DANGEROUS STORM: A powerful storm system is hitting Southern California, with snow causing accidents and massive back-ups on the roads and the severe weather sweeping east. KABC helicopter pilot Scott Reiff reports and Ginger Zee with the forecast. https://abcn.ws/2E4Q8AF | ABC World News Tonight with David Muir

What’s the white dome on top of Oat Mountain? It’s the KABC-TV Doppler 7000 weather radar, watching storms move across Los Angeles from one of the highest points in the area. Long before it tracked rain, this exact peak had a very different job. During the Cold War, Oat Mountain was the Radar Control Area for Nike Missile Site LA-88. Radar here once scanned the sky for incoming aircraft and guided interceptor missiles stationed miles away as part of the air defense system protecting Los Angeles.