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 7 Oct 2025: Cholula 25.1 µg/m³, Xonacatlán 24.7 µg/m³ and San Antonio la Isla 21.0 µg/m³.
- 1CholulaPuebla25.1
- 2XonacatlánMéxico24.7
- 3San Antonio la IslaMéxico21.0
- 4San Salvador TizatlalliMéxico21.0
- 5Santa CatarinaNuevo León19.8
- 6CuernavacaMorelos16.7
- 7TijuanaBaja California16.6
- 8Atotonilco de TulaHidalgo16.5
- 9GarcíaNuevo León15.3
- 10Naucalpan de JuárezMéxico15.0
- 11Hacienda Santa FeJalisco13.7
- 12NogalesSonora13.3
- 13Ciudad Benito JuárezNuevo León13.0
- 14La PazBaja California Sur12.9
- 15PueblaPuebla12.8
- 16Mexico CityMexico City12.6
- 17MoreliaMichoacán12.2
- 18ZapopanJalisco11.9
- 19San Luis de la PazGuanajuato11.9
- 20San MarcosHidalgo11.8
+ 25 more cities, 11.7 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 7 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.