The El Niño phenomenon, which some forecasters say already has returned, could bring an early end to one of the toughest hurricane seasons in Florida's history.

But an El Niño season may bring little help to storm-ravaged farmers in the Sunshine State, and could bring bad news to people in other parts of the country, a University of Florida (UF) researcher says.

"There's no doubt that an early end to the hurricane season would be good for Florida," said Jim Jones, a distinguished professor of agricultural and biological engineering at UF's Institute of Food and Agricultural Sciences. "But for farmers growing winter crops, the wet weather associated with El Niño would probably encourage crop disease and limit the amount of sunlight during the growing season, cutting crop production."

El Niño is a periodic warming of Pacific Ocean temperatures that can cause global changes in weather patterns. Typically occurring every two to seven years, an El Niño warming can cause a shift in the jet stream over North America, bringing cooler, wetter weather to southeastern United States during fall and winter months - and providing shearing winds that rip hurricanes apart before they hit the U.S. coastline.

Jones tracks the effects of El Niño on Florida agriculture. He is a member of the Southeastern Climate Consortium, a coalition of university researchers dedicated to predicting seasonal climate conditions. While most weather forecasts tell people about the conditions they'll face in the next few days, the consortium's mission is to give the public a general picture of temperature, rainfall and other climate conditions over a three- to six-months period. The group includes researchers from UF, Florida State University, the University of Miami, the University of Georgia, Auburn University and the University of Alabama-Huntsville.

Warm temperatures in the eastern Pacific Ocean led the National Oceanic and Atmospheric Administration to declare, on Sept. 10, that El Niño has returned. While the NOAA forecast calls for a weak El Niño phenomenon, and cautions that weather effects are still not clear, some forecasters have predicted that the return of El Niño could shut down hurricane activity in the Atlantic as early as October, a month or more before the hurricane season typically ends.

Consortium forecasters still give El Niño only a 50-50 chance of returning in a way that would affect this year's weather.

"The Pacific Ocean temperatures put us on the borderline of an El Niño event right now," said David Zierden , an assistant state climatologist, who does climate prediction for the consortium. "Based on the storm activity we're seeing in the Atlantic, I'm not sure this will come on strong enough to affect the hurricane season."

An El Niño winter may hold little good news for Florida farmers already devastated by hurricanes Charley and Frances, said Jones, who tracks the effects of El Niño and other climate trends on agriculture.

El Niño typical makes Florida's winters wetter and cooler than average, Jones said. While the average resident may not notice the change in weather, he said, that change can have a major impact on farmers, who rely on the state's mild winters to supply the country with much of its winter vegetable crop.

"Plants like the same conditions that the tourists do - sunshine and warm temperatures. With cooler temperatures and overcast skies, you see slightly slower development of crops and less photosynthesis, which can have an effect on total production," Jones said. "For example, we've historically seen South Florida tomato yields drop 10 to 15 percent during an El Niño year."

Wetter weather also can encourage growth of bacteria and fungi that cause crop diseases, Jones said.

The winter vegetable growing season already has been shortened by the hurricane season. Agents of UF's Cooperative Extension Service say many vegetable farmers were forced to delay planting of their winter crops, which normally would have been planted around the time Hurricane Frances arrived.

"Growers were just getting ready to plant as Frances hit," said Laura Powell, a UF extension agent in Palm Beach County. "They'd already made beds for the plants and fumigated the fields. Now they're repairing damage, and when it comes to planting, they may be far behind schedule."

An El Niño year also could have ill effects in other parts of the country, Jones said. El Niño typically brings extremely dry weather to the Pacific Northwest, he said, increasing the risk of wildfire. Southern California, like Florida, would be cooler and wetter, he said.

"If El Niño kicks in, you won't be hearing about wildfires in Southern California - you'll be hearing about mudslides," Jones said.

While it's usually impossible to forecast an El Niño event more than a few months in advance, the consortium and other organizations are trying to develop climate models that would offer better forecasts over a longer range. Accurate climate prediction, Jones said, could reduce one of the biggest economic risks faced by farmers.

"A bad growing season puts a big economic burden on a grower," Jones said. "If you know in advance that this year's climate won't be good for a certain crop, you can scale back your planting of that crop, or change practices, and cut your losses."