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 23 Jan 2024: Bohumín 28.7 µg/m³, Olomouc 26.0 µg/m³ and Beroun 25.7 µg/m³.
- 1BohumínMoravian-Silesian Region28.7
- 2OlomoucOlomouc Region26.0
- 3BerounCentral Bohemia25.7
- 4HavířovMoravian-Silesian Region25.6
- 5DěčínÚstí nad Labem Region25.1
- 6OpavaMoravian-Silesian Region24.9
- 7Moravská TřebováPardubice Region24.5
- 8PřerovOlomouc Region24.2
- 9Frýdek-MístekMoravian-Silesian Region23.7
- 10OstravaMoravian-Silesian Region22.7
- 11Valašské MeziříčíZlín22.5
- 12TřinecMoravian-Silesian Region21.2
- 13StudénkaMoravian-Silesian Region21.1
- 14ZlínZlín21.0
- 15ZnojmoSouth Moravian19.9
- 16Český TěšínMoravian-Silesian Region19.9
- 17MostÚstí nad Labem Region19.5
- 18TepliceÚstí nad Labem Region19.2
- 19KroměřížZlín18.9
- 20PraguePrague18.5
+ 13 more cities, the next at 18.2 µg/m³
Not counted on this day, too few days measured: České Budějovice since 31 Dec 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.