Los Angeles County's first significant storm in more than eight months has already forced the closure of the 5 Freeway in Grapevine, unleashed mud on roads and prompted the closure of Malibu's public schools on Monday due to dangerous road conditions.
There is still concern about the potential for mudslides and rock slides in areas of LA County that have recently been burned by wildfires. Just before 4 a.m., severe thunderstorms developed near Catalina Island.
The National Weather Service has issued a flood watch for several recently burned areas, warning of a 10% to 20% chance of significant flash flooding and debris flows capable of damaging roads and homes in wildfire-ravaged areas.
Here's what you need to know:
Implications
Interstate 5 is closed in Grapevine
Interstate 5 was closed in Grapevine, the main stretch of road through Tejon Pass that connects Los Angeles County to the Central Valley.
Grapevine was ordered closed Sunday night, and crews “worked to clear the snow,” Caltrans said He said. Caltrans suggested using US 101 Monday morning Alternative route Between Los Angeles County and Central California.
“The closure will be in place for an unknown period of time,” California Highway Patrol He said.
Malibu Public Schools were closed Monday
Santa Monica-Malibu Unified School District declared All four of its Malibu schools were closed Monday due to dangerous road conditions and challenges accessing the schools. Public schools in Santa Monica are open.
Pacific Coast Highway is affected by flooding
A portion of the Pacific Coast Highway is closed due to flooding in Topanga Canyon, National Weather Service meteorologist Joe Sirard said Sunday. Rain gauges picked up 0.74 of an inch on Topanga Canyon Boulevard at the edge of the fire line, he said.
Caltrans, mudslides forced Pacific Coast Highway west of Topanga Canyon Boulevard. He said Sunday afternoon.
Caltrans' QuickMap website said northbound Pacific Coast Highway was closed at Topanga Canyon Boulevard and southbound PCH was closed from Sweetwater Canyon Road early Monday morning.
Topanga Canyon Boulevard, also known as California 27, is closed. The rain flooded Topanga Creek and debris blocked the road. Caltrans had to be evacuated by crews repairing damage from the Palisades fire He said.
Vehicles stuck in mud
Four vehicles were stuck in the mud on Mulholland Drive around the 4100 block of Alhama Drive in Woodland Hills Sunday evening.
No one needed to be rescued, the Los Angeles Fire Department said, but authorities called in tow trucks to remove the trapped vehicles.
Movement of mud and ash from burnt areas
Officials at Pacific Palisades City Hall said the Los Angeles Fire Department was working to clear mud that had piled up on Palisades Drive Sunday evening, with black ash-laden water reaching the beach.
White-out conditions in the high desert
Caltrans said a section of eastbound California 138 — in the high desert of Los Angeles County — is experiencing white-out conditions due to high tides. Caltrans asked California 138 to avoid its intersection with California 18 between the San Bernardino County line.
Concerns about landslides in recently burned areas
Flood monitoring in burnt areas
A flood watch remains in effect until 4 p.m. Monday for areas burned by the Eden Fire in the Altadena and Pasadena areas; the Palisades and Franklin fires in the Pacific Palisades and Malibu areas; Hughes Fire around Castaic Lake; and the Bridge Fire in the San Gabriel Mountains west and southwest of Wrightwood.
There is a 15% to 25% chance of thunderstorms over much of Southern California through Monday afternoon, bringing heavy rain and slushy conditions.
(National Weather Service)
Water flows rapidly downstream, and in addition to mud, rocks, branches and sometimes boulders – capable of damaging cars and homes – can cause a debris flow. It can be life threatening.
How much rain and snow has fallen
Precipitation
Downtown LA has received 0.47 inches of rain so far from the storm, including 0.11 inches on Saturday.
Saturday's rainfall broke a record dry spell in downtown Los Angeles. The last time downtown received a tenth of an inch or more of rain was on May 5, when 0.13 of an inch fell.
That means that from May 6 through Friday, Downtown LA has gone 264 consecutive days without seeing at least one-tenth of an inch of rain in a calendar day. last Register Feb for this kind of downtown. 25, 2008 to November 3, 2008 for 253 consecutive days.
Here's how much rain has fallen in this rainstorm as of 10 p.m. Sunday:
Fill: 1.36 inches
Pepperdine University: 1.15 inches
Thousand Oaks: 1.13 inches
Calabasas: 1.06 inches
Ventura: 1.02 inches
Santa Monica Pier: 0.98 inches
Northridge: 0.97 inches
Bel-Air: 0.93 inches
Canoka Park: 0.9 inches
Beverly Hills: 0.83 inches
Claremont: 0.56 inches
La Canada Flintridge: 0.53 inches
Downtown Los Angeles: 0.47 inches
Witter: 0.45 inch
Alhambra: 0.4 inches
Culver City: 0.2 inches
snowfall
Heavy snowfall is expected in the eastern San Gabriel Mountains, with total snow accumulations of up to 14 inches, the weather service said. By Monday, snow levels will drop to 3,000 feet above sea level.
Travel on the Mount Baldy, Wrightwood, Mount Wilson and Angels Crest highways will be “very difficult to impossible,” the weather service said Monday morning.
LA stands out for its seasonal rainfall
Downtown LA has now seen 0.63 of an inch of rain since October 1st. That's a drop in the metaphorical bucket of how much downtown gets on average at this point in the season — 6.66 inches. It is 9% on average.
Before this weekend's rain, an unusually dry start to the water year ranked as the second-worst in downtown LA's record books.
The unusually dry conditions keep the vegetation flammable, an explosive compound during strong Santa Ana wind events that can burn quickly if a fire breaks out.
Weather outlook after this storm
Light showers are expected in LA and Ventura counties in the afternoon. Most areas will see partly cloudy skies in the afternoon, the weather service said, and the storm is expected to mostly dissipate by late Monday.
On Tuesday, there is a chance of afternoon showers in the San Gabriel Mountains.
Forecasters expect drier weather later in the week. Clouds and rain are expected over the weekend, mainly for San Luis Obispo and Santa Barbara counties, the weather service said.
