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 °C. As the month progressed, temperatures tended to moderately fall, reaching an average of 34 °C by the end of August.
With an average of 3 rainy days, Ontario experiences minimal rainfall in August.
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Temperatures
Rain 🌧️
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28
Dry days
3
Rainy days
0
Snow days
33°/19°
Temperatures
16 km/h
Avg max wind
39 %
Avg humidity
Ontario Weather August
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Temperatures trend during August in Ontario
See the weather trend as well as the moving average line
August weather in Ontario day by day
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| 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 | |
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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.
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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?
In August, Ontario can expect light to moderate rainfall, totaling 48.3 mm across approximately 3 days. Occasional showers are possible, and planning ahead for them could be helpful.
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 💧
Typically, Ontario has 3 rainy days in August with a total of 48.3 mm of rainfall.
UV exposure in Ontario during August
Stay informed about UV levels for safe outdoor activities throughout the month of August ☀️
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