To understand the power and potential dangers of El Niño, look at satellite images of the Pacific Ocean on Sunday.
At least four storms were brewing — the farthest still getting going in Asia — and all aimed at California.
It's this pattern, a series of back-to-back-to-back storms seemingly arriving on a conveyor belt, that concerns officials bracing for potential damage from the predicted winter of heavy rains.
Water and Power is The Times' guide to the drought. Sign up to get the free newsletter >>
"El Niño storms: it's steady, not spectacular. But it's relentless," said Bill Patzert, climatologist at NASA's Jet Propulsion Laboratory in La Cañada Flintridge. "It's not 10 inches in 24 hours and nothing afterward. It's a 1-inch storm, a 2-inch storm, followed by a 1-inch storm, followed by a 2-inch storm.
"As this goes on for many weeks, then you start to soak the hillsides — then you get more instability. And then, instead of having 6 inches of mud running down your street or off the hillside behind your house, then you can get serious mudflows — 2 to 3 feet in height."