What is the air quality trend in Waterloo?

Over the past 6 days, Waterloo had an average AQI of 47 based on station measurements. The worst day was 2026-07-18 with AQI 56.

How is Waterloo air quality measured?

Air quality in Waterloo 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 Waterloo, United States

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

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

Current AQI
Good CAMS model

48 Hours 7 Days 14 Days 20 Days

CSV JSON

Air Quality Index Station

38h

PM2.5 Station

38h · 1 station

Temperature GFS model

28pt

Precipitation GFS model

mm/day

Daily Summary Station

Date	AQI	Range	PM2.5 avg	Hours	Stations
2026-07-21	45	25–64	11.8 µg/m³	9h	1
2026-07-20	46	5–68	12.8 µg/m³	7h	1
2026-07-19	52	16–93	15.3 µg/m³	8h	1
2026-07-18	56	4–144	19.1 µg/m³	7h	1
2026-07-16	37	13–83	10.7 µg/m³	4h	1
2026-07-15	51	42–59	13.0 µg/m³	3h	1

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