Kingshuk Mondal / CC BY 4.0
Ontario, CA Weather on July 17
July 17th in Ontario, CA typically brings hot summer weather, with average highs around 93°F and lows near 63°F — a 30°F daily swing. Over 42 years of records, the warmest July 17th was in 2010 (87°F average), while the coldest was 1973 (68°F) — a 19°F range across recorded history. This date has historically been dry, with little recorded precipitation. The last decade has been 2.1°F warmer on this date compared to 20-30 years ago.
What to Expect on July 17
Planning for July 17th in Ontario, CA? Stay hydrated and seek shade during peak afternoon hours.
July 17 Weather Records for Ontario
- •The all-time record high for July 17th in Ontario, CA is 102°F, set in 1998.
- •The coldest July 17th on record dropped to 52°F in 1973.
- •Temperatures have reached 90°F or higher on July 17th in 33 of the last 42 years.
Frequently Asked Questions
What was the warmest July 17 ever in Ontario?
The warmest July 17 in Ontario, CA reached 102°F in 1998. That is 9°F above the long-term average high of 93°F.
What was the coldest July 17 ever in Ontario?
The coldest July 17 in Ontario, CA dropped to 52°F in 1973. That is 11°F below the long-term average low of 63°F.
What is the average temperature on July 17 in Ontario?
On July 17, Ontario averages a high of 93°F and a low of 63°F based on 42 years of NOAA weather observations from ONTARIO INTL AP.
How many years of weather data are available for July 17 in Ontario?
We have 42 years of weather records for July 17 in Ontario, CA, sourced from NOAA's Global Historical Climatology Network. Records include daily high and low temperatures, precipitation, and snowfall data going back to 2025.
July 17 Weather History in Ontario
| Year | High | Low | Precip | Snow |
|---|---|---|---|---|
| 2025 | 92°F | 63°F | 0" | -- |
| 2024 | 91°F | 66°F | 0" | -- |
| 2023 | 100°F | 72°F | 0" | -- |
| 2022 | 101°F | 70°F | 0" | -- |
| 2021 | 97°F | 67°F | 0" | -- |
| 2020 | 92°F | 63°F | 0" | -- |
| 2019 | 95°F | 66°F | 0" | -- |
| 2018 | 96°F | 67°F | 0" | -- |
| 2017 | 94°F | 67°F | 0" | -- |
| 2016 | 95°F | 62°F | 0" | -- |
| 2015 | 97°F | 62°F | 0" | -- |
| 2014 | 84°F | 63°F | 0" | -- |
| 2013 | 96°F | 63°F | 0" | -- |
| 2012 | 85°F | 59°F | 0" | -- |
| 2011 | 90°F | 58°F | 0" | -- |
| 2010 | 101°F | 74°F | 0" | -- |
| 2009 | 98°F | 70°F | 0" | -- |
| 2008 | 93°F | 70°F | 0" | -- |
| 2007 | 90°F | 62°F | 0" | -- |
| 2006 | 101°F | 71°F | 0" | -- |
| 2005 | 96°F | 65°F | 0" | -- |
| 2004 | 97°F | 69°F | 0" | -- |
| 2003 | 95°F | 69°F | 0" | -- |
| 2002 | 89°F | 63°F | 0" | -- |
| 2001 | 85°F | 57°F | 0" | -- |
| 2000 | 92°F | 58°F | 0" | -- |
| 1999 | 92°F | 61°F | 0" | -- |
| 1998 | 102°F | 69°F | 0" | -- |
| 1984 | 98°F | 68°F | 0" | -- |
| 1983 | 87°F | 54°F | 0" | -- |
| 1982 | 90°F | 53°F | 0" | -- |
| 1981 | 93°F | 61°F | 0" | -- |
| 1980 | 98°F | 60°F | 0" | -- |
| 1979 | 101°F | 68°F | 0" | -- |
| 1978 | 95°F | 61°F | 0" | -- |
| 1977 | 94°F | 64°F | 0" | -- |
| 1976 | 82°F | 55°F | 0" | -- |
| 1975 | 83°F | 59°F | 0" | -- |
| 1974 | 95°F | 58°F | 0" | -- |
| 1973 | 84°F | 52°F | 0" | -- |
| 1972 | 86°F | 56°F | 0" | -- |
| 1971 | 93°F | 62°F | 0" | -- |
Based on 42 years of data from NOAA station: ONTARIO INTL AP
Monthly Climate Averages
Historical temperature and precipitation averages for Ontario, CA, based on 55+ years of weather data.
Temperatures in Fahrenheit. Precipitation and snowfall in inches.