Weather on August 18
Sunnyvale, CA
55 Years of Data
Avg High
77°F
Avg Low
59°F
Warmest
2020
83°F avg
Coldest
1975
60°F avg
About This Date
August 18th in Sunnyvale, CA typically brings pleasant summer weather, with average highs around 77°F and lows near 59°F. Over 55 years of records, the warmest August 18th was in 2020 (83°F average), while the coldest was 1975 (60°F) — a 23°F range across recorded history. Rain or other precipitation has occurred on about 5% of August 18th dates historically, with the wettest August 18th recording 1.35" of rain. The last decade has been 5.4°F warmer on this date compared to 20-30 years ago.
The last decade has been 5.4°F warmer on this date compared to 20-30 years ago.
Planning for August 18th in Sunnyvale, CA? Great weather for outdoor activities.
Warming Trend
0.7°F per decade on this date
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 75° | 57° | 66° | — | — |
| 2024 | 80° | 64° | 72° | — | — |
| 2023 | 86° | 64° | 75° | — | — |
| 2022 | 84° | 61° | 72° | — | — |
| 2021 | 78° | 59° | 69° | — | — |
| 2020warmest | 97° | 70° | 83° | — | — |
| 2019 | 83° | 59° | 71° | — | — |
| 2018 | 81° | 58° | 69° | — | — |
| 2017 | 77° | 62° | 70° | — | — |
| 2016 | 77° | 62° | 70° | — | — |
| 2015 | 78° | 60° | 69° | — | — |
| 2014 | 72° | 62° | 67° | — | — |
| 2013 | 85° | 59° | 72° | — | — |
| 2012 | 77° | 59° | 68° | — | — |
| 2011 | 70° | 59° | 64° | — | — |
| 2010 | 70° | 58° | 64° | — | — |
| 2009 | 75° | 60° | 68° | — | — |
| 2008 | 73° | 59° | 66° | — | — |
| 2007 | 78° | 56° | 67° | — | — |
| 2006 | 74° | 58° | 66° | — | — |
| 2005 | 72° | 57° | 64° | — | — |
| 2004 | 82° | 59° | 71° | — | — |
| 2003 | 78° | 60° | 69° | — | — |
| 2002 | 73° | 59° | 66° | — | — |
| 2001 | 75° | 56° | 65° | — | — |
| 2000 | 78° | 55° | 67° | — | — |
| 1999 | 70° | 58° | 64° | — | — |
| 1998 | 71° | 56° | 63° | — | — |
| 1997 | 78° | 61° | 69° | — | — |
| 1996 | 77° | 54° | 65° | — | — |
| 1995 | 87° | 54° | 70° | — | — |
| 1994 | 83° | 57° | 70° | — | — |
| 1993 | 77° | 61° | 69° | — | — |
| 1992 | 83° | 60° | 71° | — | — |
| 1991 | 71° | 61° | 66° | — | — |
| 1990 | 77° | 64° | 71° | — | — |
| 1989 | 73° | 61° | 67° | — | — |
| 1988 | 83° | 58° | 70° | — | — |
| 1987 | 75° | 61° | 68° | — | — |
| 1986 | 78° | 57° | 68° | — | — |
| 1985 | 76° | 53° | 64° | — | — |
| 1984 | 82° | 63° | 72° | — | — |
| 1983 | 73° | 63° | 68° | 0.1" | — |
| 1982 | 71° | 60° | 66° | — | — |
| 1981 | 69° | 58° | 63° | — | — |
| 1980 | 76° | 56° | 66° | — | — |
| 1979 | 77° | 61° | 69° | — | — |
| 1978 | 90° | 59° | 74° | — | — |
| 1977 | 73° | 60° | 67° | — | — |
| 1976 | 71° | 61° | 66° | 0.58" | — |
| 1975coldest | 63° | 58° | 60° | 1.35" | — |
| 1974 | 79° | 57° | 68° | — | — |
| 1973 | 73° | 57° | 65° | — | — |
| 1972 | 72° | 57° | 64° | — | — |
| 1971 | 80° | 62° | 71° | — | — |
55 years of data from MOFFETT FED AIRFIELD