It swamped streets, spilled into buildings, sent mud in motion and roiled rivers where rescue crews aided those swept up in the water overflow.
Then the downpour that stunned the drought-weary Southland with its intensity slunk off in the sun.
But if experts are right, the deluge offered a preview for the wet El Niño winter ahead.
The storm dumped more than two inches of rain on downtown Los Angeles, Santa Monica, Alhambra and other areas in just a few hours. That made it the third-wettest storm in downtown L.A. since the late 1880s, said Bill Patzert, a climatologist with the Jet Propulsion Laboratory.