Then, a little after 6 p.m. on Jan. 7, a fire ignited in a canyon a few miles to the east. Chien needed to report for duty, so the rest of the family packed overnight bags and piled into the car, dropping him off at his station 4 miles away. Kim and the kids took shelter in her office at the nearby California Institute of Technology, where she now works as a safety engineer. Having lived through fires before, they all expected to be home the next morning. But at nearly 80 miles per hour, the wind speeds were beyond anything Chien had witnessed in two decades of fighting blazes in Southern California. The Santa Ana winds were crashing over the mountains like tidal waves, flinging embers far from the main fire and igniting homes in the heart of densely built neighborhoods that, after eight months of no rain, were as dry as the mountain chaparral.