Today | Weather | Saturday, September 19, 2026

Weather in Santa Clara, California

12:42 AM
Now
Cloudy Night
61° F
Feels Like 61°
Precipitation 0 %
Wind 4 mph
Humidity 84 %
Today
Cloudy Weather
Day 82°
Night 57°
Precipitation 0 %
Wind 7 mph
UV Index (0 - 11+) 5

Santa Clara Weather Forecast Updated

22 minutes ago
Last updated on
Weather Forecast History
Last Year's Weather on This Day (September 19, 2025)
Cloudy Night

Day

81°

Night

63°

Wind

6 mph

Precipitation

3 %

Air Quality in Santa Clara

NOW
42 AQI
Good air quality Dominant pollutant: O3

Pollutant Concentrations:

PM2.5 6.76 µg/m³
PM10 20.96 µg/m³
O3 0.046 ppm
NO2 0.4 ppb
SO2 0.3 ppb
CO 0.14 ppm
NH3 0 µg/m³
NO 0 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)
PM2.56.76 µg/m³
PM1020.96 µg/m³
O389.41 µg/m³
NO20.79 µg/m³
SO20.88 µg/m³
CO156.49 µg/m³
NH30 µg/m³
NO0 µg/m³