A Spare the Air alert has been issued for Friday due to smoggy conditions caused by high temperatures, car exhaust and low winds, according to the region's air quality district.
Commuters are encouraged to take public transit or carpool instead of driving to work, and limit other activities that cause pollution such as using oil-based paints, gas-powered garden equipment, and aerosol sprays.
Stay indoors, too, asks the Bay Area Air Quality Management District. Not that you'll need much convincing -- it is going to be a scorcher. Triple-digit highs are expected for Livermore, Concord, Walnut Creek and Antioch, where it could reach 105 degrees. Highs could reach 98 degrees in San Jose and 88 degrees in Oakland.
The air quality district includes San Francisco, Alameda, Contra Costa, Marin, Napa, San Francisco, San Mateo, Santa Clara and parts of Solano and Sonoma counties.
David DeBolt covers breaking news. Contact him in Richmond at 510-262-2728. Follow him at Twitter.com/daviddebolt.