LOS ANGELES (CNS) - A destructive storm is making its way out of Southern California Friday, but not before flooding streets, neighborhoods and freeways, causing crashes and congestion, and leading to evacuation orders in recent burn areas.

Heavy rain pummeled most of the Southland Thursday and intensified sparking flooding and mud flows, particularly in Pacific Palisades, Altadena and Pasadena.

Record rainfall was reported in downtown Los Angeles, with 2.8 inches breaking the record for the day of 2.71 inches set in 1954.

The roof of a Smart & Final store in Azusa collapsed during the storm on Thursday. There were no reports of injuries to shoppers or employees at the store.

The storm system began with generally light rain Wednesday, with additional precipitation falling overnight and into Thursday morning across a widespread area. But as the day wore on Thursday, the rainfall intensified, prompting the National Weather Service to issue a series of flash flood warnings for much of eastern, western and central Los Angeles County, including the Eaton, Palisades, Franklin and Bridge fire burn areas.

According to the NWS, rainfall rates were recorded in some areas at levels as three-quarters of an inch to 1.2 inches per hour -- well above the rate that can typically trigger flooding or debris flows.

Storm runoff was seen racing down streets in the Pacific Palisades area, carrying mud and debris as it overwhelmed a catch basin and cascaded onto a fortunately empty street. NWS forecasters said law enforcement in the area was reporting multiple vehicle inundated by mud across the burn area.

In the Hollywood Hills, the Los Angeles Fire Department reported a debris flow that parked 8 inches of mud on Mulholland Drive. No injuries were reported, but crews scrambled to ensure the safety of structures above and below the slide area.

Mud also swamped parts of Malibu Canyon and Pacific Coast Highway -- roadways that were closed prior to the storm's arrival.

In issuing flash flood warnings, NWS forecasters said, "There is now a high risk for a life-threatening debris flow."

As of early evening, however, there were no reports of any injuries from the storm.

The flood warnings covered areas including Malibu, Topanga State Park, Pacific Palisades, Brentwood, Topanga Canyon Road through the Santa Monica Mountains and Mandeville Canyon, Malibu Canyon and Las Virgenes roads through the Santa Monica Mountains, Mount Wilson, Pasadena, Altadena, Sierra Madre, Arcadia, Monrovia, Chatsworth, Northridge, Woodland Hills, Encino, Van Nuys, Santa Clarita, North Hollywood, Beverly Hills, Santa Monica, Universal City, Burbank, Hollywood, Venice, Culver City and Griffith Park.

Evacuation warnings went into effect at 7 a.m. Thursday for recent burn areas within the city of Los Angeles. Those orders affected:

-- Palisades Fire area: Getty Villa area, Highlands near the burned areas, Bienveneda area near Temescal Canyon Park, Reseda Blvd area/Marinette Road near Will Rogers State Park, Mandeville Canyon above Tanners Road.

Sunset Fire area: East and South of Runyon Canyon.

Hurst Fire area: Olive Lane in the Oakridge Mobile Home Park.

Some individual property owners in those areas whose homes were considered to be at heightened risk were given mandatory evacuation orders. As of 8:30 a.m. Thursday, those orders affected 106 homes in the Palisades Fire area, nine in the Sunset Fire area and four in the Hurst Fire area, according to Los Angeles Police Department Chief Jim McDonnell.

LAPD officers went to each of those affected homes to notify them of the order. Those homeowners also received electronic notifications, and door- hangers were left at their homes if police were unable to contact them. McDonnell also said no private contractors were being permitted in the Palisades burn area Thursday due to the evacuation warnings and orders.

The evacuation orders and warnings were expected to be in effect until at least 2 p.m. Friday, depending on the storm.

Evacuation warnings also stretched into the Malibu area. All Malibu campuses in the Santa Monica-Malibu Unified School District were closed Thursday "due to road closures and weather concerns." District officials said the closure may extend into Friday depending on weather conditions.

Additional evacuation warnings were issued in the San Gabriel foothills near the Eaton Fire burn area, affecting thousands of residents. The city of Sierra Madre issued mandatory evacuation orders Thursday morning impacting nearly 1,000 residences.

Los Angeles County Sheriff Robert Luna said individual homes in areas patrolled by his agency were also given mandatory evacuation orders if their properties were considered at risk. Speaking to KNX News Thursday morning, Luna said authorities were taking a "surgical" approach to the mandatory evacuations to specifically target hopes considered at heightened danger.

He said mandatory evacuations as of Thursday morning were issued for nine homes in Altadena, 49 in Malibu, five in San Dimas and 35 in Palmdale.

In Orange County, mandatory evacuations were ordered in areas near the Airport Fire burn area. The orders were in effect for Trabuco Canyon, including the RC Airport, fire station, campground/park and school; Bell Canyon, including Starr Ranch; and Hot Springs Canyon, including Lazy-W Ranch.

Evacuation warnings were in place for Long Canyon and Modjeska Canyon.

O'Neill Regional Park was also closed Thursday, including the campgrounds.

A dormitory-style shelter was set up at the Foothill Ranch Library Program Annex at 27002 Cabriole Way, for Orange County residents leaving the area during the storm.

L.A. County public works crews worked for days in advance to prepare for the storm -- emptying debris basins, clearing storm drains and distributing sandbags to residents. In the Eaton Fire burn zone, the county Department of Public Works and the sheriff's department warned residents living in homes that may be at high risk of damage from mudslides or flooding, and advising them to prepare to evacuate.

The NWS has described the multi-day storm system as likely to be "the biggest precipitation producer so far this season."

By the time the storm exits the area on Friday, roughly 1 to 3 inches of rain are expected in most coastal and valley areas, with 3 to 6 inches anticipated in the foothills and mountains.

Los Angeles County Public Works Director Mark Pestrella said rainfall rates that exceed a half-inch per hour can lead to mud and debris flows, although factors such as topography, the soil system, geology and the status of the flood control system all contribute to the potential for such occurrences. He insisted, however, that crews have been working around the clock to ensure the county's 154 debris are clear and have the capacity to capture mud and debris that could descend mountain slopes.

Pestrella said that while the county worked to notify residents in the fire zones whose homes may be at increased danger of experiencing mudslides, he urged residents who think they may be at risk to contact the county at 800-675-4357 to have their property evaluated. The service is available at any county location, not just the recent fire areas.

"This service is going to be provided right up to and to the point that we can no longer get to your properties," he said.

Pacific Coast Highway remained closed to the public between Chautauqua Boulevard in Pacific Palisades and Carbon Beach Terrace in Malibu due to concerns about possible mud slides or debris flows. Topanga Canyon Boulevard was closed between PCH and Grand View Drive.

A series of road closures were also in effect in Malibu, including Malibu Canyon Road between Piuma Road and Adamson Flats. Residents only were being given access to Las Flores Canyon Road between Rambla Pacifico and PCH; Piuma Road between Cold Canyon and Rambla Pacifico roads; Rambla Pacifico between Piuma and Las Flores Canyon roads; Saddle Peak Road between Stunt and Tuna Canyon roads; Schueren Road between Saddle Peak and Piuma roads; and Tuna Canyon between Saddle Peak and PCH.

Bill Handel