Weather on May 19
Ontario, CA
55 Years of Data
Avg High
80°F
Avg Low
54°F
Warmest
2008
83°F avg
Coldest
1972
54°F avg
About This Date
May 19th in Ontario, CA typically brings warm spring weather, with average highs around 80°F and lows near 54°F — a 26°F daily swing. Over 41 years of records, the warmest May 19th was in 2008 (83°F average), while the coldest was 1972 (54°F) — a 29°F range across recorded history. Rain or other precipitation has occurred on about 5% of May 19th dates historically. The last decade has been 1.9°F cooler on this date compared to 20-30 years ago.
The last decade has been 1.9°F cooler on this date compared to 20-30 years ago.
Planning for May 19th in Ontario, CA? Stay hydrated and seek shade during peak afternoon hours.
Warming Trend
0.9°F per decade on this date
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 89° | 56° | 72° | — | — |
| 2024 | 75° | 55° | 65° | — | — |
| 2023 | 73° | 58° | 65° | — | — |
| 2022 | 77° | 57° | 67° | — | — |
| 2021 | 78° | 56° | 67° | — | — |
| 2020 | 73° | 53° | 63° | — | — |
| 2019 | 70° | 54° | 62° | 0.46" | — |
| 2018 | 71° | 57° | 64° | — | — |
| 2017 | 90° | 57° | 73° | — | — |
| 2016 | 79° | 59° | 69° | — | — |
| 2015 | 74° | 54° | 64° | — | — |
| 2014 | 78° | 58° | 68° | — | — |
| 2013 | 84° | 56° | 70° | — | — |
| 2012 | 86° | 54° | 70° | — | — |
| 2011 | 70° | 46° | 58° | — | — |
| 2010 | 79° | 56° | 67° | — | — |
| 2009 | 91° | 61° | 76° | — | — |
| 2008warmest | 97° | 69° | 83° | — | — |
| 2007 | 82° | 54° | 68° | — | — |
| 2006 | 86° | 59° | 73° | — | — |
| 2005 | 90° | 59° | 74° | — | — |
| 2004 | 77° | 56° | 66° | — | — |
| 2003 | 89° | 56° | 72° | — | — |
| 2002 | 70° | 56° | 63° | — | — |
| 2001 | 74° | 59° | 66° | — | — |
| 2000 | 93° | 58° | 75° | — | — |
| 1999 | 75° | 54° | 64° | — | — |
| 1984 | 92° | 50° | 71° | — | — |
| 1983 | 84° | 48° | 66° | — | — |
| 1982 | 78° | 55° | 67° | — | — |
| 1981 | 79° | 57° | 68° | — | — |
| 1980 | 86° | 54° | 70° | — | — |
| 1979 | 81° | 49° | 65° | — | — |
| 1978 | 91° | 59° | 75° | — | — |
| 1977 | 75° | 44° | 60° | — | — |
| 1976 | 77° | 45° | 61° | — | — |
| 1975 | 67° | 49° | 58° | — | — |
| 1974 | 66° | 42° | 54° | — | — |
| 1973 | 74° | 55° | 64° | — | — |
| 1972coldest | 61° | 47° | 54° | 0.18" | — |
| 1971 | 87° | 52° | 69° | — | — |
41 years of data from ONTARIO INTL AP