Weather on June 18
Ontario, CA
55 Years of Data
Avg High
86°F
Avg Low
58°F
Warmest
1981
85°F avg
Coldest
1975
55°F avg
About This Date
June 18th in Ontario, CA typically brings warm summer weather, with average highs around 86°F and lows near 58°F — a 28°F daily swing. Over 42 years of records, the warmest June 18th was in 1981 (85°F average), while the coldest was 1975 (55°F) — a 30°F range across recorded history. Rain or other precipitation has occurred on about 2% of June 18th dates historically. The last decade has been 2.0°F warmer on this date compared to 20-30 years ago.
The last decade has been 2.0°F warmer on this date compared to 20-30 years ago.
Planning for June 18th 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 |
|---|---|---|---|---|---|
| 2025 | 96° | 65° | 80° | — | — |
| 2024 | 83° | 60° | 71° | — | — |
| 2023 | 81° | 59° | 70° | — | — |
| 2022 | 80° | 59° | 70° | — | — |
| 2021 | 94° | 68° | 81° | — | — |
| 2020 | 77° | 59° | 68° | — | — |
| 2019 | 82° | 64° | 73° | — | — |
| 2018 | 79° | 58° | 68° | — | — |
| 2017 | 97° | 65° | 81° | — | — |
| 2016 | 99° | 60° | 79° | — | — |
| 2015 | 98° | 62° | 80° | — | — |
| 2014 | 84° | 57° | 71° | — | — |
| 2013 | 88° | 61° | 74° | — | — |
| 2012 | 88° | 58° | 73° | — | — |
| 2011 | 81° | 59° | 70° | — | — |
| 2010 | 82° | 57° | 70° | — | — |
| 2009 | 87° | 58° | 72° | — | — |
| 2008 | 103° | 65° | 84° | — | — |
| 2007 | 89° | 58° | 73° | — | — |
| 2006 | 90° | 64° | 77° | — | — |
| 2005 | 79° | 56° | 67° | — | — |
| 2004 | 82° | 58° | 70° | — | — |
| 2003 | 80° | 61° | 70° | — | — |
| 2002 | 89° | 60° | 75° | — | — |
| 2001 | 94° | 61° | 77° | — | — |
| 2000 | 83° | 61° | 72° | — | — |
| 1999 | 92° | 58° | 75° | — | — |
| 1998 | 87° | 56° | 71° | — | — |
| 1984 | 94° | 56° | 75° | — | — |
| 1983 | 87° | 56° | 71° | — | — |
| 1982 | 66° | 56° | 61° | — | — |
| 1981warmest | 104° | 66° | 85° | — | — |
| 1980 | 87° | 56° | 71° | — | — |
| 1979 | 75° | 52° | 63° | — | — |
| 1978 | 95° | 61° | 78° | — | — |
| 1977 | 85° | 50° | 67° | — | — |
| 1976 | 90° | 51° | 70° | — | — |
| 1975coldest | 61° | 50° | 55° | 0.15" | — |
| 1974 | 82° | 45° | 63° | — | — |
| 1973 | 93° | 51° | 72° | — | — |
| 1972 | 83° | 58° | 70° | — | — |
| 1971 | 86° | 54° | 70° | — | — |
42 years of data from ONTARIO INTL AP