What is the air quality trend in Sarnia?

Over the past 13 days, Sarnia had an average AQI of 77 based on station measurements. The worst day was 2026-07-17 with AQI 311.

How is Sarnia air quality measured?

Air quality in Sarnia 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 Sarnia, Canada

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

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

Current AQI
Good Station

48 Hours 7 Days 14 Days 20 Days

CSV JSON

Air Quality Index Station

93h

PM2.5 Station

93h · 1 station

Temperature GFS model

56pt

Precipitation GFS model

mm/day

Daily Summary Station

Date	AQI	Range	PM2.5 avg	Hours	Stations
2026-07-22	28	18–42	6.6 µg/m³	6h	1
2026-07-21	41	38–42	9.8 µg/m³	3h	1
2026-07-20	74	57–93	23.0 µg/m³	6h	1
2026-07-19	133	95–187	62.3 µg/m³	4h	1
2026-07-18	90	38–178	40.5 µg/m³	4h	1
2026-07-17	311	310–312	263.1 µg/m³	2h	1
2026-07-14	60	57–62	16.4 µg/m³	3h	1
2026-07-13	59	51–65	15.8 µg/m³	7h	1
2026-07-12	63	57–70	17.6 µg/m³	7h	1
2026-07-11	30	22–38	7.3 µg/m³	13h	1
2026-07-10	32	18–47	7.6 µg/m³	15h	1
2026-07-09	47	38–53	11.2 µg/m³	13h	1
2026-07-08	45	30–59	11.1 µg/m³	10h	1

Back to Sarnia Air Quality