A life-threatening, widespread windstorm that could be one of the most destructive to hit Southern California in over a decade will roar to life Tuesday and also create extremely dangerous fire weather conditions.

Strong winds — with gusts as high as 79 mph in the San Gabriel Mountains — began blowing their way through Southern California on Tuesday morning, Jan. 7, leading to the possibility of downed trees and wires, power outages and dangerous fire weather.

Millions of people across Southern California are under a Red Flag warning as a dangerous windstorm starting Tuesday could bring widespread destruction and extreme fire risk to the area, with emergency services braced to provide a huge response.