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 Sep 2023: Děčín 13.3 µg/m³, Český Těšín 13.3 µg/m³ and Kadaň 13.1 µg/m³.
- 1DěčínÚstí nad Labem Region13.3
- 2Český TěšínMoravian-Silesian Region13.3
- 3KadaňÚstí nad Labem Region13.1
- 4OstravaMoravian-Silesian Region12.9
- 5OlomoucOlomouc Region12.5
- 6HavířovMoravian-Silesian Region12.5
- 7MostÚstí nad Labem Region12.0
- 8Frýdek-MístekMoravian-Silesian Region11.7
- 9BohumínMoravian-Silesian Region11.6
- 10PardubicePardubice Region11.5
- 11OpavaMoravian-Silesian Region11.3
- 12PřerovOlomouc Region11.2
- 13KladnoCentral Bohemia11.2
- 14PraguePrague10.9
- 15LitvínovÚstí nad Labem Region10.9
- 16Hradec KrálovéHradec Králové Region10.9
- 17Valašské MeziříčíZlín10.8
- 18TřinecMoravian-Silesian Region10.8
- 19TepliceÚstí nad Labem Region10.7
- 20StudénkaMoravian-Silesian Region10.7
+ 15 more cities, the next at 10.4 µg/m³
Not counted on this day, too few days measured: Beroun since 15 Sep 2023.
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.