The biggest rainstorm since February is expected to hit parts of Southern California starting on Tuesday, according to forecasters.
Light rain began falling Sunday on the parched region and possible burst of intense, heavy rain was accumulating over the Pacific and expected to make landfall mid-week.
"We're going to see some good rain when we get into Tuesday," NBC4 meteorologist David Biggar said.
Local news from across Southern California
About a tenth of an inch was expected in the LA basin before Monday, possibly up to a quarter inch in the foothills and mountains. But it was the second wave of the storm on Tuesday that was described as the real rainmaker.
The center of the storm might hit the Central California coast, instead of Los Angeles, but 6-8 hours of intense rain was still expected by the NWS, to fall during the day on Tuesday.
The winds coming out of the south mean clouds will hit the local mountains head-on and dump rain on the south-facing foothills, like the recent fire areas near Azusa and Malibu, according to the weather service.
"There is a chance of a 2-to-3-hour burst of very heavy rainfall with this storm, which will bring the threat of flash flooding and mud and debris flows in and around recent burn areas," the NWS warned, adding that scattered rain might continue into Thursday.
One to 2 inches of rain were expected for the coasts, with 2 to 5 inches near the foothills and mountains of LA.
The subtropical nature of this rain means the freezing level will be quite high, above 7,500 feet, and only the highest mountains near Wrightwood will get snow.
Snow is important for the long-term implications of California's pernicious, extreme drought, now stretching over 80 percent of the state.
It's taken years for the dry conditions to build, in part because the Sierra Nevada snowpack has receded, according to the Weather Channel, so this week's rains is mostly a drop in the bucket on the way to California's recovery.
The City News Service contributed to this report.