The Dry Facts: Forecasters Say Really Big Storm Is Over Horizon : Weather: Keep the umbrella handy. Another potent rainmaker expected to hit Monday night could pack an even bigger punch.

Orange County was beginning to dry out Saturday after the fierce 48-hour winter storm that blasted most of the state, but hold onto those galoshes, because this weekend’s sunshine should prove to be fleeting.

Another powerful storm system is expected to arrive late Monday, bringing with it the possibility of an even harder dousing of rain, forecasters said.

“It looks pretty powerful,” said Steve Burback, a meteorologist with WeatherData Inc., which provides forecasts to The Times. “It should hang around a couple days and be a significant rain producer.”

News of dark clouds on the horizon made most regional water officials happy. But they were quick to note that even a few more storms before summer won’t produce the kind of rainfall needed to turn California’s five-year drought into a soggy memory.

“Our predictions are that if we have a normal year from here on out, meaning two or three more storms, we’d still be critically short” of water, said Keith Coolidge, a spokesman for the Municipal Water District of Orange County. “Still, it’s better than nothing. Every little bit helps.”

Coolidge said the downpour that began last Wednesday and didn’t let up completely until Friday should help to renew the subterranean ground-water basin that supplies several communities in northern Orange County.

But the rain came so fast and furious that much of it was flushed out to sea via local rivers and storm drains before the water could percolate into the earth. Even in the teeth of the drought, authorities were forced to release 6.5 billion gallons of water from Prado Dam that mostly flowed uselessly down the Santa Ana River into the ocean.

“There was so much rain in so short a period that most of the water probably didn’t have time to settle into the ground,” Coolidge said, noting that the county’s seasonal rainfall remains about half of normal for this time of year.

Even some local farmers were grumbling that the rain of last week and the storm expected Monday may be too much of a good thing. Strawberry farmers, in particular, have seen their crops battered, forcing them to sell the fruit for juice.

“We were just starting to roll with a few berries here and now this comes along,” lamented Johnny Magarro, who has 140 acres of strawberries in Irvine. “The rain rots the berries right on the vine, turns them into mush. . . . But I’d rather us lose some berries now instead of have severe water cuts later. The rain will help in the long run.”

Out at the beaches, lifeguards were still contending with mud-colored water made murky by runoff laced with everything from tree stumps to oily residue from local roads.

“It’s not so much logs out in the surf now, mostly just leaves and branches and weeds and trash,” said Jeff Aldinger, a lifeguard in Seal Beach, where the beach was shut down on Friday because of the flotsam and filth in the ocean. “It’s still pretty dark, pretty muddy-looking.”

By Saturday, county emergency road crews and other cleanup personnel had finished mopping up most of the storm debris and damage inflicted on the area. The rain and winds caused mudslides on various canyon roads, toppled power lines, prompted a 20-car pileup on Interstate 5 and resulted in one rain-related traffic fatality.

In addition, a 20-year-old Fullerton College student died after she was thrown from an inflated raft into a “violent current”’ in the rain-swollen Santa Ana River. Despite a dramatic helicopter rescue, Bonnie Davis of Orange died late Friday at UCI Medical Center.

More than 12 inches of rain doused Santiago Peak in eastern Orange County. In Santa Ana, 4.84 inches fell during the three-day storm, while Newport Beach had 3.87 inches and San Juan Capistrano 5.2 inches, according to Burback of WeatherData.

Burback predicted mostly clear skies in Orange County today, with temperatures in the lower 60s along the coast and low 70s inland.

But clouds could start to build up tonight, leading to another deluge by Monday night. The rain should continue steadily into Tuesday before tapering off completely on Wednesday, Burback predicted.

The storm was building in the vicinity of the Hawaiian Islands on Saturday, picking up a full load of tropical moisture, he said. While temperatures should be in the upper 50s and 60s throughout the county, the mercury should drop as the storm lingers and winds could pick up to 35 or 45 m.p.h. along the coast.

If the temperature does fall as expected, the snow level in Southern California mountains should drop to about 5,000 feet.

“It looks like a bigger one than last week,” Burback said as he eyed a satellite photo of the swirling storm. “It will be a slow mover, it won’t zip right through. But once it does, there should be a break in the weather until next weekend.”