SmogRank / World / Mexico / March 2025

Most unhealthy days in Mexico, March 2025

23 cities in Mexico ranked by their share of unhealthy days over the 31 days. The most unhealthy days: Toluca, Mexico, 17 of 23 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.

← Toluca 74% 70%0
Every city in Mexico ranked for March 2025, 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. 1TolucaMéxico
    17 of 23
  2. 2San Antonio la IslaMéxico
    9 of 23
  3. 3Ciudad JuárezChihuahua
    5 of 23
  4. 4Ciudad NezahualcoyotlMéxico
    5 of 23
  5. 5XonacatlánMéxico
    5 of 25
  6. 6San Luis de la PazGuanajuato
    4 of 30
  7. 7MexicaliBaja California
    2 of 23
  8. 8HuichapanHidalgo
    2 of 23
  9. 9Heroica MatamorosTamaulipas
    2 of 31
  10. 10Mixquiahuala de JuárezHidalgo
    1 of 23
  11. 11Mexico CityMexico City
    1 of 24
  12. 12GuanajuatoGuanajuato
    1 of 27
  13. 13CelayaGuanajuato
    1 of 30
  14. 14IrapuatoGuanajuato
    1 of 31
  15. 15TehuacánPuebla
    0 of 22
  16. 16TlaxcalaTlaxcala
    0 of 22
  17. 17León de los AldamaGuanajuato
    0 of 31
  18. 18SalamancaGuanajuato
    0 of 29
  19. 19San Miguel de AllendeGuanajuato
    0 of 31
  20. 20TepicNayarit
    0 of 23
  21. 21AbasoloGuanajuato
    0 of 31
  22. 22TijuanaBaja California
    0 of 22
  23. 23ChihuahuaChihuahua
    0 of 23
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, March 2025 · Mexico now

Regions

Baja California 2Chihuahua 2Guanajuato 8Hidalgo 2México 4Mexico City 1Nayarit 1Puebla 1Tamaulipas 1

Ranked cities in each region, March 2025.

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SmogRank, most polluted cities in Mexico, by unhealthy days, PM2.5, March 2025, smogrank.com/mx/history/2025-03?by=days (accessed 7 Oct 2026).

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