The driver flicked a LIT cigarette out her window and it landed in front of my car and ambers went everywhere. Her right blinker was on and she was swerving to the shoulder and back again. I followed her past 3 exits still with her blinker on and she never turned until we got to the exit off HWY 99 for 16th avenue. I filmed her driving (hands free dash video) and I pulled up beside her and she was eating while driving which may be the swerving. Completely careless when we all can barely breath in this horrific smoke!