A Spare the Air alert for smog has been issued for Sunday, officials with the Bay Area Air Quality Management District said.
Offshore winds in the morning, switching to light onshore winds in the afternoon, are expected to create unhealthy ozone levels in parts of the East Bay and Santa Clara Valley, air district officials said.
"Hot temperatures and traffic exhaust are expected to cause hazy skies and unhealthy air quality in the Bay Area this weekend," Jack Broadbent, executive officer of the Air District, said in a statement. "To reduce air pollution, try carpooling or taking transit to get around this weekend instead of driving alone."
This is the third Spare the Air alert for smog in 2017.
Spare the Air Alerts are called when ozone pollution is forecast to reach unhealthy levels. Ozone, or smog, can cause throat irritation, congestion and chest pain, trigger asthma, inflame the lining of the lungs and worsen bronchitis and emphysema.
Ozone pollution is particularly harmful for young children, seniors and those with respiratory and heart conditions, the air district said.
