SANTIAGO (Reuters) - After five years of drought in central Chile, there is a good chance that the El Niño weather pattern could bring much-needed rains during the Southern Hemisphere's winter, the national meteorological service said on Thursday.

In recent years, power producers in the world's top copper producer have been forced to rely on more-expensive fossil fuels as the lack of rain has dented hydroelectric generation.

Over 40 percent of installed capacity in Chile's central power grid, which supplies electricity to nine out of every 10 residents, is in hydrogeneration.

Meanwhile, water levels in reservoirs in some parts of the country have been falling rapidly, threatening fresh fruit production, especially for smaller-scale operations.

Fruit and wine are among Chile's largest exports after copper, with total exports of $6.1 billion in 2012, according to government figures.

There is a 50 percent chance that El Niño could bring above-average precipitation in August, the middle of Chile's winter season, especially in the central and southern regions, the weather service said.

Normal rain conditions are seen in Chile during autumn.

El Niño occurs, on average, every three to five years, according to the U.S. National Oceanic and Atmospheric Administration, and is characterized by a warming of surface temperatures in the Pacific Ocean. It can trigger droughts in some places and floods in others.

El Niño will likely hit Peru with a "weak to moderate" intensity starting in April, affecting the fishmeal industry on the country's northern coast, Peru's government said on Wednesday.

Chile, whose territory is roughly as long as the distance from New York to San Francisco, has the world's driest desert in the north and temperate rainforests in some part of the south.

The 2004-13 was the driest 10-year period in nearly the last 150 years, the meteorological service said.

(Reporting by Anthony Esposito)