What is the air quality trend in Napa?

Over the past 15 days, Napa had an average AQI of 28 based on station measurements. The worst day was 2026-08-31 with AQI 34.

How is Napa air quality measured?

Air quality in Napa is measured by ground-level monitoring stations that report PM2.5 and PM10 concentrations hourly. CERNS.IO aggregates readings from nearby stations and converts PM2.5 to the US EPA Air Quality Index (AQI) scale.

Air Quality History for Napa, United States

Name: Napa Air Quality History
Creator: CERNS.IO
License: https://creativecommons.org/licenses/by/4.0/

Historical PM2.5 and AQI trend from monitoring stations near Napa, United States.

Current AQI
Good Station

48 Hours 7 Days 14 Days 20 Days

CSV JSON

Air Quality Index Station

333h

PM2.5 Station

333h · 21 stations

Temperature GFS model

56pt

Precipitation GFS model

mm/day

Daily Summary Station

Date	AQI	Range	PM2.5 avg	Hours	Stations
2026-09-05	33	21–109	8.7 µg/m³	15h	21
2026-09-04	27	17–50	6.4 µg/m³	24h	21
2026-09-03	25	20–31	5.9 µg/m³	24h	21
2026-09-02	29	23–42	6.8 µg/m³	24h	21
2026-09-01	28	16–41	6.8 µg/m³	24h	20
2026-08-31	34	28–44	8.2 µg/m³	24h	25
2026-08-30	33	28–38	7.9 µg/m³	24h	25
2026-08-29	28	22–37	6.8 µg/m³	24h	24
2026-08-28	27	21–37	6.5 µg/m³	24h	26
2026-08-27	26	18–37	6.2 µg/m³	24h	26
2026-08-26	25	18–34	6.0 µg/m³	24h	26
2026-08-25	23	18–28	5.5 µg/m³	24h	25
2026-08-24	27	19–38	6.4 µg/m³	24h	25
2026-08-23	27	22–36	6.5 µg/m³	24h	24
2026-08-22	28	25–30	6.7 µg/m³	6h	26

Back to Napa Air Quality