Today | Weather | Thursday, October 30, 2025

Weather in Ontario, California

11:31 AM
Now
Sunny Weather
82° F
Feels Like 88°
Precipitation 0 %
Wind 5 mph
UV Index (0 - 11+) 4
Humidity 16 %
Today
Sunny Weather
Day 90°
Night 57°
Precipitation 0 %
Wind 6 mph
UV Index (0 - 11+) 4

Ontario Weather Forecast Updated

30 minutes ago
Last updated on

Weather Forecast History

Last Year's Weather on This Day (October 30, 2024)

Cloudy Night

Day

72°

Night

48°

Wind

4 mph

Precipitation

0

Air Quality in Ontario

NOW
74 AQI
Moderate air quality Dominant pollutant: PM2.5

Pollutant Concentrations:

PM2.5 23.03 µg/m³
PM10 34.55 µg/m³
O3 0.044 ppm
NO2 0.5 ppb
SO2 0.2 ppb
CO 0.18 ppm
NH3 0.03 µg/m³
NO 0.17 µg/m³
PM2.5 – Fine particles <2.5μm
PM10 – Inhalable particles <10μm
O3 – Ozone
NO2 – Nitrogen dioxide
SO2 – Sulfur dioxide
CO – Carbon monoxide
NH3 – Ammonia
NO – Nitric oxide

Health Recommendations:

Air quality is acceptable; however, for some pollutants, there may be a moderate health concern for a very small number of people who are unusually sensitive to air pollution.

Show raw pollutant concentrations (µg/m³)
PM2.523.03 µg/m³
PM1034.55 µg/m³
O385.73 µg/m³
NO20.94 µg/m³
SO20.41 µg/m³
CO202.75 µg/m³
NH30.03 µg/m³
NO0.17 µg/m³