Today | Weather | Tuesday, April 21, 2026

Weather in Santa Clara, California

03:14 PM
Now
Stormy Weather
61° F
Feels Like 54°
Precipitation 79 %
Wind 12 mph
UV Index (0 - 11+) 1
Humidity 70 %
Today
Stormy Weather
Day 61°
Night 50°
Precipitation 97 %
Wind 9 mph
UV Index (0 - 11+) 3

Santa Clara Weather Forecast Updated

Last updated on
Weather Forecast History
Last Year's Weather on This Day (April 21, 2025)
Sunny Weather

Day

79°

Night

52°

Wind

7 mph

UV Index

9

Precipitation

0 %

Air Quality in Santa Clara

NOW
49 AQI
Good air quality Dominant pollutant: O3

Pollutant Concentrations:

PM2.5 0.57 µg/m³
PM10 1.43 µg/m³
O3 0.052 ppm
NO2 0.1 ppb
SO2 0.1 ppb
CO 0.12 ppm
NH3 0 µg/m³
NO 0.04 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 considered satisfactory, and air pollution poses little or no risk.

Show raw pollutant concentrations (µg/m³)
PM2.50.57 µg/m³
PM101.43 µg/m³
O3102.92 µg/m³
NO20.25 µg/m³
SO20.37 µg/m³
CO141.17 µg/m³
NH30 µg/m³
NO0.04 µg/m³