LAS VEGAS >> Air quality officials in Las Vegas have issued a health alert for people who may be sensitive to ozone pollution.
The Clark County Department of Air Quality said ozone pollution levels reached unhealthy levels Monday for people with respiratory problems or cardiac disease, young children and senior citizens.
A forecast says ozone levels were expected to be high during afternoon hours until Thursday. That means the alert may be extended.
County officials say the apparent cause of the ozone layer is a high-pressure weather system with airflow from Southern California, and little wind and high temperatures in the Las Vegas valley.