SmogRank / History / City race
Cities in Portugal, 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 Portugal for PM2.5 over the 30 days to 6 Sep 2026: Porto 14.6 µg/m³, Vila Real 4.5 µg/m³ and Funchal 3.8 µg/m³.
- 1PortoPorto14.6
- 2Vila RealVila Real4.5
- 3FunchalMadeira3.8
- 4SantanaMadeira3.7
- 5ParedesPorto3.5
- 6FreamundePorto3.5
Not counted on this day, too few days measured: Santiago do Cacém since 22 Aug 2026, Sines since 13 Aug 2026 and Faro since 26 Jul 2026.
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.