Coming after days of rain that washed away hillsides and flooded freeways, the next El Niño storm, set to hit Southern California on Thursday, will focus its damage on the coastline, the National Weather Service said.
"By far the big headline today will be the surf [with] 10- to 15-foot sets over west-facing beaches in L.A. and Ventura counties. We don't normally do surf warnings unless it's over 15 feet," said Curt Kaplan, a meteorologist with the National Weather Service. "It's going to be very strong. With some winds, it could cause erosion."
The Los Angeles County Department of Public Health issued a health advisory for all county beaches through Friday because of storm runoff.
Even if people could go in the water, its probably too dangerous to do so, authorities said, and those on land have to take precautions too.
Early Thursday, the storm was clocked moving east at 35 mph and was reportedly shaking residents in Malibu out of their early morning slumber with thunder and lightning. Pea-sized hail and ground lightning strikes were reported, along with minor street flooding.
Wind gusts could top out at 40 mph, the weather service said.
After days of rainfall that dropped as much as five inches in a single day in some locations, Thursday's precipitation may seem like a sprinkle.
Only about half an inch is expected to be dropped across Southern California, except for isolated areas in the San Fernando and San Gabriel valleys where it may be slightly heavier, Kaplan said.
"We're over the hump. It's nothing like we've had the last two days," he said.
In recent days, storms across the Southland have spawned tornadoes in two counties, flooded freeways, washed away hillsides and buried yards in mud and debris.
The storms are among some of the first effects of El Niño, a series of weather conditions caused by warming of the equatorial waters of the Pacific, weakening rains in South Asia and bringing heavier rains to California. The storms peak in January, February and March.
This year's El Niño is expected to be one of the most powerful ever recorded.
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