What is the air quality trend in Alliston?

Over the past 8 days, Alliston had an average AQI of 73 based on station measurements. The worst day was 2026-07-16 with AQI 102.

How is Alliston air quality measured?

Air quality in Alliston 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 Alliston, Canada

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

Historical PM2.5 and AQI trend from monitoring stations near Alliston, Canada.

Current AQI
Moderate Station

48 Hours 7 Days 14 Days 20 Days

CSV JSON

Air Quality Index Station

167h

PM2.5 Station

167h · 6 stations

Temperature GFS model

28pt

Precipitation GFS model

mm/day

Daily Summary Station

Date	AQI	Range	PM2.5 avg	Hours	Stations
2026-07-21	71	53–115	21.7 µg/m³	20h	5
2026-07-20	29	18–58	7.1 µg/m³	24h	4
2026-07-19	43	20–75	11.2 µg/m³	24h	5
2026-07-18	91	23–148	31.0 µg/m³	24h	4
2026-07-17	81	31–167	28.7 µg/m³	24h	6
2026-07-16	102	60–185	38.5 µg/m³	24h	7
2026-07-15	83	42–147	27.0 µg/m³	24h	6
2026-07-14	84	64–101	27.6 µg/m³	3h	4

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