UPDATE: Rain Pummels Chatsworth; Scattered Power Outages Hit Region

UPDATE: In the Valley, Van Nuys leads with 6.60 inches of rain as of 11 p.m., Northridge 5.92, Chatsworth Reservoir 5.53, Hansen Dam 5.13, Canoga Park 4.72 and Burbank 4.02, according to National Weather Service.

Forecasters say there is a chance of thundershowers through Monday, then the area gets a respite Tuesday. There is a chance of more rain, but not as heavy, from mid-week on, with temperatures below normal.

A late-winter storm that struck Chatsworth on the first day of spring caused flooding, downed trees and electrical outages.

Scattered power outages were reported in Chatsworth as was flooding on northbound Topanga Canyon Boulevard south of Stoney Point to just north of Chatsworth Street.  The right lane was completely flooded.

At 3 p.m., the storm escalated when severe thunderstorm warnings were
issued for and western Los Angeles County.

A strong band of rain had parked over Chatsworth along the L.A.-Ventura county line from Point Mugu into Simi Valley, and was poised to move east into Malibu and the Conejo Valley, according to the National Weather Service.

About three hours later, the Weather Service issued a flash flood warning for southwestern Los Angeles County, including  Van Nuys, Malibu, Santa Monica, Woodland Hills and Agoura Hills.

Patch reported an on the 170 Freeway.

According to a Weather Service statement, at 5:36 p.m., Doppler radar indicated widespread heavy rain across western Los Angeles County, with a line of intense showers extending from Malibu north to Woodland Hills and . Rainfall rates of more than an inch an hour were reported at several locations in Malibu and the adjacent foothills.

"This rain will produce significant flash flooding and flooding of roadways in western Los Angeles County, including the 101 Freeway from Calabasas through Reseda and on Pacific Coast Highway from Malibu to Pacific Palisades,'' the statement said.

Rock and mud slides are likely to affect Pacific Coast Highway and canyon roads through the Santa Monica Mountains, according to the statement.

"It's a little late in the year for this kind of thing, but we'd consider it a powerful storm any time of year,'' said Weather Service meteorologist Dave Danielson.

Firefighters said the Los Angeles River was running heavily enough for engineers to begin . That forced the routine wet-weather closure of both Burbank Boulevard between Encino and Van Nuys, and Woodley Avenue near Lake Balboa.

One family in an SUV had to be rescued when the vehicle was caught in floodwaters. Because of the wind, a helicopter could not be used, and the family was pulled to safety with ropes, ABC7 reported.

The Sepulveda Tunnel near Los Angeles International Airport was also closed.

In the 24 hours ending at noon Sunday, 2.37 inches of rain had fallen at Topanga Canyon. About 1.4 inches fell at Sylmar and 1.3 inches at Beverly Hills.

There were more than 100 reports of downed trees, mostly in valley areas, and some fell on homes and vehicles, ABC7 reported. Nearly 60,000 Southland homes and businesses lost power, mostly due to the winter storm passing through the area, utility officials said.

About 10,000 Los Angeles Department of Water and Power customers had no
electricity Sunday afternoon, said DWP representative MaryAnne Pierson.

Most of the DWP outages were caused by wind and rain, including downed wires and tree branches getting tangled in wires, Pierson said.

"More of the outages are in the valley areas than in the central areas,'' she said. "We have extra crews, about 38 crews, out repairing things due to the weather.''

Pierson said there were outages in West Los Angeles, the Hollywood Hills, Sherman Oaks, Century City, Chatsworth, West Hills and Sylmar.

City News Service contributed to this report.