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 28 May 2023: Havířov 15.6 µg/m³, Český Těšín 14.9 µg/m³ and Děčín 14.6 µg/m³.
- 1HavířovMoravian-Silesian Region15.6
- 2Český TěšínMoravian-Silesian Region14.9
- 3DěčínÚstí nad Labem Region14.6
- 4Frýdek-MístekMoravian-Silesian Region14.3
- 5OstravaMoravian-Silesian Region14.1
- 6OpavaMoravian-Silesian Region13.5
- 7BohumínMoravian-Silesian Region13.3
- 8BerounCentral Bohemia13.2
- 9KladnoCentral Bohemia13.1
- 10StudénkaMoravian-Silesian Region12.5
- 11LiberecLiberec Region12.4
- 12KadaňÚstí nad Labem Region12.3
- 13TřinecMoravian-Silesian Region12.2
- 14PřerovOlomouc Region12.0
- 15Valašské MeziříčíZlín11.9
- 16MostÚstí nad Labem Region11.9
- 17OlomoucOlomouc Region11.8
- 18Hradec KrálovéHradec Králové Region11.8
- 19PraguePrague11.5
- 20Moravská TřebováPardubice Region11.4
+ 14 more cities, the next at 11.3 µg/m³
Not counted on this day, too few days measured: Zlín since 16 May 2023, Žďár nad Sázavou since 30 Mar 2023, Kroměříž since 30 Mar 2023 and 4 more cities.
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.