SmogRank / History / City race

Cities, 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 7 days to24 Aug 2023 That day's board

The worst cities for PM2.5 over the 7 days to 24 Aug 2023: Kamloops 140.9 µg/m³, Kelowna 108.5 µg/m³ and Penticton 104.2 µg/m³.

  1. 1KamloopsCanada140.9
  2. 2KelownaCanada108.5
  3. 3PentictonCanada104.2
  4. 4RedmondUnited States99.3
  5. 5CheneyUnited States87.2
  6. 6MeadUnited States86.1
  7. 7EphrataUnited States85.4
  8. 8SpokaneUnited States84.9
  9. 9VernonCanada83.5
  10. 10AshlandUnited States81.5
  11. 11Moses LakeUnited States79.5
  12. 12Tri-CitiesUnited States79.3
  13. 13Walla WallaUnited States79.1
  14. 14Spokane ValleyUnited States74.6
  15. 15HermistonUnited States73.5
  16. 16ManamaBahrain70.1
  17. 17MedfordUnited States70.0
  18. 18Airway HeightsUnited States69.7
  19. 19CastlegarCanada68.8
  20. 20CoyhaiqueChile68.2

+ 1,974 more cities, 67.2 µg/m³ and below

Not counted on this day, too few days measured: Ceglie Messapica since 28 Jul 2023, Laja since 27 Jul 2023 and Hualpén since 26 Jul 2023.

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.