SmogRank / World / Mexico / October 2023

Most unhealthy days in Mexico, October 2023

11 cities in Mexico ranked by their share of unhealthy days over the 31 days. The most unhealthy days: Tijuana, Mexico, 1 of 31 measured days. A city needs measurements on 70% of the days to be ranked.

Ranked by unhealthy days: the share of each city's measured days with a daily mean over 35.4 µg/m³ (US AQI 101+), Unhealthy for Sensitive Groups or worse on the US EPA's scale. Ties go to the higher average.

← Tijuana 3% 3%0
Every city in Mexico ranked for October 2023, one column each, ranked by unhealthy days: height is the share of its measured days that were unhealthy, colour its average. Point at it to read a city; tap to open it.
  1. 1TijuanaBaja California
    1 of 31
  2. 2SalamancaGuanajuato
    0 of 29
  3. 3CelayaGuanajuato
    0 of 30
  4. 4NogalesSonora
    0 of 30
  5. 5Silao de la VictoriaGuanajuato
    0 of 26
  6. 6León de los AldamaGuanajuato
    0 of 30
  7. 7IrapuatoGuanajuato
    0 of 31
  8. 8San Luis de la PazGuanajuato
    0 of 30
  9. 9Ciudad JuárezChihuahua
    0 of 31
  10. 10GuanajuatoGuanajuato
    0 of 27
  11. 11AbasoloGuanajuato
    0 of 29
Good0–50
Moderate51–100
Sensitive groups101–150
Unhealthy151–200
Very unhealthy201–300
Hazardous301+

The US EPA's Air Quality Index for PM2.5 (2024 breakpoints). Show values as: µg/m³ · US AQI · India AQI · China AQI · European AQI · UK DAQI · Canada AQHI+. About the scales

All cities in the world, October 2023 · Mexico now

Regions

Baja California 1Chihuahua 1Guanajuato 8Sonora 1

Ranked cities in each region, October 2023.

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SmogRank, most polluted cities in Mexico, by unhealthy days, PM2.5, October 2023, smogrank.com/mx/history/2023-10?by=days (accessed 7 Oct 2026).

Download top 10 by average (PNG)

You're welcome to reuse a single chart, image or figure with this citation and a link. Terms. Raw monitor readings in bulk are published by OpenAQ, under each provider's licence.