Weather on May 15
Rancho Cucamonga, CA
55 Years of Data
Avg High
78°F
Avg Low
54°F
Warmest
2014
84°F avg
Coldest
1974
55°F avg
About This Date
May 15th in Rancho Cucamonga, CA typically brings pleasant spring weather, with average highs around 78°F and lows near 54°F. Over 41 years of records, the warmest May 15th was in 2014 (84°F average), while the coldest was 1974 (55°F) — a 29°F range across recorded history. Rain or other precipitation has occurred on about 17% of May 15th dates historically. Temperatures on this date have remained relatively stable over the past several decades.
Temperatures on this date have remained relatively stable over the past several decades.
Planning for May 15th in Rancho Cucamonga, CA? Great weather for outdoor activities.
Warming Trend
1.1°F per decade on this date
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 81° | 54° | 67° | — | — |
| 2024 | 69° | 57° | 63° | — | — |
| 2023 | 83° | 58° | 70° | — | — |
| 2022 | 89° | 58° | 73° | — | — |
| 2021 | 72° | 59° | 65° | — | — |
| 2020 | 83° | 58° | 70° | — | — |
| 2019 | 75° | 62° | 69° | — | — |
| 2018 | 77° | 52° | 64° | — | — |
| 2017 | 63° | 51° | 57° | 0.38" | — |
| 2016 | 67° | 59° | 63° | — | — |
| 2015 | 66° | 51° | 59° | 0.08" | — |
| 2014warmest | 102° | 66° | 84° | — | — |
| 2013 | 82° | 56° | 69° | — | — |
| 2012 | 83° | 53° | 68° | — | — |
| 2011 | 64° | 49° | 56° | 0.36" | — |
| 2010 | 85° | 53° | 69° | — | — |
| 2009 | 88° | 57° | 72° | — | — |
| 2008 | 100° | 61° | 80° | — | — |
| 2007 | 76° | 55° | 65° | — | — |
| 2006 | 84° | 58° | 71° | — | — |
| 2005 | 89° | 59° | 74° | — | — |
| 2004 | 88° | 57° | 72° | — | — |
| 2003 | 75° | 52° | 63° | — | — |
| 2002 | 76° | 56° | 66° | — | — |
| 2001 | 79° | 54° | 66° | — | — |
| 2000 | 77° | 52° | 64° | 0.05" | — |
| 1999 | 70° | 53° | 61° | — | — |
| 1984 | 76° | 50° | 63° | — | — |
| 1983 | 76° | 46° | 61° | — | — |
| 1982 | 78° | 46° | 62° | — | — |
| 1981 | 65° | 54° | 59° | 0.3" | — |
| 1980 | 66° | 48° | 57° | — | — |
| 1979 | 86° | 48° | 67° | — | — |
| 1978 | 80° | 50° | 65° | — | — |
| 1977 | 64° | 51° | 58° | 0.08" | — |
| 1976 | 82° | 53° | 68° | — | — |
| 1975 | 72° | 51° | 61° | — | — |
| 1974coldest | 58° | 52° | 55° | 0.05" | — |
| 1973 | 79° | 51° | 65° | — | — |
| 1972 | 88° | 59° | 73° | — | — |
| 1971 | 76° | 50° | 63° | — | — |
41 years of data from ONTARIO INTL AP