201901.05
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Flash flood warning issued Saturday night for Woolsey fire burn area

by in News

LOS ANGELES — The first winter storm of 2019 moved into Southland on Saturday, bringing with it rain, snow and fears of flooding and mudslides on mountain slopes recently scorched by wildfires.

Showers hit Riverside in the late afternoon Saturday, Jan. 5, 2019. (Photo by Cindy Yamanaka, The Press-Enterprise/SCNG)

Forecasters estimated this storm will bring a half-inch to an inch of rainfall across the Southern California coast and valleys and more than double that amount in higher elevations, making it similar in size to the early December system that sent mud and rocks cascading onto roads and forcing evacuations in some areas.

The strong Pacific system, originating in the Gulf of Alaska and predicted to batter portions of Northern California, began pouring into the Southland Saturday and was expected to continue through Sunday.

“A powerful storm will slam … with heavy rain, high winds, heavy snow as low as 3,000 feet, and beach hazards,” according to the National Weather Service, which first issued a flash flood watch for areas recently burned by the Hill and Woolsey fires —  then at 7:46 p.m. issued a flash flood warning for Woolsey burn areas including Malibu, Agoura Hills, Oak Park and Westlake Village. The warning was to expire at 10:45 p.m.

It’s part of a moderate El Nino weather pattern that experts said will continue to bring more precipitation to some regions of the state, with the outlook for the next few months indicating above-average rainfall.

That’s welcome news for Southern ski resorts that may celebrate 4 to 8 inches of fresh powder this weekend, and up to three feet in the northern Sierra.

“Snow could reach 40 inches in places,” NWS officials said.

As rain poured across Southern California on Saturday, Jan. 5, debris flows became a concern in Woolsey fire burn areas. Cars are seen here driving along slick roads in Monrovia. (Photo by Jonah Valdez/Southern California News Group)

Residents in areas recently burned by wildfires — where the soil does not absorb a lot of moisture and can be prone to hazardous mudflows that carry dirt, rocks and larger debris — need to be prepared, experts warned.

Weather forecasts and warnings will not be interrupted by the ongoing federal government shutdown, NWS officials said. Updates will be provided on the agency’s website and social media feeds.

December’s similarly sized storm plagued the Southland with debris flows, flooded freeways and dangerous driving conditions, prompting road closures and mandatory evacuation orders in the recently burned Holy Fire area of Orange County.

The December storm did not prompt evacuation orders in the Malibu area, although some hillsides scorched in the Woolsey Fire sent mud and rocks cascading onto select mountain roads during a morning commute on Pacific Coast Highway near Leo Carrillo State Beach.

Malibu officials were readying themselves for this weekend’s storm, notifying residents of the potential risks and possible evacuations in the burn area as well as forecasted high surf and dangerous rip currents along the coastline. City crews were clearing storm drains and culverts and placing temporary concrete blocks to stop potential debris flows. Free sandbags were being distributed at Malibu area fire stations.

“Flooding, mud and debris flows are a very real and dangerous threat to the communities affected by the Woolsey Fire,” according to a statement from the city. “It is important to plan and prepare. Prepare for lack of water, power and natural gas, non-functional traffic signals, and roads that may be impassable. Mud and debris flows can have a devastating impact, including loss of life and home. Residents are urged to prepare for possible evacuations. Evacuation orders should not be taken lightly.”

Forecasters said the peak rainfall in the Woolsey fire area was expected between 8 p.m. and midnight Saturday, with rainfall rates of a quarter- inch and half-inch an hour.

It’s a similar story in Riverside County, where the Cranston and Holy fires burned. In preparation for the upcoming storm, flood control crews were working throughout the week to clear mud that slid into the McVicker Basin in the December storm. County officials expected the mud to be fully removed before the rain started.

Los Angeles County residents can find out more about storm preparation and safety tips at www.lacounty.gov/larain.

Also Saturday, the National Weather Service posted photos on social media of a funnel cloud off the coast of Long Beach. There were no reports of it touching down.

 

The Daily News contributed to this report.