FAIRHOPE, Ala. — Fans of El Niño may soon be bidding it adieu. Forecasters with Colorado State University’s Tropical Meteorology Project predict the weather system that kept the 2009 Atlantic Hurricane Season quieter than had been the case in recent years will dissipate this coming spring, opening the door to the possibility of a greater number of tropical storms and hurricanes.

“When we’ve gone back and looked at historical data from 1950-1969 and from 1995 to the present, we’ve seen that the warm (sea surface) temperatures in the Atlantic typically make El Niño one-year events,” said Dr. Philip Klotzbach, lead author of the early extended-range forecast issued Wednesday, Dec. 9. “All seven (in the elevated period of activity) went to neutral or cool.”

Klotzbach said as El Niño fades, neutral conditions could even shift to La Niña, a sister phenomenon that could greatly strengthen the conditions needed for successful hurricane development and sustainability.

He and forecast co-author Dr. William Gray are calling for above-average activity in the Atlantic basin. The CSU team expects 11-16 named storms, 6-8 hurricanes and 3-5 major hurricanes (Saffir/Simpson Scale category 3 though 5), with sustained winds of 111 mph or more.

This is the first time in its 27 years of such predictions that the team is using a range of possibilities in its December early season forecast.

Klotzbach said, “I thought since it’s seven months prior to the hurricane season, we needed a range because these early forecasts typically have less accuracy.” He pointed out that conditions in the Atlantic can change substantially before the June 1 start of the hurricane season.

“The Atlantic basin has the largest year-to-year variability of any of the global tropical cyclone basins,” he noted. “Our early December statistical forecast methodology shows evidence over 58 past years that significant improvement over climatology can be attained. Closer to the season, we will know more about how the conditions will change.”

The statistical model used to make the projections takes into account a three-predictor scheme that correctly forecast above- or below-average seasons in 44 out of 58 years.

The hurricane team’s forecasts are based on the premise that global oceanic and atmospheric conditions — such as El Niño and tropical Atlantic sea surface temperatures — that preceded active or inactive hurricane seasons in the past provide meaningful information about similar trends in future seasons.

For the 2010 Atlantic basin hurricane season, the CSU hurricane forecast team also predicts a 64 percent chance that at least one major hurricane will make landfall on the U.S. coastline in 2010. The long-term average probability is 52 percent.

For the Gulf Coast, from the Florida panhandle westward to Brownsville, Texas, the probability of a major hurricane making landfall is 40 percent (the long-term average is 30 percent). The U.S. East Coast chances, including the Florida peninsula, is 40 percent (the long-term average is 31 percent), and the probability of a major hurricane making landfall in the Caribbean is 53 percent (average for the last century is 42 percent).

CSU forecasters will list more specific numerical forecasts for the 2010 hurricane season beginning with their April 7 forecast. The Atlantic Hurricane Season runs through Nov. 30.

Klotzbach cautions, however, that the season was set by man and nature sometimes doesn’t heed such boundaries.

“With (Hurricane) Ida, even I thought the season was over,” he said. “Fortunately it experienced significant shear. It really stayed together a lot better than the National Hurricane Center first thought, and they updated their forecasts. It was the second latest landfalling storm on record.”