SmogRank / History / City race

Cities in Canada, worst air first, day by day

Each measured city's average over the 30 days to every day since January 2023, worst first. Find your own city to follow it through the race, or keep to one country.

CountriesCities
The 30 days to13 Jul 2025 That day's board

The worst cities in Canada for PM2.5 over the 30 days to 13 Jul 2025: Flin Flon 21.6 µg/m³, Prince Albert 21.3 µg/m³ and Estevan 16.2 µg/m³.

  1. 1Flin FlonManitoba21.6
  2. 2Prince AlbertSaskatchewan21.3
  3. 3EstevanSaskatchewan16.2
  4. 4NepeanOntario13.9
  5. 5Fort McMurrayAlberta12.5
  6. 6ReginaSaskatchewan12.4
  7. 7WindsorOntario11.3
  8. 8NewmarketOntario10.2
  9. 9TorontoOntario10.1
  10. 10SaskatoonSaskatchewan10.0
  11. 11EdmontonAlberta9.9
  12. 12MiltonOntario9.9
  13. 13Grand CentreAlberta9.9
  14. 14Sault Ste. MarieOntario9.8
  15. 15BarrieOntario9.5
  16. 16SarniaOntario9.4
  17. 17BramptonOntario9.0
  18. 18Greater SudburyOntario9.0
  19. 19LondonOntario9.0
  20. 20Parry SoundOntario9.0

+ 97 more cities, 9.0 µg/m³ and below

30 days7 days
GoodModerateSensitive groupsUnhealthyVery unhealthyHazardousWHO 24-hour guideline, 15 µg/m³Fades where it stood: not counted that day

A city's number is its average over the 30 days, shown only when 21 of them were measured (5 of 7 on the 7-day race), the same minimum as the 30- and 7-day boards. A city whose monitors go quiet fades out where it stood rather than sliding down, so a gap never reads as cleaner air. Some large countries are thin or missing because their monitors' licences don't allow reuse. How we rank.

Not covered: the government monitoring networks of China and Turkey, which publish only on their own websites; we are building the readers for them. Most cities there are missing from this board, not clean. Why.