All Countries
Ontario, CA
Full City Profile · California · Orange County County
2.6
/5.0
C+
Fair
178,347
Population
3,568/sq mi density
$82,806
Median Income
$31,141 per capita
$568,000
Home Value
$665,551 Zillow
$1,916
Median Rent
35.3% income on rent
64°F
Avg Temperature
329 sunny days/yr
359
Violent Crime/100K
2,340 property/100K
C+
Overall
2.6 / 5.0
Fair overall score based on economy, affordability, safety and education
A
Economy
4.1 / 5.0
$82,806 median income, 3.9% unemployment
C+
Affordability
2.8 / 5.0
$568,000 home value, $1,916/mo rent
F
Safety
1.0 / 5.0
359 violent crimes/100K
C+
Education
2.7 / 5.0
20.7% bachelor's degree or higher
Ontario enjoys a temperate climate with an average annual temperature of 64°F (18°C). Winters average 51°F in January while summers reach 80°F in July. The area gets 329 sunny days per year. Annual precipitation totals 38.3 inches. The area receives 6.8 inches of snow annually. Air quality is rated Good with a median AQI of 48.
Temperature
51°F Jan (10°C)
80°F Jul (27°C)
| Annual Average | 63.5°F |
| 18% above US avg | |
| January Average | 51°F (10°C) |
| July Average | 80°F (27°C) |
| Sunny Days | 329 days/yr |
Geography
| Elevation | 856 ft (261 m) |
| Area | 50.0 sq mi (129.5 km²) |
| Population Density | 3,568/sq mi |
| Coordinates | 34.0376°N, 117.6044°W |
| Timezone | America/Los_Angeles |
| County | Orange County County |
| Nearest Airport | Ontario International (ONT) 1 miles away |
Precipitation & Snow
Air Quality
| AQI Median | 48.0 |
| Rating | Good |
Air Pollutants (EPA 2023)
| Ozone (O₃) | 0.0440 ppm |
| NO₂ (Nitrogen Dioxide) | 18.4 ppb |
| CO (Carbon Monoxide) | 0.35 ppm |
| PM2.5 (Fine Particles) | 9.7 μg/m³ |
Natural Hazard Risk
| Overall Risk | Very High |
| Risk Score | 99.8 / 100 |
| Social Vulnerability | 24.9 / 100 |
| Community Resilience | 16.3 / 100 |
Hazard Breakdown
| Tornado | Relatively Moderate |
| Hurricane | No Rating |
| Earthquake | Very High |
| Wildfire | Relatively High |
| Flood | Very High |
| Hail | Relatively Moderate |
| Strong Wind | Relatively Moderate |
| Heat Wave | Relatively High |
| Winter Weather | Very Low |
| Lightning | Relatively Moderate |
| Drought | Relatively Low |
| Cold Wave | No Rating |
| Landslide | Relatively High |
| Coastal Flood | Relatively High |
| Tsunami | Relatively Low |
| Avalanche | Very Low |
Source: FEMA National Risk Index v1.20 (Dec 2025)
Tsunami History
3 tsunamis recorded within 500 km. Highest wave on record: 3.1 m (10 ft).
| Year | Location | Cause | Max Wave | Deaths | Distance |
| 1930 | S. CALIFORNIA | Eruption + Earthquake | 3.1 m | 1 | 96 km |
| 1994 | WEST COAST, USA | Earthquake | 0.1 m | 57 | 88 km |
| 1855 | S. CALIFORNIA | Eruption + Earthquake | - | - | 46 km |
Source: NOAA/NCEI Historical Tsunami Database. Sorted by wave height.
Monthly Weather
| Month | Avg Temperature | Precipitation | Summary |
|---|---|---|---|
| January | 51°F (10°C) | 3.0 in | Coldest |
| February | 56°F (13°C) | 3.1 in | Wettest |
| March | 57°F (14°C) | 2.7 in | |
| April | 61°F (16°C) | 1.0 in | |
| May | 65°F (19°C) | 0.3 in | |
| June | 71°F (22°C) | 0.0 in | Driest |
| July | 80°F (27°C) | 0.0 in | Warmest |
| August | 77°F (25°C) | 0.2 in | |
| September | 74°F (23°C) | 0.4 in | |
| October | 67°F (20°C) | 0.4 in | |
| November | 59°F (15°C) | 1.6 in | |
| December | 54°F (12°C) | 2.0 in |
Ontario has a seasonal temperature swing of 29°F / from 51°F in January to 80°F in July. Total annual precipitation is 14.7 inches, with February being the wettest month (3.1") and June the driest (0.0").