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 20 Jan 2024: Bohumín 28.3 µg/m³, Opava 25.4 µg/m³ and Havířov 24.8 µg/m³.
- 1BohumínMoravian-Silesian Region28.3
- 2OpavaMoravian-Silesian Region25.4
- 3HavířovMoravian-Silesian Region24.8
- 4DěčínÚstí nad Labem Region23.3
- 5Frýdek-MístekMoravian-Silesian Region23.2
- 6Moravská TřebováPardubice Region22.1
- 7Valašské MeziříčíZlín22.0
- 8PřerovOlomouc Region21.7
- 9TřinecMoravian-Silesian Region21.6
- 10OlomoucOlomouc Region21.5
- 11OstravaMoravian-Silesian Region21.2
- 12StudénkaMoravian-Silesian Region19.4
- 13ZlínZlín19.3
- 14Český TěšínMoravian-Silesian Region18.6
- 15KroměřížZlín18.0
- 16PardubicePardubice Region17.5
- 17ZnojmoSouth Moravian17.4
- 18MostÚstí nad Labem Region17.2
- 19Ústí nad LabemÚstí nad Labem Region16.1
- 20TepliceÚstí nad Labem Region16.1
+ 11 more cities, 16.1 µg/m³ and below
Not counted on this day, too few days measured: Beroun since 3 Jan 2024, České Budějovice since 31 Dec 2023 and Prague since 30 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 readers for them. Most cities there are missing from this board, not clean. Why.