Biggest Storm in Years Soaks Southland : Rain: Pelting won’t let up until Tuesday, forecasters say. Heavy weather includes a tornado in Irvine.

After months of unrelenting dryness, the biggest storm in years slashed Southern California on Thursday with heavy downpours and a rare tornado that touched down in Irvine, damaging about 50 condominiums and several mobile homes, but causing no injuries.

The rainfall at the Los Angeles Civic Center totaled 2.44 inches in the 24-hour period that ended at 4:30 p.m. Thursday.

The last major storm was on Feb. 14, 1986, when 2.5 inches of rain fell in a 24-hour period, according to WeatherData Inc., which provides forecasts for The Times.

Up to 2 more inches could fall in some coastal areas before what was described as a wave of storms ends early next week, said WeatherData meteorologist Steve Burback.

“It’s going to be pretty much continuous,” Burback said. “I don’t see any real clearing, or dry period, until Tuesday.”

By late Thursday, the first storm, which began late Wednesday morning, had dropped 3.16 inches at the Civic Center, bringing the season’s total to 4.54 inches. Normal would be 11.07 inches.

Elsewhere in the Southland, Pasadena had recorded 4.5 inches since late Wednesday afternoon; Newhall, 4.18; Northridge, 4.13; Monrovia, 3.57; Woodland Hills, 3.14; San Bernardino 3.04; Long Beach, 2.26; Culver City, 2.00; Palm Springs, 1.90; Santa Monica, 1.87; Santa Barbara, 1.49, and Anaheim, 0.78.

In Ventura County, 5 to 8 inches fell in the mountains north of Ojai, with 2 to 4 inches recorded in most other areas. It was the county’s heaviest single day of rain since 2.84 inches fell in the city of Ventura on Valentine’s Day, 1986, officials said.

Runoff from the heavy rain caused a 2-million-gallon overflow of partially treated sewage in Ballona Creek, which empties into the Pacific at Marina del Rey, forcing the closure of beaches all along the Los Angeles coastline.

City officials estimated that up to 15 billion gallons of polluted water from sewers and storm drains had entered Santa Monica Bay, an unusually large amount, even in a major storm. They attributed that to the long dry spell, which caused storm drains to fill with toxic chemicals and organic pollutants.

Some Orange County residents were shaken Thursday afternoon when a tornado descended from a roiling black sky and dipped into their quiet neighborhood east of Irvine Valley Community College.

The windstorm ripped off shake and tile shingles and broke windows in 45 to 50 condominiums as well as in several mobile homes.

The twister struck at 12:45 p.m. and caused heavy damage to 15 or 20 of the structures, Irvine Police Lt. Vic Thies said. There were no injuries. No damage estimates were immediately available.

“It was kind of a mini Wizard of Oz,” Thies said. “But we rescued all the Totos.”

The last reported twister in Southern California touched down in 1987, when a fierce storm damaged about half-a-dozen mobile homes in east Lancaster.

National Weather Service meteorologist Bill Hoffer said such phenomena are created when “the atmosphere over our area becomes unstable, when you have warm air clashing with colder air. . . . It’s basically Mother Nature just trying to balance herself out.”

One stunned Irvine resident, Gary Hicks, after hearing noise, opened his bathroom window to look outside.

“I could see up into the funnel,” he said. “I could see the debris.”

The swirling winds were sucking up and spitting out fences, roof shingles and tiles, patio furniture and even car parts. Hicks said he slammed his window shut, but continued to watch as the tornado moved away, touching down again and moving off into nearby orange groves.

Hicks’ neighbor Stephanie Leggee said she was standing in front of her living room window when she heard the deep rumbling of the approaching tornado.

“I saw a large funnel cloud with a board spinning around in it,” Leggee said.

Although it missed her house, it spun her car completely around, and “sucked up the hood” as if she were about to check the oil.

“It happened so fast,” she said with wonder.

In Los Angeles’ El Sereno district, mud inundated a home in the 4500 block of Dudley Drive during the storm Wednesday night, causing major damage, but no injuries, fire officials said.

To the north, rainfall totals were between 1 and 2 inches at most cities from Santa Rosa south to Santa Maria, the NWS said.

So far, snowfall amounts in the Sierra have not been very heavy, with accumulations of 7 inches or less, but forecasters said more was on the way.

Heavy snow was reported in the Southland mountains as low as 5,500 feet. The Big Bear area in the San Bernardino Mountains had more than 6 inches on the ground. Similar amounts were reported in the San Gabriels, with up to 15 inches expected by tonight.

The storm ripped away a nylon canopy above the new San Diego Convention Center, cut off power to more than 39,000 area homes and spawned a waterspout over the ocean.

Times staff writers Tina Anima, G. Jeanette Avent, Leslie Berger, Bettina Boxall, Christopher Pummer, David Reyes and Bob Schwartz contributed to this story.

THE RAIN

24-hour total (as of 4:30 p.m.): 2.44 in.

Storm total: 3.16 in.

Monthly total: 3.16 in.

Total for season: 4.54 in.

Last season to date: 5.43 in.

Normal season to date: 11.07 in.

Figures, based on 7 p.m. Thursday readings at the Los Angeles Civic Center, were compiled by the National Weather Service.