Picture this: you’re driving across the Golden Gate Bridge in the morning and turn the dial on the radio and hear, “We got a pileup on 880 that has triggered a SigAlert.” But what exactly is a SigAlert and why do we call it that? Back in the 1940s the LAPD would notify local radio reporter Loyd Sigmon about particularly bad accidents. Maybe he got sick of all the phone calls, because Sigmon ended up creating a special device that authorities could use to alert the media to particular traffic troubles. There was little faith in the invention initially, and the police chief at the time flippantly named it a “SigAlert.” Many years later, Caltrans latched on to the term, and a SigAlert has come to be known as any traffic incident that will tie up two or more lanes of a freeway for two or more hours. While most Southern California stations use the term, it isn’t a statewide convention. The most prominent station in the Bay Area utilizing it is KQED.