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 5 May 2026: San Antonio la Isla 31.7 µg/m³, San Salvador Tizatlalli 31.7 µg/m³ and San Luis Potosí 30.5 µg/m³.
- 1San Antonio la IslaMéxico31.7
- 2San Salvador TizatlalliMéxico31.7
- 3San Luis PotosíSan Luis Potosí30.5
- 4AguascalientesAguascalientes29.8
- 5XonacatlánMéxico29.4
- 6Hacienda Santa FeJalisco26.0
- 7TlaquepaqueJalisco25.2
- 8Naucalpan de JuárezMéxico24.2
- 9Victoria de DurangoDurango23.3
- 10Ciudad NezahualcoyotlMéxico22.5
- 11Atotonilco de TulaHidalgo22.0
- 12Silao de la VictoriaGuanajuato22.0
- 13PueblaPuebla21.9
- 14Zacatepec de HidalgoMorelos21.4
- 15CelayaGuanajuato21.4
- 16MoreliaMichoacán21.3
- 17YecapixtlaMorelos20.0
- 18Tetela del VolcánMorelos20.0
- 19Mexico CityMexico City19.7
- 20Mixquiahuala de JuárezHidalgo19.3
+ 31 more cities, 19.3 µg/m³ and below
Not counted on this day, too few days measured: Tuxtla since 5 May 2026, Ciudad General Escobedo since 29 Apr 2026, San Francisco Tlalcilalcalpan since 21 Apr 2026 and 4 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.