Weather on December 11
Ontario, CA
55 Years of Data
Avg High
67°F
Avg Low
43°F
Warmest
2025
68°F avg
Coldest
1972
38°F avg
About This Date
December 11th in Ontario, CA typically brings mild winter weather, with average highs around 67°F and lows near 43°F. Over 41 years of records, the warmest December 11th was in 2025 (68°F average), while the coldest was 1972 (38°F) — a 30°F range across recorded history. Rain or other precipitation has occurred on about 10% of December 11th dates historically, with the wettest December 11th recording 2.72" of rain. The last decade has been 3.3°F warmer on this date compared to 20-30 years ago.
The last decade has been 3.3°F warmer on this date compared to 20-30 years ago.
Planning for December 11th in Ontario, CA? Great weather for outdoor activities.
Warming Trend
1.2°F per decade on this date
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025warmest | 84° | 52° | 68° | — | — |
| 2024 | 73° | 42° | 58° | — | — |
| 2023 | 75° | 44° | 60° | — | — |
| 2022 | 54° | 40° | 47° | 2.72" | — |
| 2021 | 66° | 38° | 52° | — | — |
| 2020 | 60° | 50° | 55° | — | — |
| 2019 | 67° | 44° | 55° | — | — |
| 2018 | 68° | 48° | 58° | — | — |
| 2017 | 82° | 50° | 66° | — | — |
| 2016 | 63° | 56° | 59° | 0.03" | — |
| 2015 | 62° | 43° | 52° | 0.15" | — |
| 2014 | 68° | 54° | 61° | — | — |
| 2013 | 72° | 35° | 53° | — | — |
| 2012 | 73° | 45° | 59° | — | — |
| 2011 | 59° | 34° | 46° | — | — |
| 2010 | 78° | 47° | 62° | — | — |
| 2009 | 55° | 46° | 51° | 1.02" | — |
| 2008 | 79° | 49° | 64° | — | — |
| 2007 | 61° | 42° | 51° | — | — |
| 2006 | 64° | 48° | 56° | — | — |
| 2005 | 73° | 43° | 58° | — | — |
| 2004 | 83° | 46° | 64° | — | — |
| 2003 | 59° | 41° | 50° | — | — |
| 2002 | 70° | 44° | 57° | — | — |
| 2001 | 59° | 37° | 48° | — | — |
| 2000 | 62° | 42° | 52° | — | — |
| 1999 | 67° | 46° | 56° | — | — |
| 1998 | 68° | 34° | 51° | — | — |
| 1983 | 59° | 36° | 47° | — | — |
| 1982 | 74° | 46° | 60° | — | — |
| 1981 | 63° | 44° | 53° | — | — |
| 1980 | 80° | 52° | 66° | — | — |
| 1979 | 63° | 43° | 53° | — | — |
| 1978 | 74° | 43° | 58° | — | — |
| 1977 | 62° | 43° | 52° | — | — |
| 1976 | 71° | 42° | 57° | — | — |
| 1975 | 63° | 43° | 53° | — | — |
| 1974 | 63° | 37° | 50° | — | — |
| 1973 | 67° | 45° | 56° | — | — |
| 1972coldest | 48° | 29° | 38° | — | — |
| 1971 | 54° | 34° | 44° | — | — |
41 years of data from ONTARIO INTL AP