LOS ANGELES - A heat wave ozone advisory and two smoke advisories remained in place Saturday due to air quality that could be unhealthy for residents with health issues.
The South Coast Air Quality Management District's heat wave ozone advisory was in effect through Monday afternoon and smoke advisories due to the Lake Fire and the Ranch2 Fire remained through Sunday afternoon.
"The heat wave, along with stagnant weather and ongoing wildfires will result in poor air quality for many parts of the region this weekend," the AQMD explained in a statement.
Air Quality Index levels of Unhealthy or Very Unhealthy are possible in areas not impacted by smoke, but due to elevated ozone concentrations --smog, the agency said.
Exposure to high levels of ozone can cause respiratory problems including trouble breathing, asthma attacks and lung damage, the agency said.
"Research also indicates that ozone exposure can increase the risk of premature death," the AQMD said. "Children, older adults and people with asthma or COPD may be more sensitive to the health effects of ozone."
Meteorological conditions could bring smoke and ash from the Ranch2 Fire north of Azusa into parts of Los Angeles and San Bernardino counties, making the air unhealthy or very unhealthy for sensitive groups.
Weather conditions could bring smoke and ash from the Lake Fire northeast of Castaic into parts of the San Gabriel Mountains and Santa Clarita Valley, making air unhealthy or very unhealthy for those sensitive groups.
People who smell smoke or see ash are urged to remain indoors with windows and doors closed and avoid vigorous physical activity.
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