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 18 Mar 2024: Náchod 25.3 µg/m³, Ostrava 22.6 µg/m³ and Bohumín 22.0 µg/m³.
- 1NáchodHradec Králové Region25.3
- 2OstravaMoravian-Silesian Region22.6
- 3BohumínMoravian-Silesian Region22.0
- 4DěčínÚstí nad Labem Region21.0
- 5OpavaMoravian-Silesian Region20.7
- 6HavířovMoravian-Silesian Region20.7
- 7Český TěšínMoravian-Silesian Region20.1
- 8Ústí nad LabemÚstí nad Labem Region19.4
- 9LitvínovÚstí nad Labem Region19.3
- 10BerounCentral Bohemia19.3
- 11Moravská TřebováPardubice Region19.2
- 12Valašské MeziříčíZlín18.7
- 13StudénkaMoravian-Silesian Region18.7
- 14Hradec KrálovéHradec Králové Region18.4
- 15TepliceÚstí nad Labem Region18.3
- 16Frýdek-MístekMoravian-Silesian Region18.3
- 17PilsenPlzeň Region17.7
- 18ZnojmoSouth Moravian17.3
- 19TřinecMoravian-Silesian Region17.3
- 20KadaňÚstí nad Labem Region17.3
+ 14 more cities, 16.9 µg/m³ and below
Not counted on this day, too few days measured: Židenice since 18 Mar 2024, Slatina since 18 Mar 2024, Most since 17 Mar 2024 and Kladno since 17 Mar 2024.
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.