What is the air quality trend in Norwalk?

Over the past 8 days, Norwalk had an average AQI of 84 based on station measurements. The worst day was 2026-07-17 with AQI 118.

How is Norwalk air quality measured?

Air quality in Norwalk 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 Norwalk, United States

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

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

Current AQI
Good CAMS model

48 Hours 7 Days 14 Days 20 Days

CSV JSON

Air Quality Index Station

167h

PM2.5 Station

167h · 2 stations

Temperature GFS model

28pt

Precipitation GFS model

mm/day

Daily Summary Station

Date	AQI	Range	PM2.5 avg	PM10 avg	Hours	Stations
2026-07-22	33	30–35	7.8 µg/m³	1.0	3h	4
2026-07-21	61	38–95	17.6 µg/m³	117.9	24h	6
2026-07-20	61	23–101	18.5 µg/m³	149.0	24h	5
2026-07-19	75	41–111	23.8 µg/m³	102.8	24h	5
2026-07-18	117	76–156	43.1 µg/m³	125.2	24h	5
2026-07-17	118	47–174	49.6 µg/m³	122.2	24h	4
2026-07-16	115	64–182	46.5 µg/m³	138.1	24h	4
2026-07-15	98	26–165	36.4 µg/m³	102.6	20h	3

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