Weather on August 23
Rancho Cucamonga, CA
55 Years of Data
Avg High
93°F
Avg Low
62°F
Warmest
1998
87°F avg
Coldest
1978
67°F avg
About This Date
August 23rd in Rancho Cucamonga, CA typically brings hot summer weather, with average highs around 93°F and lows near 62°F — a 31°F daily swing. Over 42 years of records, the warmest August 23rd was in 1998 (87°F average), while the coldest was 1978 (67°F) — a 20°F range across recorded history. This date has historically been dry, with little recorded precipitation. The last decade has been 1.7°F warmer on this date compared to 20-30 years ago.
The last decade has been 1.7°F warmer on this date compared to 20-30 years ago.
Planning for August 23rd in Rancho Cucamonga, CA? Stay hydrated and seek shade during peak afternoon hours.
Warming Trend
1.3°F per decade on this date
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 102° | 72° | 87° | — | — |
| 2024 | 86° | 61° | 73° | — | — |
| 2023 | 95° | 63° | 79° | — | — |
| 2022 | 96° | 66° | 81° | — | — |
| 2021 | 87° | 63° | 75° | — | — |
| 2020 | 98° | 73° | 86° | — | — |
| 2019 | 91° | 61° | 76° | — | — |
| 2018 | 93° | 66° | 80° | — | — |
| 2017 | 87° | 64° | 76° | — | — |
| 2016 | 92° | 64° | 78° | — | — |
| 2015 | 96° | 64° | 80° | — | — |
| 2014 | 90° | 63° | 76° | — | — |
| 2013 | 100° | 68° | 84° | — | — |
| 2012 | 90° | 67° | 78° | — | — |
| 2011 | 97° | 66° | 81° | — | — |
| 2010 | 103° | 67° | 85° | — | — |
| 2009 | 93° | 64° | 79° | — | — |
| 2008 | 93° | 63° | 78° | — | — |
| 2007 | 90° | 64° | 77° | — | — |
| 2006 | 100° | 62° | 81° | — | — |
| 2005 | 91° | 60° | 76° | — | — |
| 2004 | 81° | 58° | 69° | — | — |
| 2003 | 95° | 61° | 78° | — | — |
| 2002 | 89° | 60° | 75° | — | — |
| 2001 | 87° | 59° | 73° | — | — |
| 2000 | 95° | 62° | 79° | — | — |
| 1999 | 101° | 63° | 82° | — | — |
| 1998warmest | 105° | 68° | 87° | — | — |
| 1984 | 102° | 61° | 81° | — | — |
| 1983 | 85° | 54° | 69° | — | — |
| 1982 | 94° | 67° | 80° | — | — |
| 1981 | 95° | 60° | 78° | — | — |
| 1980 | 90° | 60° | 75° | — | — |
| 1979 | 95° | 60° | 78° | — | — |
| 1978coldest | 86° | 49° | 67° | — | — |
| 1977 | 85° | 62° | 73° | — | — |
| 1976 | 91° | 54° | 72° | — | — |
| 1975 | 95° | 56° | 75° | — | — |
| 1974 | 95° | 55° | 75° | — | — |
| 1973 | 88° | 54° | 71° | — | — |
| 1972 | 95° | 57° | 76° | — | — |
| 1971 | 88° | 55° | 71° | — | — |
42 years of data from ONTARIO INTL AP