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 25 May 2023: Havířov 15.3 µg/m³, Děčín 15.2 µg/m³ and Český Těšín 14.6 µg/m³.
- 1HavířovMoravian-Silesian Region15.3
- 2DěčínÚstí nad Labem Region15.2
- 3Český TěšínMoravian-Silesian Region14.6
- 4BohumínMoravian-Silesian Region14.2
- 5OstravaMoravian-Silesian Region13.9
- 6Frýdek-MístekMoravian-Silesian Region13.9
- 7BerounCentral Bohemia13.5
- 8KladnoCentral Bohemia13.4
- 9KadaňÚstí nad Labem Region12.8
- 10LiberecLiberec Region12.6
- 11Hradec KrálovéHradec Králové Region12.5
- 12StudénkaMoravian-Silesian Region12.3
- 13OlomoucOlomouc Region12.3
- 14MostÚstí nad Labem Region12.3
- 15Moravská TřebováPardubice Region11.9
- 16Valašské MeziříčíZlín11.8
- 17PraguePrague11.5
- 18ZnojmoSouth Moravian11.4
- 19Mladá BoleslavCentral Bohemia11.4
- 20LitvínovÚstí nad Labem Region11.2
+ 9 more cities, 10.9 µg/m³ and below
Not counted on this day, too few days measured: Zlín since 16 May 2023, Žďár nad Sázavou since 30 Mar 2023, Třinec since 30 Mar 2023 and 9 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 readers for them. Most cities there are missing from this board, not clean. Why.