For the second straight day and the sixth time this year, a Spare the Air alert has been declared for Thursday in the Bay Area because of ongoing air pollution issues related to wildfire smoke and smog from vehicles.
The Bay Area Air Quality Management District issued the alert because of unhealthy levels of smoke and smog, otherwise known as ozone, that can cause breathing issues and other health problems.
The air district encourages people on Spare the Air days to only exercise outdoors in the early morning hours when ozone levels are lower, and to stay inside if possible with windows and doors closed until pollution levels subside.
Increased onshore winds are expected to improve air quality conditions starting Friday and through the weekend, according to the air district.
Smoke has drifted into the Bay Area from wildfires further north, including the Mendocino Complex Fire that has burned more than 300,000 acres, making it the largest fire in California history.
People can find out when a Spare the Air alert is in effect by registering for email alerts at www.sparetheair.org, calling 800-HELP-AIR, downloading the Spare the Air smartphone app or connecting with Spare the Air on social media.