Millions of residents across parts of Southern California and Arizona are being warned to limit outdoor activity this weekend as ozone pollution—commonly known as smog—is expected to reach potentially unhealthy levels.
Air quality alerts issued by the National Weather Service (NWS) cover large parts of the Phoenix metro area and California’s Imperial Valley, where heat and stagnant air are expected to trap pollution close to the ground through Sunday evening.
Affected Areas
In California’s Imperial Valley, including cities like El Centro, Calexico, Alamorio, and Brawley, the NWS issued an air quality alert that began on Saturday and is set to remain in effect until Sunday night.
Meanwhile, in Arizona, the Phoenix metro area and wider Maricopa County are under an “Ozone High Pollution Advisory” through Sunday, according to the NWS…