Smog Advisory Issued Across The San Fernando Valley

LOS ANGELES, CA — The searing summer heat across Los Angeles County prompted the South Coast Air Quality Management District on Thursday to issue an Ozone Advisory in effect from 2 p.m. Friday through 8 p.m. Tuesday.

The "multi-day extreme ozone (smog) event" will see air quality likely reach "Unhealthy" or levels across the region, including the San Fernando, Santa Clarita and San Gabriel valleys, the SCAQMD announced. Air quality in those regions is expected to be unhealthy for sensitive groups including young children, the elderly and people who suffer from asthma.

"The persistently high ozone levels are in part caused by high temperatures that increase ozone formation rates and emissions of chemicals leading to ozone formation," according to the SCAQMD.

Temperatures will be highest over the weekend, with the mercury rising into the 100s across the valleys and mountains. The National Weather Service issued an Excessive Heat Warning for the region that is in effect through 8 p.m. Tuesday.

The poor air quality across the region is worrisome.

"Ozone air pollution can cause respiratory health problems, including trouble breathing, asthma attacks, and lung damage," according to the SCAQMD. "Research also indicates that ozone exposure can increase the risk of premature death. Children, older adults, pregnant people, and people with preexisting lung problems such as asthma may be more sensitive to the health effects of ozone."

When smog levels reach SCAQMD's "Unhealthy" level, "everyone may begin to experience some adverse health effects, and members of the sensitive groups may experience more serious effects. People with heart or lung disease, older adults, and children should avoid prolonged or heavy exertion. Everyone else should reduce prolonged or heavy exertion," according to the agency.

When levels reach the "Very Unhealthy" level, "everyone may experience more serious health effects," according to the agency. "People with heart or lung disease, older adults, and children should avoid all physical activity outdoors. Everyone else should avoid prolonged or heavy exertion."

Thursday's SCAQMD announcement falls on the heels of an advisory by the agency last week warning of high pollution due to July 4 fireworks.

The SCAQMD is the air pollution control agency for the South Coast Air basin. The basin includes California's largest metropolitan region, including the western portions of Riverside and San Bernardino Counties, the southern two-thirds of Los Angeles County, and all of Orange County.

To view current air quality in your neighborhood, download the South Coast AQMDapp or visit www.aqmd.gov/AQImap.