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 21 Dec 2023: Bohumín 29.1 µg/m³, Havířov 28.6 µg/m³ and Český Těšín 28.5 µg/m³.
- 1BohumínMoravian-Silesian Region29.1
- 2HavířovMoravian-Silesian Region28.6
- 3Český TěšínMoravian-Silesian Region28.5
- 4OstravaMoravian-Silesian Region27.2
- 5Frýdek-MístekMoravian-Silesian Region26.4
- 6StudénkaMoravian-Silesian Region25.6
- 7Moravská TřebováPardubice Region24.2
- 8Valašské MeziříčíZlín23.6
- 9DěčínÚstí nad Labem Region23.6
- 10PřerovOlomouc Region23.4
- 11OpavaMoravian-Silesian Region23.4
- 12TřinecMoravian-Silesian Region22.8
- 13OlomoucOlomouc Region22.4
- 14BerounCentral Bohemia20.0
- 15TepliceÚstí nad Labem Region19.8
- 16ŽideniceSouth Moravian19.2
- 17SlatinaSouth Moravian19.2
- 18MostÚstí nad Labem Region19.2
- 19ZlínZlín19.0
- 20LitvínovÚstí nad Labem Region18.9
+ 14 more cities, 18.9 µg/m³ and below
Not counted on this day, too few days measured: Rokycany since 13 Nov 2023 and Kladno since 25 Oct 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.