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 to15 Dec 2024 That day's board

The worst cities in Czechia for PM2.5 over the 30 days to 15 Dec 2024: Olomouc 15.8 µg/m³, Náchod 15.6 µg/m³ and Havířov 14.6 µg/m³.

  1. 1OlomoucOlomouc Region15.8
  2. 2NáchodHradec Králové Region15.6
  3. 3HavířovMoravian-Silesian Region14.6
  4. 4PřerovOlomouc Region14.5
  5. 5OstravaMoravian-Silesian Region14.3
  6. 6Moravská TřebováPardubice Region14.3
  7. 7StudénkaMoravian-Silesian Region14.1
  8. 8ZnojmoSouth Moravian13.7
  9. 9DěčínÚstí nad Labem Region13.4
  10. 10BohumínMoravian-Silesian Region13.0
  11. 11BrnoSouth Moravian12.8
  12. 12TepliceÚstí nad Labem Region12.6
  13. 13BerounCentral Bohemia12.5
  14. 14LitvínovÚstí nad Labem Region12.3
  15. 15ZlínZlín11.9
  16. 16Hradec KrálovéHradec Králové Region11.9
  17. 17Valašské MeziříčíZlín11.8
  18. 18Frýdek-MístekMoravian-Silesian Region11.7
  19. 19Český TěšínMoravian-Silesian Region11.3
  20. 20TřinecMoravian-Silesian Region11.1

+ 16 more cities, 11.0 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.