Ontario, California enjoys a comfortable Mediterranean climate that attracts both residents and visitors year-round.
The hottest month in Ontario is August, with average high temperatures reaching 93°F and lows around 66°F.
This makes summer a warm yet pleasant season for outdoor activities.
During the cooler months, from November to March, the average daily high temperatures fall below 71°F.
Rainfall is sparse throughout the year, with Ontario receiving about 16 inches of rain annually, which is significantly lower than the U.S. average.
This low rainfall and mild winter make the city a great destination for those looking to escape harsher climates.
Despite the variability in temperatures, Ontario typically experiences 279 sunny days annually, ensuring plenty of sunlight for outdoor enthusiasts.
Weather reports and climate data indicate a pattern of predictable weather conditions, perfect for planning activities and events throughout the year.
For more detailed breakdown, monthly averages and weather data can be explored further to better understand the climate in Ontario.
Average Temperature in Ontario, California
Ontario, California experiences varied temperatures throughout the year.
Summers:
- June: Average high is around 88°F.
- July: Daily highs can reach up to 92°F.
- August: The hottest month with average highs of 93°F and lows of 66°F.
Winters:
- December: Colder months start, averaging high temperatures of 68°F and lows of 46.6°F.
- January: The month tends to stay cool, with highs near 66°F.
Spring:
- March: Experience a mild climate with highs of 68°F.
- April: Slightly warmer, reaching average highs of 72.9°F.
Autumn:
- September: End of the hot season, with highs around 88°F.
- November: Temperatures drop further, with average highs of 71°F.
Using this detailed information, readers can better understand the average temperature in Ontario, California.
This gives a clearer picture of the variation seen between summer and winter months, and the transitional weather in between.
Average Precipitation In Ontario, California
Ontario, California experiences varied precipitation throughout the year. Rainfall is concentrated in certain months, while snowfall is rare due to the warm climate.
Average Rainfall In Ontario, California
Ontario’s rainfall patterns are influenced by its Mediterranean climate. Most rain falls during the winter months.
February is typically the wettest month, averaging about 1.77 inches of precipitation over six days.
Summer months, especially June through September, are very dry with almost no rain.
This significant variation in rainfall impacts water resource planning and agriculture in the region.
The average annual rainfall in Ontario is around 13 inches, with nearly all of it occurring from late fall to early spring.
This seasonal concentration of rain defines the local environment and affects everything from landscaping choices to wildfire risks during dry periods.
Average Snow In Ontario, California
Snowfall in Ontario is extremely rare owing to its mild temperatures.
The average daily high in winter remains well above freezing, typically around 60°F to 70°F.
Even in January, the coolest month, temperatures do not drop low enough for snow to form.
As a result, Ontario does not have any significant snowfall records.
The absence of snow shifts the focus to rain as the primary form of [precipitation].
Local residents and visitors should not expect snowy conditions but should prepare for rainy days during the winter months.
Average Sun In Ontario, California
Ontario, California enjoys plenty of sunshine throughout the year.
The city experiences varying amounts of daylight, with the shortest days in winter and the longest days in summer.
Patterns of sunlight influence the weather and daily routines in the area.
Average Daily Shortwave Solar Energy In Ontario, California
Ontario, California receives considerable shortwave solar energy throughout the year.
On average, there are around 7.56 hours of sunshine per day during January.
During summer, the hours increase significantly, with the longest days often having over 14 hours of daylight.
In terms of total yearly sunlight, Ontario enjoys around 3,457 hours.
The highest UV index levels occur during summer months, which is essential information for anyone spending extended periods outdoors during this time.
More information can be found on Ontario’s climate and sun patterns.
Average Humidity In Ontario, California
Ontario, California experiences a range of humidity levels throughout the year.
Humidity is generally lower during summer months when the weather is hot and dry.
The average relative humidity in summer can drop to around 20-30%.
During winter, the humidity often increases, reaching around 50-60%.
Here’s a quick look at the average humidity for different months:
- January: 60%
- April: 50%
- July: 30%
- October: 40%
The dew point varies too.
In the summer, it often stays around 50°F, making it feel quite dry.
In contrast, the winter dew point can be around 40°F, adding a slight chill to the air.
Cloud cover and partly cloudy days also affect humidity.
Summer has more clear days, while winter sees more partly cloudy skies.
This variation impacts the daily humidity levels, adding to the seasonal differences in how the air feels.
For detailed climate data, you can visit Climate and Average Weather Year Round in Ontario California and Weather Ontario & temperature by month.
Average Wind In Ontario, California
Wind in Ontario, California varies through the year but generally remains mild.
Wind Speed:
The average wind speed in Ontario is around 9 mph. It does not usually see extreme wind conditions, making the area relatively calm.
Windiest Month:
The windiest month typically is May, with an average wind speed reaching about 10 mph.
This is slightly higher than the rest of the year but still within a moderate range.
Wind Conditions:
During the calmest months, like December, the wind speed averages about 7 mph.
Even then, it provides a pleasant breeze rather than strong gusts.
Here is a quick overview:
| Month | Average Wind Speed (mph) |
|---|---|
| January | 8 |
| May | 10 |
| December | 7 |
The consistency of the wind ensures a balanced climate that supports various outdoor events throughout the year.
Average Air Quality In Ontario, California
Ontario, California experiences varied air quality throughout the year. The city often encounters different levels of air pollution, impacting residents’ health and visibility.
Air Quality Index (AQI)
The Air Quality Index (AQI) in Ontario fluctuates. It can range from “Good” to “Unhealthy.”
- Good: 0-50 AQI, suitable for outdoor activities.
- Moderate: 51-100 AQI, sensitive individuals should limit outdoor exertion.
- Unhealthy for Sensitive Groups: 101-150 AQI, consider reducing prolonged outdoor exertion.
Typical Pollutants
Key pollutants include PM2.5, ozone, and nitrogen dioxide.
PM2.5 levels can rise due to wildfires and vehicle emissions, especially during summer.
The region’s air quality can be monitored in real-time on platforms like IQAir.
Meteorological Conditions
- Temperature: Ontario averages temperatures of 93.2°F in summer and 73.4°F in winter.
- Pressure: Varied atmospheric pressures influence pollutant dispersion.
- Visibility: Poor air quality can reduce visibility, especially during pollution episodes.
Maintaining awareness of daily air quality can help residents take preventive measures to protect their health.
Websites like The Weather Channel provide useful data and forecasts.
Topography Of Ontario, California
Ontario, California lies in the Inland Empire region.
Its elevation varies slightly, averaging around 1,004 feet above sea level. This elevation offers a unique blend of valley and slight upland characteristics.
The city’s topography includes flat plains and gentle hills.
These features provide varied landscapes, from urban areas to open parks and natural reserves.
The Santa Ana Mountains to the southwest and Mount Baldy to the north offer prominent topographical landmarks.
These mountains provide scenic views and influence local climate patterns.
Many parts of Ontario are built on alluvial plains. These plains were formed by sediment deposited by rivers, contributing to the fertile land.
Ontario’s location within the San Bernardino Valley means it benefits from the natural protection offered by surrounding mountain ranges.
Rainfall runoff is managed by a system of natural and man-made channels.
This system helps prevent flooding in the flat regions.
Extreme Weather Events That Occur In Ontario, California
Ontario, California experiences a variety of extreme weather events. These events can significantly impact daily life, causing disruptions and potential hazards.
Flooding
Flooding is a common extreme weather event in Ontario.
Heavy rains, especially during the winter, can lead to significant water accumulation. Streets and properties often experience water damage.
Heatwaves
Ontario frequently faces intense heatwaves during the summer.
Temperatures can soar to over 100°F for extended periods, increasing the risk of heat-related illnesses.
Windstorms
High winds are another issue for Ontario.
These storms can cause power outages, topple trees, and scatter debris. The Santa Ana winds are particularly notorious for their strength and dryness.
Electrical Storms
Electrical storms, which often include thunder and lightning, are also observed. These storms can be dangerous, with lightning leading to fires and electrical hazards.
More information on these storms can be found in this article.
Hail
Although less frequent, hailstorms can occur. Hailstones, sometimes reaching the size of golf balls, can cause damage to vehicles, windows, and roofs.
Extreme weather events in Ontario, California include a mix of natural occurrences that require preparation and awareness for safety.
Best Time Of The Year To Visit Ontario, California
The best time to visit Ontario, California, usually depends on the weather preferences of the visitor. The city experiences varying weather conditions throughout the year, making each season unique. Here’s what each season has to offer:
What Is Ontario, California Like In Spring
In spring, Ontario experiences mild and pleasant weather. Average daily temperatures range from 70°F to 80°F.
This is a comfortable time for outdoor activities like hiking and visiting local parks. Rainfall is relatively low, averaging about 1 to 2 inches per month.
Flowers are in bloom, and the city’s landscapes are vibrant.
This season is ideal for those who want to enjoy the outdoors without extreme heat or cold.
Events such as local markets and festivals often take place during this time, attracting both tourists and locals.
What Is Ontario, California Like In Summer
Summer in Ontario is hot, with average daily high temperatures from 90°F to 95°F. The warmest month is August, where temperatures can peak at 98°F.
Despite the heat, humidity levels remain low, making the heat more bearable.
Because of the heat, visitors should stay hydrated and plan indoor activities.
This season is perfect for poolside relaxation at hotels or visiting air-conditioned attractions. Light clothing and sun protection are recommended.
What Is Ontario, California Like In Fall
Fall brings cooler temperatures, making it another comfortable time to visit Ontario. Average daily temperatures range from 70°F to 85°F.
Rainfall remains low, with an average of 1 inch per month. The weather is stable, and the skies are clear.
Tourists can enjoy various outdoor activities such as hiking and visiting vineyards.
Fall festivals and local events add to the charm, offering a glimpse into the local culture.
What Is Ontario, California Like In Winter
Winter in Ontario is mild compared to many other places.
Average daily high temperatures range from 60°F to 70°F, with nighttime lows around 40°F.
While temperatures are cooler, it rarely gets cold enough for snow.
Rainfall increases slightly, ranging from 2 to 3 inches per month.
This season is good for visitors who prefer milder weather and fewer crowds.
Winter holidays bring festive decorations and events, making the city a lovely place to visit during this time.