Today | Weather | Wednesday, May 20, 2026

Weather in Napa, California

02:50 PM
Now
Cloudy Weather
82° F
Feels Like 86°
Precipitation 0 %
Wind 10 mph
UV Index (0 - 11+) 7
Humidity 30 %
Today
Cloudy Weather
Day 84°
Night 52°
Precipitation 0 %
Wind 7 mph
UV Index (0 - 11+) 10

Warning: High UV Index Today: 10

High risk of harm from unprotected sun exposure. Take precautions: wear a hat, sunglasses, and apply sunscreen regularly if you’ll be outdoors for extended periods.

Napa Weather Forecast Updated

Last updated on

Air Quality in Napa

NOW
37 AQI
Good air quality Dominant pollutant: O3

Pollutant Concentrations:

PM2.5 4.69 µg/m³
PM10 12.01 µg/m³
O3 0.040 ppm
NO2 0.2 ppb
SO2 0.3 ppb
CO 0.09 ppm
NH3 0 µg/m³
NO 0.12 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)
PM2.54.69 µg/m³
PM1012.01 µg/m³
O378.62 µg/m³
NO20.4 µg/m³
SO20.8 µg/m³
CO108.45 µg/m³
NH30 µg/m³
NO0.12 µg/m³