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 26 Aug 2023: Děčín 12.8 µg/m³, Český Těšín 12.3 µg/m³ and Havířov 12.1 µg/m³.
- 1DěčínÚstí nad Labem Region12.8
- 2Český TěšínMoravian-Silesian Region12.3
- 3HavířovMoravian-Silesian Region12.1
- 4StudénkaMoravian-Silesian Region11.7
- 5OstravaMoravian-Silesian Region11.6
- 6LitvínovÚstí nad Labem Region11.6
- 7KadaňÚstí nad Labem Region11.6
- 8OlomoucOlomouc Region11.5
- 9Frýdek-MístekMoravian-Silesian Region11.5
- 10Valašské MeziříčíZlín11.2
- 11BohumínMoravian-Silesian Region11.2
- 12Hradec KrálovéHradec Králové Region11.0
- 13TepliceÚstí nad Labem Region10.8
- 14PřerovOlomouc Region10.7
- 15Moravská TřebováPardubice Region10.7
- 16TřinecMoravian-Silesian Region10.6
- 17ZlínZlín10.3
- 18ŽideniceSouth Moravian9.8
- 19SlatinaSouth Moravian9.8
- 20ZnojmoSouth Moravian9.7
+ 9 more cities, the next at 9.7 µg/m³
Not counted on this day, too few days measured: Most since 26 Aug 2023, Prague since 7 Aug 2023, Rokycany since 31 Jul 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.