LOS ANGELES (KABC) -- Southern California is expecting a late-summer heat wave this week and that is likely to cause unhealthy air quality in many parts of the region.
The South Coast Air Quality Management District has issued an Ozone Advisory starting Tuesday, indicating that inland communities can expect poor air quality. The worst air will be in parts of the San Bernardino Mountains and San Bernardino Valley in the afternoon hours.
The advisory is in effect from Tuesday Aug. 30 through Sunday, Sept. 4.
Higher temperatures lead to more emissions of dangerous chemicals that cause ozone formation, the agency says.
"This long duration and intense heat wave will likely cause unusually high and persistent levels of ozone pollution," the agency says.
The ozone pollution can be especially dangerous to vulnerable populations - children, older adults and people with respiratory issues such as asthma.
A list of communities that are most at risk can be found at the AQMD statement here.
The National Weather Service has issued an Excessive Heat Warning for parts of Southern California starting Wednesday morning through Monday evening.
The hottest temperatures are coming to inland valleys and deserts.
People are advised to drink plenty of fluids, stay indoors in air-conditioned locations and check on relatives and neighbors who may be vulnerable.