2008 Hurricane Season Will Be "Well Above Average"

Willie Drye
for National Geographic News
April 9, 2008
Four major hurricanes, including one with a good chance of hitting the United States, will form in the Atlantic Ocean during the upcoming hurricane season, experts said today.

Hurricane forecasters at Colorado State University (CSU) predict a "well above average" 2008 hurricane season, with 15 named tropical storms gathering between June 1 and November 30.

Long-term yearly averages are nine or ten named storms, six hurricanes, and two intense hurricanes per year.

Eight of the 2008 storms are expected to intensify into hurricanes, which are defined as having winds of at least 74 miles (119 kilometers) an hour.

(See photos of hurricanes and the destruction that follows.)

East Coast Landfall

There is a 70 percent likelihood that a major hurricane will make landfall somewhere on the U.S. East Coast during the coming season, CSU forecasters William Gray and Phil Klotzbach said.

The forecasters did not speculate about where the hurricane is likely to come ashore.

Over the past hundred years, the likelihood of the East Coast being hit by a major hurricane has been about 50 percent.

Gray, who has been issuing long-range hurricane forecasts for decades, told National Geographic News that the summer of 2008 will continue a trend of above-average hurricane seasons that started in 1995.

The stormier summers have been due to ocean currents that cause an increase in the Atlantic's salt content, which in turn causes an increase in water temperature.

The fluctuations are cyclical, with warming and cooling cycles typically lasting about 30 years.

Gray acknowledged, however, that CSU forecasters "haven't done too well with our forecasts for the last couple of seasons."

(Read about last year's off-target forecasts.)

Gray and Klotzbach predicted 17 named storms for the 2007 season, but only 14 formed. A 15th tropical storm formed in May 2007, several weeks before the official start of the season.

The less-than-expected activity last year was caused by a high-pressure system that formed off the East Coast late in the season, Gray added.

CSU and other forecasters will be issuing updated forecasts starting on June 3.

Big "If"

Meteorologist Joe Bastardi of AccuWeather said he predicts 12 or 13 tropical storms will form and produce three or four hurricanes and one major hurricane.

That's fewer storms than the CSU forecasters predict but still above-average activity, Bastardi said.

Keith Blackwell is a meteorologist at the Coastal Weather Research Center at the University of South Alabama in Mobile.

He sees important indications that the summer of 2008 could be stormier than last year, he told National Geographic News.

Blackwell noted that water temperatures are well above normal for this time of year off Cape Verde on the west coast of Africa.

Hurricanes draw their energy from warm ocean water, and some of the worst hurricanes in history have started as storms off Cape Verde.

Other conditions are also in place that could reduce the upper-level winds over the Atlantic, which can prevent a hurricane from strengthening.

"It does look like it's shaping up for an active season, if these features remain in place for the next few months," Blackwell said.

"But that's a big 'if.'"

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