Intermittent heavy rainfall, which hit the Southland Saturday morning, is expected to continue through the Easter weekend.
The “unseasonably cold and vigorous storm system” will likely bring rain to most areas, including a chance of thunderstorms, along with mountain snow, according to the National Weather Service.
“The front should push east of L.A. County late Saturday morning,” NWS forecasters said. “The cold upper low will then approach and slowly swing through the area Saturday afternoon through Sunday.”
The storm will be accompanied by gusty winds and the possibility of thunderstorms Saturday night into Sunday, with the best chances on Sunday.
“These thunderstorms on Sunday could produce small hail, gusty winds, frequent lightning and possibly even a small tornado or waterspout,” the NWS said.
Rain totals of 1 to 3 inches are anticipated in coastal and valley areas, with as much as 3 to 6 inches possible along some south-facing mountain slopes.
The NWS issued a flood watch that will be in effect through Sunday afternoon covering the bulk of the Southland, noting that “excessive runoff may result in flooding of rivers, creeks, streams, urban areas, and other low-lying and flood-prone locations.”
The Los Angeles County Public Works Department warned residents about the potential for debris and mudflow in parts of North County due an atmospheric river storm.
Los Angeles County Supervisor Kathryn Barger advised residents to take appropriate precautions in light threatened mudflows.
“Our County will experience another storm system this weekend that brings an increased threat of flash flooding, along with debris and mudflows,” she said in a statement early Saturday. “I am asking residents who were recently impacted by wildfires — such as the Agua and Fish Fires — to remain extremely vigilant and aware of your surroundings. Burn areas and hillsides in particular are vulnerable to debris and mudflows.
“The best way to stay safe is to keep tracking weather conditions, sign up for your local emergency alert systems, and listen to your local news broadcasts. If you receive an evacuation message from local law enforcement officials, follow their directions and don’t hesitate. Prioritizing safety is key this Easter holiday weekend.”
Safety tips are available in various languages at ready.lacounty.gov.
Forecasters said one to two feet of snow could fall at elevations above 6,000 feet, “with even higher amounts at the highest peaks.”
“Snow levels should remain above the Grapevine but there is a 10 percent chance of a snow burst under a thunderstorm,” according to the NWS. “Wind gusts from 60 to 65 mph will pummel the mountains as well but they will diminish Saturday afternoon.”
A winter storm warning will be in effect through 11 p.m. Sunday for the San Gabriel Mountains and the Golden State (5) and Antelope Valley (14) freeway corridors, with forecasters warning that “travel could be very difficult to impossible.”
Cooler temperatures are likely Saturday and Sunday, forecasters said, with most areas not getting out of the 50s.
“There is a small chance (20 percent) the trough will not move fast enough to end the shower activity over L.A. County by dawn Monday,” according to the NWS. “Any lingering showers will not make much of an impact at all. Otherwise, Monday will see clearing skies and warming temperatures as early April sunshine shines on the area.”
Temperatures will warm slightly — as much as 10 degrees in some areas — by Monday, “but maximum temperatures will still end up 4 to 8 degrees below normal.”