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 to17 May 2024 That day's board

The worst cities in Czechia for PM2.5 over the 30 days to 17 May 2024: Český Těšín 12.0 µg/m³, Havířov 11.8 µg/m³ and Ostrava 11.5 µg/m³.

  1. 1Český TěšínMoravian-Silesian Region12.0
  2. 2HavířovMoravian-Silesian Region11.8
  3. 3OstravaMoravian-Silesian Region11.5
  4. 4BohumínMoravian-Silesian Region11.4
  5. 5DěčínÚstí nad Labem Region11.3
  6. 6NáchodHradec Králové Region11.2
  7. 7KladnoCentral Bohemia11.1
  8. 8TřinecMoravian-Silesian Region10.9
  9. 9Frýdek-MístekMoravian-Silesian Region10.9
  10. 10Valašské MeziříčíZlín10.8
  11. 11StudénkaMoravian-Silesian Region10.6
  12. 12OlomoucOlomouc Region10.2
  13. 13OpavaMoravian-Silesian Region10.0
  14. 14BerounCentral Bohemia9.9
  15. 15PřerovOlomouc Region9.8
  16. 16PardubicePardubice Region9.7
  17. 17Moravská TřebováPardubice Region9.7
  18. 18PraguePrague9.5
  19. 19Hradec KrálovéHradec Králové Region9.1
  20. 20ZlínZlín9.0

+ 18 more cities, 8.8 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.