Weather on October 17
Ontario, CA
55 Years of Data
Avg High
81°F
Avg Low
55°F
Warmest
2012
81°F avg
Coldest
1971
47°F avg
About This Date
October 17th in Ontario, CA typically brings warm fall weather, with average highs around 81°F and lows near 55°F — a 26°F daily swing. Over 41 years of records, the warmest October 17th was in 2012 (81°F average), while the coldest was 1971 (47°F) — a 34°F range across recorded history. Rain or other precipitation has occurred on about 10% of October 17th dates historically, with the wettest October 17th recording 2.21" of rain. The last decade has been 3.7°F warmer on this date compared to 20-30 years ago.
The last decade has been 3.7°F warmer on this date compared to 20-30 years ago.
Planning for October 17th in Ontario, CA? Stay hydrated and seek shade during peak afternoon hours.
Warming Trend
1.8°F per decade on this date
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 84° | 54° | 69° | — | — |
| 2024 | 68° | 60° | 64° | — | — |
| 2023 | 91° | 61° | 76° | — | — |
| 2022 | 83° | 57° | 70° | — | — |
| 2021 | 83° | 56° | 69° | — | — |
| 2020 | 94° | 64° | 79° | — | — |
| 2019 | 78° | 59° | 69° | — | — |
| 2018 | 84° | 52° | 68° | — | — |
| 2017 | 97° | 60° | 78° | — | — |
| 2016 | 74° | 59° | 66° | 0.15" | — |
| 2015 | 84° | 66° | 75° | — | — |
| 2014 | 78° | 58° | 68° | — | — |
| 2013 | 85° | 56° | 70° | — | — |
| 2012warmest | 101° | 61° | 81° | — | — |
| 2011 | 88° | 58° | 73° | — | — |
| 2010 | 65° | 60° | 62° | — | — |
| 2009 | 97° | 63° | 80° | — | — |
| 2008 | 95° | 58° | 76° | — | — |
| 2007 | 68° | 55° | 62° | — | — |
| 2006 | 72° | 53° | 62° | — | — |
| 2005 | 67° | 56° | 61° | 2.21" | — |
| 2004 | 67° | 58° | 62° | 0.18" | — |
| 2003 | 96° | 56° | 76° | — | — |
| 2002 | 68° | 56° | 62° | — | — |
| 2001 | 85° | 54° | 69° | — | — |
| 2000 | 89° | 52° | 70° | — | — |
| 1999 | 85° | 55° | 70° | — | — |
| 1998 | 82° | 52° | 67° | — | — |
| 1983 | 69° | 49° | 59° | — | — |
| 1982 | 85° | 49° | 67° | — | — |
| 1981 | 83° | 46° | 64° | — | — |
| 1980 | 72° | 42° | 57° | — | — |
| 1979 | 69° | 51° | 60° | — | — |
| 1978 | 78° | 51° | 65° | — | — |
| 1977 | 83° | 53° | 68° | — | — |
| 1976 | 81° | 50° | 65° | — | — |
| 1975 | 84° | 51° | 68° | — | — |
| 1974 | 93° | 55° | 74° | — | — |
| 1973 | 92° | 56° | 74° | — | — |
| 1972 | 68° | 50° | 59° | — | — |
| 1971coldest | 58° | 37° | 47° | 0.1" | — |
41 years of data from ONTARIO INTL AP