LA NINA COOLING HOPES FOR RAIN BUT IT'S TOO EARLY FOR PREDICTION OF DRY WINTER FOR SOUTHLAND.

Byline: Dominic Berbeo Staff Writer

Despite reports of her demise, La Nina still holds Southern California in her dry grip, leaving the region's rainfall more than 2 inches below average, experts said Wednesday.

While freezing rain and snowstorms hit hard across the nation, Los Angeles is headed toward another under-average rainfall year. Only 1.21 inches has fallen since July 1, compared with the average of 3.61 inches by Dec. 13, forecasters said.

``La Nina is reluctantly leaving, but definitely having an effect here,'' said Kelly Redmond, a climatologist with the Western Regional Climate Center in Reno, Nev.

``But we've had a number of years where it picks up and we get a gangbuster of a rain season later on in the season. It's still too early to start talking about having a dry season.''

Water officials said Los Angeles is not in danger of drought because the upside of a lingering La Nina is that the Sierras have been walloped with heavy snowstorms.

Forecasters predicted scattered early morning showers for today, which could bring about one-tenth of an inch of rain, said Ray Tanabe, a meteorologist with the National Weather Service. The valleys, foothills and mountain areas will receive the most rain.

Highs today are expected in the mid-50s to 60s in most parts of the Valley, with overnight lows in the mid-40s to lower 50s, he said.

A tropical low-pressure system moving southeast over the Pacific Ocean should dissipate by this afternoon - giving way to a clear and crisp weekend, he said.

According to NWS figures, Southern California got off to a slow rainy season this year, a repeat of last year's season during which only 0.44 of an inch of rain had fallen as of Dec. 13.

Climate experts have been debating whether La Nina's waning heralds a 10- to 20-year drop in average rainfall in the Pacific Basin, referred to as the Pacific Decadal Oscillation.

While some have said the two-year La Nina pattern had finished, oceanographer William Patzert agrees with Redmond that it is lingering and says the region could be entering an even longer dry pattern.

The climate patterns known as El Nino and La Nina are typically two-year variances in Pacific Ocean water temperatures near the equator that have an effect on the jet stream, Patzert said.

La Nina typically raises the jet stream away from Southern California, causing drier-than-normal weather. El Nino causes cooler, wetter rainy seasons in the United States' Southwest.

``What we're seeing in satellite photos is the tropical South Pacific tends to be cooler in dry spells,'' said Patzert, an oceanographer with Caltech's Jet Propulsion Laboratory. ``A pattern very typical of La Nina.''

Patzert said he predicts that indeed a PDO has begun in the Pacific that could bring 10 or 20 years of a drop in average rainfall, the likes of which Southern California hasn't seen since World War II.

Ants Leetma, director of the National Weather Service Climate Prediction Center in Washington, D.C., said Southern California could be in for another dry season.

``We're at the tail end of the two-year La Nina we had,'' Leetma said. ``Pacific temps are jumping all over the place, but they're leaning on the cool side, pushing storms north.''

However, Leetma said it remains unclear whether the three-year dry season signals the longer dry period.

``There's a lot of controversy about exactly what a Pacific Decadal Oscillation is,'' he said. ``Several La Ninas could look like the start of a PDO but it's too early to tell for sure.''

Such a spell would probably have little impact on Southern California's water supply, Redmond said, because 85 percent of it comes from snowpacks in Central and Northern California's Sierra Madre range.

He said the water content of the snowpack is also off to a slightly slow start, at 55 percent of the seasonal average.

``But there's no way I would use the word drought,'' he said. ``I define that condition more on the effect that a certain precipitation level has on a certain region, and it's just not here in this case.''

Los Angeles, which relies on rainfall and local water wells for only 15 percent of its water source, is in no danger of a water shortage, according to Jerry Gewe, assistant general manager of water for the Department of Water and Power.

``We're right on target with last year at this time,'' Gewe said. ``It was dry to start with, and then it picked up and we had a wet January and February to bring us back up to a normal watershed.''

Nevertheless, Gewe said the department continues to ask businesses and the more than 4 million residents in the city to conserve water.

``Remember that we're living in a semidesert environment, and the message is always to try and conserve water.''

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Chart: SLOW START

The Los Angeles area is behind the normal rainfall total, but not as far as last season. Average rainfall for the season is 14.77 inches.

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