Is the air quality good in Los Angeles?
On December 13, 2025, at 1:30 AM PT, Los Angeles, California, is experiencing poor air quality, with an Air Quality Index (AQI) of 102 classified as “unhealthy for sensitive groups“.
An air quality alert is in effect across much of the region due to elevated fine particulate pollution, prompting a mandatory wood-burning ban in the South Coast Air Basin (1).
Air quality is dynamic and, like the weather, can change frequently. Los Angeles ranks 16th among the most polluted cities in the world on Saturday morning.
Click here for a real-time air quality map of Los Angeles.
While the air quality conditions today are unusually poor, it is important to keep in mind that the average PM2.5 concentration in 2024 for Los Angeles was 10 µg/m3. This corresponds to an AQI of 42, which falls into the “good” category and was 2 times the WHO annual guideline of 5 µg/m3.
Los Angeles, California was ranked as 16th most polluted major city on Dec 13, 2025, 1:30 AM PT. Source: IQAir.
When will air quality improve in Los Angeles?
Air quality in Los Angeles is forecasted to improve later today as weather conditions become more favorable for pollutant dispersion (2).
Hourly air quality forecast for Los Angeles, California for Dec 13, 2025. Source: IQAir.
Air quality Map of Los Angeles, California on Dec 13, 2025. Source: IQAir.
What is causing poor air quality in Los Angeles?
Poor air quality in Los Angeles is being driven by a combination of seasonal, geographic, and human-related factors. Wintertime stagnant air conditions are allowing fine particulate matter to build up near the ground.
The primary factors contributing to the current poor air quality include:
- Residential wood burning contributing to fine particle pollution, leading to a No-Burn Day declaration (3)
- High vehicle emissions producing nitrogen oxides and volatile organic compounds that form photo-chemical smog
- Geographic basin surrounded by mountains that traps pollutants
- Temperature inversions that prevent vertical air mixing
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