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 10 Nov 2025: Cholula 38.2 µg/m³, Tijuana 30.9 µg/m³ and Xonacatlán 28.9 µg/m³.
- 1CholulaPuebla38.2
- 2TijuanaBaja California30.9
- 3XonacatlánMéxico28.9
- 4San Antonio la IslaMéxico28.6
- 5Hacienda Santa FeJalisco28.6
- 6San Salvador TizatlalliMéxico28.6
- 7TlaquepaqueJalisco25.2
- 8TuxtlaChiapas24.0
- 9Ciudad Benito JuárezNuevo León23.8
- 10SalamancaGuanajuato22.3
- 11GarcíaNuevo León22.2
- 12Santa CatarinaNuevo León20.4
- 13MexicaliBaja California19.4
- 14SaltilloCoahuila18.7
- 15Santa AnitaJalisco18.1
- 16MoreliaMichoacán18.1
- 17AguascalientesAguascalientes18.1
- 18Naucalpan de JuárezMéxico18.0
- 19Silao de la VictoriaGuanajuato18.0
- 20PueblaPuebla17.8
+ 25 more cities, 17.6 µg/m³ and below
Not counted on this day, too few days measured: San Francisco Tlalcilalcalpan since 10 Nov 2025, Santiaguito Tlalcilalcalli since 10 Nov 2025, Irapuato since 5 Nov 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.