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.
The worst cities in Canada for PM2.5 over the 30 days to 11 Sep 2025: Grande Prairie 27.1 µg/m³, Edmonton 25.8 µg/m³ and Fort Saskatchewan 23.7 µg/m³.
- 1Grande PrairieAlberta27.1
- 2EdmontonAlberta25.8
- 3Fort SaskatchewanAlberta23.7
- 4Prince GeorgeBritish Columbia22.9
- 5Fort McMurrayAlberta22.6
- 6St. AlbertAlberta20.9
- 7CalgaryAlberta20.3
- 8Fort St. JohnBritish Columbia20.0
- 9QuesnelBritish Columbia20.0
- 10Sherwood ParkAlberta20.0
- 11Williams LakeBritish Columbia19.0
- 12SquamishBritish Columbia18.9
- 13LethbridgeAlberta17.9
- 14EdsonAlberta17.7
- 15Red DeerAlberta17.5
- 16Drayton ValleyAlberta16.0
- 17Grand CentreAlberta15.5
- 18CastlegarBritish Columbia15.4
- 19HopeBritish Columbia15.0
- 20EstevanSaskatchewan14.0
+ 97 more cities, 13.8 µg/m³ and below
Not counted on this day, too few days measured: Flin Flon since 23 Aug 2025.
Cities counted each 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.