Expect busy 2011 hurricane season, CSU team says

The windows of Cranberry Real Estate are boarded up and marked with a message to the looming storm in West Dennis, Massachusetts on Cape Cod, September 3, 2010.

MIAMI (Reuters) - The 2011 Atlantic hurricane season will be nearly as busy as the one that just ended, Colorado State University meteorologists predicted on Wednesday.

The forecasting team anticipates 17 tropical storms, with nine of those strengthening into hurricanes during the season that runs from June 1 to November 30.

Five will grow into "major" hurricanes of category 3 or higher on the five-step Saffir-Simpson scale of hurricane intensity, with sustained winds of at least 111 mph (178 km per hour), the team predicted.

That compares with 19 tropical storms, 12 hurricanes and five major hurricanes during the 2010 season that just ended on November 30. The 2020 season tied with 1887 and 1995 for the third-highest storm total on record.

An average season brings 11 storms, six hurricanes and two major hurricanes in the Atlantic, Caribbean and Gulf of Mexico.

The forecasters said sea surface temperatures in the North Atlantic were still at record warm levels, indicating the region is still in a multi-decade period of high activity for hurricanes.

They said it also seemed unlikely that El Nino would develop. El Nino is a warming of the tropical Pacific that produces wind patterns that squelch development of tropical storms in the Atlantic.

"This could mean a more active hurricane season," said Philip Klotzbach, who heads the Colorado State University team with pioneering forecaster William Gray.

There is a great deal of uncertainty in forecasts issued so far in advance but meteorologists have become more effective at analyzing large-scale patterns and predicting whether the next season will be busy, average or calmer than average.

That can be useful in long-range planning for industries affected by hurricanes, including insurers, farmers and offshore energy operations.

But short-term weather patterns dictate where any individual storm will go and no one foresaw that dry air masses and the jet stream wind current would combine to push last year's storms away from the United States.

"The U.S. was extremely lucky in 2010 in that none of the 12 Atlantic basin hurricanes that formed crossed the U.S. coastline," Klotzbach said.

"On average, about one in four Atlantic basin hurricanes makes U.S. landfall, and therefore, we would expect to see more landfalling hurricanes in 2011.

(Reporting by Jane Sutton, editing by Philip Barbara)