Southland Takes a Breather Before Next Storm : Weather: Orange County gets a bit of drizzle. Next big system, set to hit today, is expected to pack a wallop.

Given a respite Saturday to sift through the ooze and debris left by subsiding floodwaters, Southern California and Baja California braced for the next punch from a powerful storm system expected to move in by today and soak the region’s saturated terrain.

From Tijuana’s battered barrios to Riverside County’s soggy farmlands, work crews scrambled Saturday to tally the devastation, shovel away mud and place sandbags before the next downpour. Weather forecasters said to anticipate up to an inch of rain in the Los Angeles area, 1 to 2 inches elsewhere along the coast and 4 to 6 inches in the mountains and foothills.

Only traces of rain had sprinkled Orange County by Saturday night, according to WeatherData Inc., which provides forecasts for The Times. Santa Ana got the most rain with 0.27 of an inch, forecasters said. The county has received 4.5 inches of rain since Jan. 1.

Flood watches were in effect from the San Jacinto Mountains south into San Diego County and northern Baja California. Heavy rain was again headed for Tijuana, where last week’s floods left at least 15 dead and sent 2,800 people to improvised shelters.

Dark clouds that had cast a leaden pall over much of the Southland Saturday afternoon only seemed to inspire Ron Shap, who used the opportunity to work on a moody, impressionistic painting of the downtown Los Angeles skyline.

Sitting on a folding chair near 1st Street, the 52-year-old artist dabbed at his artwork even as heavy raindrops began pelting it, causing the colors to begin running together.

“It doesn’t matter,” Shap said with a grin. “These are watercolors.”

Along the coast, road crews blasted boulders to guard against rockslides. A Malibu sheriff’s sergeant, preparing for a day on the region’s winding canyon roads, left his patrol car behind in favor of a four-wheel-drive truck.

In Tijuana, the latest weather reports made officials fear that the worst was yet to come. With that in mind, hundreds of Eastside Los Angeles residents rallied to lend a hand by donating supplies.

Meanwhile at least a dozen Orange County residents--part of a caravan of U.S. cars and trucks with donated food, clothing and water--arrived in the Mexican community.

For most of the day, blue skies bathed the Mexican border city in sunshine, luring droves of U.S. shoppers who ignored the muddy sheen that glistened on most streets to go bargain-hunting along the glitzy Avenida Revolucion.

But authorities--worried that the respite had stirred a false sense of security--issued repeated warnings and made plans to evacuate another 1,000 residents from colonia La Piedrera.

Of growing concern is the swollen Rodriguez Reservoir, southeast of downtown. Government officials, who have flown in engineers from Mexico City to study the situation, say that the reservoir is at 70% capacity and may have to be drained if water levels rise significantly.

On Saturday, the U.S. Coast Guard joined San Diego city officials in providing machinery and equipment to beleaguered Mexican workers still struggling to rescue stranded residents. Two Coast Guard helicopters picked up at least 35 people in small towns between Tecate and Tijuana. Still, by late Saturday, eight colonias remained isolated by mud and standing water.

In the working-class colonia Chula Vista, several evacuated residents returned to sift through the rubble of what was once their homes. Juan Manuel Robles used a broomstick to poke through layers of gooey mud, looking for valuables.

But anything worth saving, he said, had been stolen by looters.

“My mother-in-law lived in this house for almost 30 years,” Robles said. “She had hundreds of personal treasures inside, pieces of her life that are impossible to reproduce. There is nothing to save, nothing.”

On Los Angeles’ Eastside, hundreds of residents pitched in, delivering goods to churches, community centers and private homes designated for relief efforts.

In Orange County, Goodwill Industries offered its collection bins as church workers and relief officials made pleas for blankets and disposable diapers.

“Although a border separates us, we’re so close together that we need to help each other,” said Jackie Murguia, co-founder of the Assn. of Baja Californians, which set up seven collection centers from San Bernardino to Huntington Park. “In times of disaster, we have to come together as human beings.”

Meanwhile, the storm that wreaked such devastation on Tijuana continued eastward, forcing Arizona officials to declare a statewide flood emergency and urge hundreds of people to evacuate low-lying rural communities.

Helicopters were sent to rescue Navajo families from the Birdsprings and Leupp areas of their reservation, and about 350 people were evacuated from along the Gila River in Winkelman, a mining town about 70 miles north of Tucson.

And with moist, tropical air being sucked from the Pacific along an especially powerful jet stream, forecasters predict another pounding by Tuesday.

“It’s just one after the other,” said Steve Burback, a meteorologist with WeatherData Inc., which provides forecasts for The Times.

The newest series of storms could be especially troublesome because the ground is nearly saturated.

“The additional heavy rain will probably result in flooding, which will range from urban flooding of freeways, streets and low-lying areas to the much more dangerous flash flooding of creeks and streams,” according to a National Weather Service advisory issued Saturday.

“Extensive rock and mudslides will probably occur in canyon areas,” it added, also warning that river flooding was possible.

Beaches from Pacific Palisades to the Palos Verdes Peninsula remained closed Saturday, a day after 4 million gallons of partially treated sewage was released into Santa Monica Bay.

A heavy snow warning was issued for the mountains. Last week’s rain had created icy slopes at the Mt. Waterman ski area in Angeles National Forest, prompting officials to close it. The Mt. Baldy ski area was also closed because of a rockslide near its parking lot.

Katz reported from Los Angeles and Reza from Tijuana. Times staff writers Bob Pool, Eric Young and Marc Lacey contributed to this report.

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