Lingering smoke from wildland fires in Northern California, combined with a one-day heat wave in the forecast has resulted in a Spare the Air alert for the Bay Area on Tuesday.

The alert is the third issued for the region this year by the Bay Area Air Quality Management District.

Smoke from the Six Rivers Lightning Complex Fire in Humboldt and Trinity counties continues to impact the area, officials said. The wildfire started on Aug. 5, has burned 19,272 acres and is 17% contained as of Tuesday, according to CalFire.

A heat advisory issued by the National Weather Service is in effect from 11 a.m. to 8 p.m. Tuesday, when some locations will see temperatures in the triple digits.

"High temperatures, wildfire smoke and tailpipe exhaust are expected to impact our air quality on Tuesday," said Veronica Eady, senior deputy executive officer of policy and equity at the air district.

Air quality readings are available at baaqmd.gov/highs.

The air alerts are issued when ozone pollution, or smog, is forecast to be unhealthy. Ozone can cause throat irritation, congestion and chest pain. It can also trigger asthma, inflame the lining of the lungs and worsen bronchitis and emphysema, air district officials said.

Long-term exposure can reduce lung function and ozone pollution. Ozone pollution is particularly harmful for young children, seniors and those with respiratory and heart conditions.

During a Spare the Air day, outdoor exercise should be limited to early morning hours when ozone concentrations are lower, air district officials said.