SmogRank / History / City race

Cities in United States, 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 to16 Sep 2024 That day's board

The worst cities in United States for PM2.5 over the 30 days to 16 Sep 2024: Meridian 24.0 µg/m³, Garden City 21.6 µg/m³ and Big Bear City 20.2 µg/m³.

  1. 1MeridianIdaho24.0
  2. 2Garden CityIdaho21.6
  3. 3Big Bear CityCalifornia20.2
  4. 4NampaIdaho19.8
  5. 5WeiserIdaho19.6
  6. 6Twin FallsIdaho19.4
  7. 7FontanaCalifornia18.8
  8. 8Jurupa ValleyCalifornia17.1
  9. 9HelenaMontana16.7
  10. 10Helena Valley West CentralMontana16.7
  11. 11BendOregon16.4
  12. 12RiversideCalifornia16.3
  13. 13ButteMontana16.1
  14. 14PrinevilleOregon15.7
  15. 15MiamiOklahoma15.6
  16. 16ColumbiaMissouri15.4
  17. 17GlendoraCalifornia14.6
  18. 18RedmondOregon14.3
  19. 19Port IsabelTexas14.0
  20. 20BirminghamAlabama13.8

+ 793 more cities, 13.7 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.