SmogRank / History / City race
Cities in Mexico, 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 Mexico for PM2.5 over the 30 days to 11 Oct 2025: Xonacatlán 23.9 µg/m³, Cholula 23.0 µg/m³ and San Antonio la Isla 20.0 µg/m³.
- 1XonacatlánMéxico23.9
- 2CholulaPuebla23.0
- 3San Antonio la IslaMéxico20.0
- 4San Salvador TizatlalliMéxico20.0
- 5Santa CatarinaNuevo León19.5
- 6SaltilloCoahuila17.7
- 7Atotonilco de TulaHidalgo16.3
- 8TijuanaBaja California16.3
- 9GarcíaNuevo León15.4
- 10CuernavacaMorelos15.3
- 11Naucalpan de JuárezMéxico14.5
- 12NogalesSonora13.7
- 13Ciudad Benito JuárezNuevo León13.4
- 14Hacienda Santa FeJalisco12.9
- 15Mexico CityMexico City12.1
- 16PueblaPuebla12.0
- 17Cadereyta JiménezNuevo León11.7
- 18La PazBaja California Sur11.7
- 19TlaquepaqueJalisco11.3
- 20ZapopanJalisco11.2
+ 28 more cities, 11.2 µg/m³ and below
Not counted on this day, too few days measured: San Martin Texmelucan de Labastida since 5 Oct 2025, Mexicali since 26 Sep 2025, Tuxtla since 15 Sep 2025 and 5 more cities.
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.