Public health officials often recommend limiting time spent outside when AQI levels rise, especially for high-risk demographics. Air quality was so poor in parts of Southern California on Friday ...

That’s worse than the last two yearly reports, which Chicago ranked 17th. California dominated this year’s list, with 9 of the 25 most polluted cities. Los Angeles ranked first for most polluted by ...

After a decidedly weird and only occasionally wet winter, California is once again drying out — and fast. New data compiled by the National Oceanic and Atmospheric Administration shows that ...