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 6 Oct 2026: Tuxtla 27.6 µg/m³, Mexicali 23.8 µg/m³ and Hacienda Santa Fe 23.6 µg/m³.
- 1TuxtlaChiapas27.6
- 2MexicaliBaja California23.8
- 3Hacienda Santa FeJalisco23.6
- 4TijuanaBaja California22.8
- 5SaltilloCoahuila18.1
- 6Santa AnitaJalisco17.2
- 7Ciudad NezahualcoyotlMéxico16.9
- 8Naucalpan de JuárezMéxico16.5
- 9GuadalajaraJalisco16.5
- 10AguascalientesAguascalientes16.2
- 11TlaquepaqueJalisco15.2
- 12PueblaPuebla15.0
- 13Mexico CityMexico City14.0
- 14Atotonilco de TulaHidalgo13.8
- 15Ciudad General EscobedoNuevo León12.3
- 16Ciudad ApodacaNuevo León12.3
- 17Parque Industrial Ciudad MitrasNuevo León12.3
- 18SalamancaGuanajuato11.9
- 19IrapuatoGuanajuato11.8
- 20León de los AldamaGuanajuato11.7
+ 22 more cities, 11.5 µg/m³ and below
Not counted on this day, too few days measured: Heroica Matamoros since 6 Oct 2026, San Antonio la Isla since 4 Oct 2026, San Salvador Tizatlalli since 4 Oct 2026 and 9 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.