Weather on May 11
Ontario, CA
55 Years of Data
Avg High
80°F
Avg Low
52°F
Warmest
2025
81°F avg
Coldest
1980
50°F avg
About This Date
May 11th in Ontario, CA typically brings warm spring weather, with average highs around 80°F and lows near 52°F — a 28°F daily swing. Over 41 years of records, the warmest May 11th was in 2025 (81°F average), while the coldest was 1980 (50°F) — a 31°F range across recorded history. Rain or other precipitation has occurred on about 5% of May 11th dates historically. The last decade has been 2.2°F warmer on this date compared to 20-30 years ago.
The last decade has been 2.2°F warmer on this date compared to 20-30 years ago.
Planning for May 11th in Ontario, CA? Stay hydrated and seek shade during peak afternoon hours.
Warming Trend
1.2°F per decade on this date
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025warmest | 97° | 65° | 81° | — | — |
| 2024 | 81° | 57° | 69° | — | — |
| 2023 | 73° | 53° | 63° | — | — |
| 2022 | 71° | 46° | 59° | — | — |
| 2021 | 83° | 56° | 69° | — | — |
| 2020 | 81° | 58° | 69° | — | — |
| 2019 | 82° | 59° | 71° | — | — |
| 2018 | 67° | 56° | 61° | — | — |
| 2017 | 79° | 56° | 67° | — | — |
| 2016 | 83° | 58° | 70° | — | — |
| 2015 | 86° | 57° | 72° | — | — |
| 2014 | 84° | 50° | 67° | — | — |
| 2013 | 97° | 60° | 78° | — | — |
| 2012 | 80° | 56° | 68° | — | — |
| 2011 | 76° | 51° | 63° | — | — |
| 2010 | 69° | 49° | 59° | — | — |
| 2009 | 83° | 55° | 69° | 0.08" | — |
| 2008 | 75° | 53° | 64° | — | — |
| 2007 | 84° | 54° | 69° | — | — |
| 2006 | 87° | 56° | 71° | — | — |
| 2005 | 78° | 50° | 64° | — | — |
| 2004 | 75° | 56° | 65° | — | — |
| 2003 | 81° | 51° | 66° | — | — |
| 2002 | 77° | 53° | 65° | — | — |
| 2001 | 87° | 55° | 71° | — | — |
| 2000 | 73° | 54° | 63° | — | — |
| 1999 | 81° | 51° | 66° | — | — |
| 1984 | 91° | 51° | 71° | — | — |
| 1983 | 73° | 40° | 56° | — | — |
| 1982 | 61° | 47° | 54° | — | — |
| 1981 | 88° | 50° | 69° | — | — |
| 1980coldest | 59° | 41° | 50° | 0.13" | — |
| 1979 | 88° | 49° | 68° | — | — |
| 1978 | 79° | 54° | 66° | — | — |
| 1977 | 65° | 42° | 53° | — | — |
| 1976 | 89° | 53° | 71° | — | — |
| 1975 | 83° | 48° | 65° | — | — |
| 1974 | 77° | 48° | 63° | — | — |
| 1973 | 80° | 49° | 64° | — | — |
| 1972 | 87° | 48° | 68° | — | — |
| 1971 | 77° | 49° | 63° | — | — |
41 years of data from ONTARIO INTL AP