SmogRank / History / City race

Cities in Czechia, 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 to26 Mar 2023 That day's board

The worst cities in Czechia for PM2.5 over the 30 days to 26 Mar 2023: Bohumín 22.4 µg/m³, Frýdek-Místek 19.6 µg/m³ and Havířov 19.2 µg/m³.

  1. 1BohumínMoravian-Silesian Region22.4
  2. 2Frýdek-MístekMoravian-Silesian Region19.6
  3. 3HavířovMoravian-Silesian Region19.2
  4. 4Valašské MeziříčíZlín18.9
  5. 5KarvináMoravian-Silesian Region18.8
  6. 6TřinecMoravian-Silesian Region18.1
  7. 7DěčínÚstí nad Labem Region18.1
  8. 8OstravaMoravian-Silesian Region17.9
  9. 9Český TěšínMoravian-Silesian Region17.5
  10. 10OpavaMoravian-Silesian Region17.3
  11. 11PřerovOlomouc Region16.8
  12. 12HraniceOlomouc Region16.2
  13. 13HodonínSouth Moravian15.5
  14. 14ZlínZlín15.3
  15. 15OlomoucOlomouc Region15.3
  16. 16BerounCentral Bohemia15.2
  17. 17JihlavaVysocina14.2
  18. 18ZnojmoSouth Moravian14.1
  19. 19KroměřížZlín13.9
  20. 20ŽideniceSouth Moravian13.8

+ 16 more cities, 13.6 µg/m³ and below

Not counted on this day, too few days measured: Slatina since 31 Jan 2023. Days missing from the source archive fall in this window, so fewer countries are counted.

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.