Weather on December 15
Rancho Cucamonga, CA
55 Years of Data
Avg High
67°F
Avg Low
42°F
Warmest
1980
68°F avg
Coldest
1971
43°F avg
About This Date
December 15th in Rancho Cucamonga, CA typically brings mild winter weather, with average highs around 67°F and lows near 42°F — a 25°F daily swing. Over 41 years of records, the warmest December 15th was in 1980 (68°F average), while the coldest was 1971 (43°F) — a 25°F range across recorded history. Rain or other precipitation has occurred on about 10% of December 15th dates historically, with the wettest December 15th recording 4.32" of rain. The last decade has been 1.6°F warmer on this date compared to 20-30 years ago.
The last decade has been 1.6°F warmer on this date compared to 20-30 years ago.
Planning for December 15th in Rancho Cucamonga, CA? Great weather for outdoor activities.
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 78° | 49° | 63° | — | — |
| 2024 | 66° | 45° | 55° | — | — |
| 2023 | 79° | 44° | 61° | — | — |
| 2022 | 60° | 40° | 50° | — | — |
| 2021 | 53° | 36° | 44° | — | — |
| 2020 | 69° | 42° | 56° | — | — |
| 2019 | 62° | 46° | 54° | — | — |
| 2018 | 74° | 46° | 60° | — | — |
| 2017 | 81° | 48° | 64° | — | — |
| 2016 | 67° | 51° | 59° | 0.76" | — |
| 2015 | 58° | 32° | 45° | — | — |
| 2014 | 64° | 46° | 55° | — | — |
| 2013 | 81° | 42° | 61° | — | — |
| 2012 | 57° | 43° | 50° | 0.08" | — |
| 2011 | 55° | 39° | 47° | 1.12" | — |
| 2010 | 55° | 50° | 53° | — | — |
| 2009 | 69° | 41° | 55° | — | — |
| 2008 | 51° | 43° | 47° | 4.32" | — |
| 2007 | 68° | 37° | 53° | — | — |
| 2006 | 71° | 47° | 59° | — | — |
| 2005 | 64° | 43° | 53° | — | — |
| 2004 | 77° | 45° | 61° | — | — |
| 2003 | 68° | 41° | 55° | — | — |
| 2002 | 64° | 50° | 57° | — | — |
| 2001 | 57° | 33° | 45° | — | — |
| 2000 | 60° | 44° | 52° | — | — |
| 1999 | 72° | 43° | 57° | — | — |
| 1998 | 79° | 41° | 60° | — | — |
| 1983 | 68° | 40° | 54° | — | — |
| 1982 | 69° | 35° | 52° | — | — |
| 1981 | 74° | 42° | 58° | — | — |
| 1980warmest | 83° | 53° | 68° | — | — |
| 1979 | 74° | 42° | 58° | — | — |
| 1978 | 68° | 42° | 55° | — | — |
| 1977 | 65° | 46° | 55° | — | — |
| 1976 | 77° | 46° | 62° | — | — |
| 1975 | 66° | 31° | 48° | — | — |
| 1974 | 70° | 40° | 55° | — | — |
| 1973 | 72° | 39° | 55° | — | — |
| 1972 | 62° | 31° | 46° | — | — |
| 1971coldest | 54° | 33° | 43° | — | — |
41 years of data from ONTARIO INTL AP