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 to20 Aug 2024 That day's board

The worst cities in United States for PM2.5 over the 30 days to 20 Aug 2024: Meridian 28.8 µg/m³, Nampa 27.8 µg/m³ and Garden City 27.3 µg/m³.

  1. 1MeridianIdaho28.8
  2. 2NampaIdaho27.8
  3. 3Garden CityIdaho27.3
  4. 4AltamontOregon25.7
  5. 5WeiserIdaho24.2
  6. 6BendOregon24.0
  7. 7LewistonIdaho21.9
  8. 8Baker CityOregon20.6
  9. 9RedmondOregon20.1
  10. 10Twin FallsIdaho19.6
  11. 11ToppenishWashington19.2
  12. 12Great FallsMontana19.1
  13. 13MedfordOregon18.2
  14. 14Miles CityMontana16.9
  15. 15AshlandOregon16.9
  16. 16TalentOregon16.7
  17. 17La GrandeOregon16.6
  18. 18ColumbiaMissouri16.4
  19. 19PrinevilleOregon16.3
  20. 20HelenaMontana16.2

+ 779 more cities, the next at 16.2 µg/m³

Not counted on this day, too few days measured: Port Isabel since 13 Aug 2024.

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 reader for China's network. Turkey's network doesn't answer requests from outside the country, so we can't read it. Most cities there are missing from this board, not clean. Why.