May Showers Bring . . . Snow?

A late-season Alaskan storm dumped unusually heavy rain on Los Angeles and some rare May snow on Southern California’s mountains Tuesday. Forecasters said the unseasonably cold, damp weather--perhaps a parting shot from El Nino--should continue through today.

The National Weather Service issued a “winter weather advisory,” calling for up to a foot of snow by dawn today--just 39 days before the official start of summer--in the San Bernardino, San Gabriel and Tehachapi mountains above 5,000 feet.

“It’s unusual, but it’s not unprecedented,” Tim McClung, a National Weather Service meteorologist, said of the advisory. “In Southern California, nothing’s unprecedented.”

Nonetheless, Tuesday was the coolest May 12 on record in Los Angeles, with a high reading on the Civic Center thermometer of only 58 degrees. The coolest previous maximum reading was 61 in 1935. The normal high for the date is 74 degrees.

Woodland Hills was even cooler, getting no warmer than 54 degrees. Van Nuys and Burbank both hit 61.

As Los Angeles nears the end of a rainfall season that was about twice as wet as usual, thanks to El Nino, this storm could be one of the final blows, according to Kevin Stenson, a meteorologist with WeatherData Inc., a firm that provides forecasts for The Times.

Stenson said that although the El Nino meteorological phenomenon is waning, it still packs enough punch to split the storm track formed by high-altitude jet stream winds. A northern branch follows the usual track east across British Columbia and another swoops south down the Pacific Coast and across Los Angeles.

The current storm raveled the Los Angeles branch, dropping .67 of an inch in Woodland Hills by 5 p.m. Tuesday, more than three times the average amount for the entire month. That raised the Woodland Hills precipitation total so far this May to 2.82 inches--nearly 16 times the .18 inch May average.

Burbank got .73 of an inch as of 5 p.m., Van Nuys .51 of an inch and the Civic Center .76.

The off-and-on downpours were held responsible for a good many of the 430 accidents on local freeways--and that was just as the afternoon rush-hour began--including a 12-car midmorning pileup on the westbound Ventura Freeway in Calabasas that sent three people to hospitals.

The rain also washed out four high school league tennis championships and more than five dozen high school baseball and softball games, including the first round of the City Section softball playoffs.

The snow level in Southland mountains dipped below 5,000 feet Tuesday afternoon--and could drop an additional thousand feet or more before dawn today.

Genevieve Paquet, a spokeswoman for the Snow Summit ski resort in the San Bernardino Mountains, said the snow that began falling at the 7,000-foot level there Tuesday afternoon was expected to continue through the night.

“Unfortunately, our ski season ended May 3,” she said. “Right now, we’re getting ready for a springtime bicycle race that’s scheduled for this weekend.”

The race probably will go on as scheduled at the Big Bear Lake resort, “but we may have to clear out a little snow in some places to do it,” Paquet said. “Snow this late is not typical spring weather up here.”

Forecasts called for between 6 and 12 inches of snow by dawn today at levels above 5,000 feet.

Records on such things are hard to come by, but it was difficult to find anyone who could remember that much snow that low in May.

“It’s definitely an oddity,” meteorologist McClung said.

The rain and snow are expected to stop--at least for a while--on Thursday morning, Stenson said.

“We’re keeping our fingers crossed, but right now, it looks as though this storm should scoot out of Southern California by then,” he said. “On the other hand, there’s another one lurking out there in the Gulf of Alaska.”

Although El Nino has been the talk of the town largely for its powers of destruction, it also deserves credit for topping off municipal water reserves and even saving homeowners a little cash on their water bills.

Department of Water and Power customers spent an average of one-third less on their February-March water bill this year, a savings of about $14 per household, said DWP spokeswoman Karen Shepard-Grimes. From December through April, the average customer has used 11% less water than last year.

While the wild weather has been saving DWP customers a little lawn-watering money, though, it has been costing those in the air-conditioning business. With temperatures in the 50s and 60s, so few people have been running their air conditioners that repair work is down 50% compared with last May, said Sophia Gorgis, manager at at GTK Service Co. in Van Nuys.

So how have the four employees at GTK been spending their days?

“We sit and play with the computers,” Gorgis said. “It’s bad.”

Times staff writers Claire Vitucci and Michael Lazarus and correspondent Lauren Peterson contributed to this story.

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May Rainfall in the Valley

Average rainfall for May, as measured by a weather station in Woodland Hills, is only .18 inches. But as of 5 p.m. Tuesday, 2.82 inches have fallen this May. Another .56 inches by May 31 would beat the record set in 1977.

1956: 1.57 inches

1977: 3.37 inches

1998: 2.82 inches (to date)

Source: WeatherData Inc.