Ontario (CA)
August
Weather in Ontario, California for August 2026
Your guide to Ontario weather in August - trends and predictions
In general, the average temperature in Ontario at the beginning of August is 34.6 °F. As the month progressed, temperatures tended to moderately fall, reaching an average of 34 °F by the end of August.
With an average of 3 rainy days, Ontario experiences minimal rainfall in August.
New! Chat with our AI weatherman - it’s amazing and free.
Temperatures
Rain 🌧️
More
28
Dry days
3
Rainy days
0
Snow days
33°/19°
Temperatures
16 km/h
Avg max wind
37 %
Avg humidity
Ontario Weather August
Move between months or click on a day
Temperatures trend during August in Ontario
See the weather trend as well as the moving average line
August weather in Ontario day by day
Click on a date for more information
| Date | Weather | Temperatures | Rain | UV | More |
|---|---|---|---|---|---|
| Aug. 1 |  Overcast | 33° /21° | 0 mm | 7 | |
| Aug. 2 |  Sunny | 35° /19° | 0 mm | 9 | |
| Aug. 3 | Sunny | 34° /19° | 0 mm | 8 | |
| Aug. 4 | Sunny | 34° /19° | 0 mm | 8 | |
| Aug. 5 | Sunny | 36° /20° | 0 mm | 9 | |
| Aug. 6 | Sunny | 35° /21° | 0 mm | 9 | |
| Aug. 7 | Sunny | 35° /20° | 0 mm | 9 | |
| Aug. 8 | Sunny | 35° /19° | 0 mm | 8 | |
| Aug. 9 |  Heavy rain at times | 33° /20° | 1.2 mm | 8 | |
| Aug. 10 | Sunny | 32° /20° | 0.1 mm | 8 | |
| Aug. 11 | Sunny | 31° /19° | 0 mm | 8 | |
| Aug. 12 | Sunny | 32° /18° | 0 mm | 8 | |
| Aug. 13 | Sunny | 32° /18° | 0 mm | 8 | |
| Aug. 14 | Sunny | 34° /18° | 0 mm | 8 | |
| Aug. 15 | Sunny | 34° /18° | 0 mm | 8 | |
| Aug. 16 | Sunny | 33° /18° | 0 mm | 8 | |
| Aug. 17 | Sunny | 34° /18° | 0 mm | 8 | |
| Aug. 18 | Sunny | 34° /17° | 0 mm | 8 | |
| Aug. 19 | Sunny | 32° /19° | 0 mm | 8 | |
| Aug. 20 |  Moderate or heavy rain shower | 31° /19° | 37.8 mm | 8 | |
| Aug. 21 | Sunny | 33° /19° | 9.2 mm | 8 | |
| Aug. 22 | Sunny | 33° /18° | 0 mm | 8 | |
| Aug. 23 | Sunny | 32° /17° | 0 mm | 8 | |
| Aug. 24 | Sunny | 31° /18° | 0 mm | 8 | |
| Aug. 25 |  Partly cloudy | 34° /18° | 0 mm | 8 | |
| Aug. 26 | Sunny | 33° /18° | 0 mm | 8 | |
| Aug. 27 | Sunny | 34° /18° | 0 mm | 8 | |
| Aug. 28 | Sunny | 33° /20° | 0 mm | 8 | |
| Aug. 29 | Sunny | 35° /20° | 0 mm | 8 | |
| Aug. 30 | Sunny | 35° /20° | 0 mm | 9 | |
| Aug. 31 | Sunny | 34° /21° | 0 mm | 8 | |
| Next | |||||
Important Notice
Our weather forecast for Ontario in August is based on the analysis of historical data rather than real-time forecast models. While this provides a general overview, weather conditions can change. We recommend that you check the Ontario forecast closer to your planned date for the most up-to-date weather information.
Change Month
Ontario in August - FAQ
What are the expected maximum and minimum temperatures in Ontario during August?
Expect warm days with temperatures around 33°, cooling to mild conditions of 19° after sunset. Perfect for those who enjoy warm weather.
How much rainfall should be expected in Ontario during August?
Moderate rainfall is anticipated in Ontario during August, with a total of 53.6 mm spread over approximately 3 days. Considering plans for rainy days is advisable.
What are the typical wind conditions in Ontario during August?
The average wind speed in Ontario during August is 16 km/h, suggesting breezy to windy conditions, depending on your activities.
August rainfall patterns in Ontario
Explore the daily rainfall trends and prepare for Ontarios August weather 💧
UV exposure in Ontario during August
Stay informed about UV levels for safe outdoor activities throughout the month of August ☀️
Quick links
More Ontario weather pages
You are here
Where is Ontario?Get accurate weather forecasts for Ontario, located at latitude 34.063 and longitude -117.651. Stay updated with localized weather information tailored for Ontario.
Found a mistake?
We appreciate your attention to details. Tell us here.