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.
The worst cities in Czechia for PM2.5 over the 30 days to 22 May 2024: Český Těšín 12.0 µg/m³, Havířov 11.8 µg/m³ and Ostrava 11.6 µg/m³.
- 1Český TěšínMoravian-Silesian Region12.0
- 2HavířovMoravian-Silesian Region11.8
- 3OstravaMoravian-Silesian Region11.6
- 4BohumínMoravian-Silesian Region11.2
- 5KladnoCentral Bohemia11.1
- 6Valašské MeziříčíZlín10.9
- 7StudénkaMoravian-Silesian Region10.8
- 8Frýdek-MístekMoravian-Silesian Region10.8
- 9DěčínÚstí nad Labem Region10.8
- 10TřinecMoravian-Silesian Region10.5
- 11OlomoucOlomouc Region10.3
- 12NáchodHradec Králové Region10.3
- 13OpavaMoravian-Silesian Region10.1
- 14PřerovOlomouc Region9.9
- 15PardubicePardubice Region9.6
- 16Hradec KrálovéHradec Králové Region9.6
- 17BerounCentral Bohemia9.6
- 18Moravská TřebováPardubice Region9.4
- 19PraguePrague9.2
- 20Mladá BoleslavCentral Bohemia9.1
+ 18 more cities, the next at 9.0 µg/m³
Cities counted each 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.