |
| 1971 | 91° | 52° | 71° | — | — |
55 years of data from FAIRFIELD