As we warned this morning, the current chill to the air is leading to particularly particulate-heavy breathing conditions around the Bay Area. And apparently conditions didn't get any breezier today, thus: the Air Quality Management District has declared tomorrow, Wednesday December 7th to be a Winter Spare the Air Day. Meaning Bay Areans are expressly forbidden from heating their homes by burning actual dead trees, duraflame logs or any other solid fuel.
Also note that Winter Spare the Air days don't include the same admonishment to skip out on internal combustion engines as the Summer season. Assuming your vehicle doesn't run on coal, you're free to drive as much as you like and no one will give you crap for it. (Ha! Just kidding, cars are terrible. Burn your car.)