STORM LASHES L.A.: 4 DEAD, TRAFFIC SNARLED; CLEARING EXPECTED TODAY.

Byline: Lisa Van Proyen and Peter Hartlaub / Daily News Staff Writers

A fierce Pacific storm slammed the Los Angeles area Wednesday, but the rainy, windy weather quickly moved on, leaving only a chance of Thanksgiving showers and a Friday that's mostly sunny.

But forecasters said more clouds are expected to roll in Saturday and rain could be in store for the area Sunday, when another storm is expected to bring a 30 percent to 50 percent chance of rain.

While the weather was mostly an inconvenience in the San Fernando Valley, tragedy struck in the eastern part of the county, where two 14-year-old girls died and a 17-year-old boy was missing in a rain-swollen wash.

In all, five teens were swept miles down a wash and into the Rio Hondo shortly after 9 a.m.

Within about half an hour, a 15-year-old boy and a 15-year-old girl had been saved downstream by swift-water rescue teams.

A witness recounted the group's desperate moments.

``The water was high. It was raging. I saw (them) arm-in-arm . . . gasping for air. They didn't even have enough energy to scream for help,'' said Paul Sinquimani, 27, who was drinking coffee at a cafe when he saw three heads bobbing in the water.

Sinquimani watched as the trio was pulled apart in the swirling waters. Then he saw the teens disappear beneath the surface.

``I wanted to save them but I couldn't jump in. The waters were too rough,'' he said.

Also Wednesday, a 30-year-old Rosemead man died after he ran his sport-utility vehicle into the rear of a tractor-trailer on a freeway transition road in Monrovia at 5:25 a.m.

A 70-year-old man was killed after his car was hit broadside by a van at 2:50 p.m. near the intersection of Columbus Avenue and Victory Boulevard in Van Nuys, said Officer James Akana of the Los Angeles Police Department's Valley Traffic Division.

The rain-slick road was a factor, making the van driver unable to effectively brake, Akana said.

The victim, identified as Arturo Saborio of Van Nuys, suffered major head trauma and was pronounced dead at a hospital.

California Highway Patrol officers handled 362 traffic collisions in Los Angeles County alone from 8 a.m. to 5:30 p.m., marking more than five times the number of crashes on a typical day, said Officer Bill Preciado.

Making matters worse, a mainframe computer used to alert Los Angeles fire station crews to 911 emergencies was down most of the day, forcing dispatchers to conduct business the old-fashioned way: via radio.

The rainstorm, which hit hardest during the morning and afternoon rush hours, drenched Southern California and brought pea-size hail to the Pasadena area.

Chatsworth broke its record rainfall for the day Wednesday, with .86 of an inch, compared with its 1981 record of .38, said Stuart Seto, a weather specialist for the National Weather Service in Oxnard.

Elsewhere, Newhall reported .91 of an inch; Glendale .65; the Los Angeles Civic Center .66, and Northridge .51, the National Weather Service said.

The rain measurements are fairly normal for November, Seto said.

``This is our rainy time of year,'' the weather specialist said.

Winds peaked in the Newhall area, where 39 mph gusts were recorded. Commuters in San Luis Obispo County, between the communities of Templeton and Cambria, saw 71 mph winds, Seto said.

Some people fled to the local mountains, where snow levels were expected to lower overnight to 4,000 feet and to 3,000 feet in some isolated areas, meteorologists said.

Some 20,000 customers in portions of Mission Hills, Sun Valley, Sherman Oaks and Woodland Hills were left without power for up to six hours, mostly due to tree branches bumping into power lines, said Ed Freudenburg, a spokesman for the Los Angeles Department of Water and Power.

The rain also caused delays at local airports and created slick road conditions during the busiest times of the day.

One of the most disruptive crashes occurred Wednesday morning on the Hollywood Freeway. A trash truck heading southbound near Victory Boulevard burst through the concrete divider into the northbound lane, colliding with two cars.

The trash truck driver, a woman and her two children went to area hospitals with minor injuries, Los Angeles Fire Department spokesman Brian Humphrey said. Two men in another car suffered serious injuries.

Rain also deluged Santa Clarita Valley roadways, cutting visibility at times to just a few yards, said Officer Doug Sweeney of the CHP's Newhall office.

Capt. David Chavez of Los Angeles County Fire Station 107 in Canyon Country said his crews responded to a four-vehicle pileup in which a woman had to be helped from her overturned car on the Antelope Valley Freeway, just south of Agua Dulce Canyon Road. Two people were hospitalized with minor injuries.

In East Los Angeles, at least one motorist was rescued from atop his vehicle, which he retreated to after his car got stuck in high waters, Humphrey said.

Los Angeles International Airport spokesman Scott Read said the weather caused slight delays for morning flights on the busiest day of the year. Still, there was plenty of parking in the late afternoon, especially in outlying lots.

Roads leading to airports were clogged, but people seemed to be giving themselves enough time to wade through the mess, CHP said.

Dylan Myers, 5, was set to get on a 5:30 p.m. flight to Reno to see his mom. His chaperone, Judy Miller, wasn't taking any chances. She left hOer Simi Valley home at 9 a.m., packing games, magazines and coloring books into a plastic bag to prepare for the long wait at the airport.

Latest storm 0.66 of an inch

Season 2.12 of an inch

Normal 2.61 of an inch

Note: Season total is for the period beginning July 1, 1997, at 4 p.m. as measured at the Los Angeles Civic Center.

LOCAL RAINFALL

(In inches as of 5 p.m. Wednesday)

Chatsworth 0.86

Northridge 0.51

Newhall 0.91

Simi Valley 0.75

Thousand Oaks 0.48

Source: National Weather Service

CAPTION(S):

5 Photos, Chart, Box

PHOTO (1--color) Mother Tami Hirsch and a froggy friend keep Tyler Hirsch, 2, dry in Thousand Oaks.

Michael Owen Baker / Daily News

(2) Monica Silver and Natalie Brainin, both 3, romp in the rain Wednesday at the West Valley Jewish Community Center in West Hills. The storm dropped between 0.51 and 0.86 of an inch of water on the Valley, mostly consistent with normal levels, say meteorologists.

Tina Gerson/Daily News

(3) Fallen garbage cans washed down Sepulveda Boulevard by Wednesday's rain test drivers' skill in the hills south of Ventura Boulevard.

David R. Crane/Daily News

(4) Vehicles ford a flooded underpass in Sun Valley, where police later closed the intersection.

John McCoy/Daily News

(5) Santa Clarita Field Services worker David Smith grabs a street sign loosened by Wednesday's wind and threatening cars.

Myung J. Chun/Daily News

CHART: (color) Rainfall Totals for Los Angeles Area

BOX: L.A. RAINFALL (see text)