SmogRank / World / Mexico / Baja California / 2025

Most unhealthy days in Baja California, Mexico, 2025

2 cities in Baja California, Mexico ranked by their share of unhealthy days over the 365 days. The most unhealthy days: Mexicali, Mexico, 35 of 284 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.

  1. 1Mexicali
    35 of 284
  2. 2Tijuana
    40 of 347
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

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SmogRank, most polluted cities in Baja California, Mexico, by unhealthy days, PM2.5, 2025, smogrank.com/mx/region/baja-california/history/2025?by=days (accessed 8 Oct 2026).

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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.