he's greeted by mayor sean mcallister. in l.a. he'll tape an appearance for the "ellen" show. the president is staying in m milpitas tonight. >> now to a story you'll sea only on nbc bay area, the driver of a car nearly hit by falling concrete on the bay bridge is recounting her terrifying experience. the driver was cruising through a tunnel when a chunk of concrete suddenly came down. cheryl hurd is live on treasure island. >> reporter: it wasn't a fun experience for the driver. the driver tells me tonight it was about the size of a tire and she said she and her friend steered for their lives. >> liz swerved watching the sizable chunk of concrete come into view in slow motion. >> it was big enough to take up the whole wind shooeld. i thought it was going to be like a head on collision, crash. >> she slammed on her brake bracing for impact. >> it scrape long here. this tire got popped. >> a saturday afternoon ruined, leaving this school teacher from kansas city wondering about the safety of the bridge. stli thought the whole purpose of the rebuild to make it sound from what i