Today | Weather | Sunday, September 20, 2026

Weather in Santa Rosa, California

02:51 PM
Now
Cloudy Weather
73° F
Feels Like 75°
Precipitation 0 %
Wind 7 mph
UV Index (0 - 11+) 3
Humidity 54 %
Today
Cloudy Weather
Day 73°
Night 54°
Precipitation 0 %
Wind 6 mph
UV Index (0 - 11+) 5

Santa Rosa Weather Forecast Updated

14 minutes ago
Last updated on
Weather Forecast History
Last Year's Weather on This Day (September 20, 2025)
Cloudy Night

Day

81°

Night

54°

Wind

5 mph

Precipitation

1 %

Air Quality in Santa Rosa

NOW
41 AQI
Good air quality Dominant pollutant: O3

Pollutant Concentrations:

PM2.5 3.33 µg/m³
PM10 12.71 µg/m³
O3 0.045 ppm
NO2 0.2 ppb
SO2 0.2 ppb
CO 0.12 ppm
NH3 0 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 considered satisfactory, and air pollution poses little or no risk.

Show raw pollutant concentrations (µg/m³)
PM2.53.33 µg/m³
PM1012.71 µg/m³
O387.76 µg/m³
NO20.42 µg/m³
SO20.64 µg/m³
CO141.51 µg/m³
NH30 µg/m³
NO0.05 µg/m³