Today | Weather | Sunday, April 26, 2026

Weather in Rancho Cucamonga, California

09:57 AM
Now
Partly Sunny with Showers
57° F
Feels Like 54°
Precipitation 51 %
Wind 9 mph
UV Index (0 - 11+) 2
Humidity 70 %
Today
Cloudy Weather
Day 64°
Night 50°
Precipitation 55 %
Wind 12 mph
UV Index (0 - 11+) 5

Rancho Cucamonga Weather Forecast Updated

48 minutes ago
Last updated on
Weather Forecast History
Last Year's Weather on This Day (April 26, 2025)
Stormy Weather

Day

55°

Night

46°

Wind

8 mph

UV Index

3

Precipitation

99 %

Air Quality in Rancho Cucamonga

NOW
57 AQI
Moderate air quality Dominant pollutant: O3

Pollutant Concentrations:

PM2.5 0.5 µg/m³
PM10 1.03 µg/m³
O3 0.056 ppm
NO2 0.2 ppb
SO2 0.1 ppb
CO 0.11 ppm
NH3 0.01 µg/m³
NO 0.05 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)
PM2.50.5 µg/m³
PM101.03 µg/m³
O3110.66 µg/m³
NO20.34 µg/m³
SO20.36 µg/m³
CO126.62 µg/m³
NH30.01 µg/m³
NO0.05 µg/m³