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 15 Nov 2024: Náchod 25.4 µg/m³, Přerov 24.9 µg/m³ and Ústí nad Labem 24.1 µg/m³.
- 1NáchodHradec Králové Region25.4
- 2PřerovOlomouc Region24.9
- 3Ústí nad LabemÚstí nad Labem Region24.1
- 4OlomoucOlomouc Region23.9
- 5Hradec KrálovéHradec Králové Region23.7
- 6ZnojmoSouth Moravian22.0
- 7BerounCentral Bohemia21.4
- 8BrnoSouth Moravian20.1
- 9MostÚstí nad Labem Region19.5
- 10PilsenPlzeň Region19.3
- 11LitvínovÚstí nad Labem Region19.1
- 12PraguePrague18.5
- 13MikulovSouth Moravian17.7
- 14KladnoCentral Bohemia17.6
- 15České BudějoviceSouth Bohemian Region16.9
- 16RokycanyPlzeň Region15.9
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.