Add another weather-related advisory to the list this week for Southern California.
An ozone advisory was issued for the region ahead of excessive heat watches and warnings that are set to go into effect this week and continue through the weekend.
Here's what the ozone advisory issued by the South Coast Air Quality Management District means for Southern Californians.
Map: Check air quality near you
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What is an ozone advisory?
An ozone advisory is issued by the South Coast AQMD when ozone air pollution is expected to reach unhealthy levels. Extreme temperatures increase emissions of chemicals that lead to the formation of ozone. During an extended heat wave like the one bearing down on the region this week and continuing into the weekend, levels of ground-level ozone, aka smog, are likely to be unusually high.
When and where is the ozone advisory in effect?
The ozone advisory will be in effect from 11 a.m. Tuesday to Sunday. Unhealthy for Sensitive Groups and Unhealthy Air Quality Index (AQI) levels are likely in inland areas of the South Coast Air Basin most afternoons. Air quality will likely be even worse in the San Bernardino Mountains and San Bernardino Valley with Very Unhealthy AQI levels possible in the afternoon.
The ozone advisory comes as extreme heat watches and warnings are issued for a widespread part of Southern California, beginning Tuesday and continuing through the weekend. Triple-digit heat is in the forecast for valleys and inland areas.
The AQMD said poor air quality is possible over the coming week in the following areas.
- Central Los Angeles
- Southeastern LA County
- San Fernando Valley
- San Gabriel Valley
- Santa Clarita Valley
- San Gabriel Mountains
- South-Central Los Angeles County
- Pomona-Walnut Valley area
- Northern and central Orange County
- Saddleback Valley
- Corona-Norco area
- Metropolitan Riverside County
- Perris Valley
- Lake Elsinore
- Temecula Valley
- Anza Valley
- Hemet-San Jacinto Valley
- San Gorgonio Pass
- Coachella Valley
- San Bernardino Valley
- San Bernardino County mountains
What are the dangers of ozone air pollution?
Ozone air pollution can cause respiratory problems, including trouble breathing, asthma attacks, and lung damage. Children, older adults and people with asthma or other respiratory conditions might be more sensitive to the effects of elevated ozone levels.
How is the air quality near me?
You can check the South Coast air quality map or click here for current air quality conditions by region. You also can sign up for air quality updates and notifications from the South Coast AQMD app.