Atlantic hurricane activity will probably be high in 2007, bringing more than the average number of storms to the region and more systems making landfall in the U.S. than in a typical year, U.K.-based forecasters said.

There is a 79 percent chance that hurricane activity in 2007 will be above average and a 76 percent chance of more than the typical number of storms hitting the U.S., Tropical Storm Risk, a group of insurers and forecasters, said in an online statement.

Trade winds probably will be weaker than normal and ocean temperatures higher than usual, ``conditions which both favor an above-average hurricane season,'' the group said on its Web site.

The scientists predicted 16 named storms in the Atlantic in 2007. Nine of them will become hurricanes, and four of those will be intense hurricanes, they predicted. Three tropical storms and two hurricanes were forecast to hit the U.S. Tropical storms have sustained winds of at least 39 miles (63 kilometers) per hour and are assigned names. They become hurricanes at 74 mph.

The prediction for 2007 follows a season that was milder than indicated by the forecasts from Tropical Storm Risk and from Colorado State University, whose hurricane predictions are closely watched by insurers and local governments.

On average, 10.6 named storms and 5.9 hurricanes were recorded annually in the Atlantic basin during the 1965-2004 period, according to the U.S. National Oceanic and Atmospheric Administration.

After accurate forecasts for the 2003-5 seasons, TSR said a year ago that the 2006 season would yield 16 tropical storms in the Atlantic basin. Eight were predicted to become hurricanes, with four of those growing into ``major'' systems rated Category 3 or above on the five-step Saffir-Simpson scale of intensity. The Colorado forecasters predicted nine hurricanes, five of them major, with winds of 111 mph.

El Nino

Nine tropical storms formed in the Atlantic during this year's June 1 to Nov. 30 season, including five that became hurricanes -- two of them rated a Category 3 or above.

The Colorado scientists, William Gray and Philip Klotzbach, on Oct. 3 said that while the greatest hurricane danger for the 2006 Atlantic season was over, two more tropical storms were likely to form. None has materialized.

Gray and Klotzbach attributed the change in storm threat to a developing weather pattern known as El Nino, which occurs every two to seven years and changes weather around the world. The pattern is caused by a warming of the equatorial waters in the Pacific Ocean. The U.K. scientists also said the accuracy of their forecasts this year had been reduced by El Nino.

`No Precedent'

``The below-average 2006 hurricane season was due to the presence of considerable African dry air and Saharan dust during August and September, which inhibited thunderstorm occurrence and therefore tropical storm development, and to the unexpected onset of El Nino conditions from mid-September,'' Mark Saunders, TSR's lead scientist, said on the Web site yesterday. ``There is no precedent for these factors together having been so influential before.''

Tropical storms may form before and after the six-month hurricane season. In 2005, the last named storm of a record season, Zeta, formed on Dec. 30. That season's 27 named storms eclipsed the previous record of 21 in 1933, and its 15 hurricanes beat the tally of 12 from 1969. The worst was Hurricane Katrina, which devastated New Orleans and much of the U.S. Gulf Coast in August 2005.

Tropical Storm Risk, founded in 2000, includes climate scientists and statisticians from University College London and the Met Office, the U.K. government's forecasting arm. TSR is sponsored by Benfield Group Plc, a U.K. reinsurance broker; Royal & Sun Alliance Insurance Group Plc, Britain's second-largest non- life insurer; and Crawford & Co., which helps manage claims for insurance companies.

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By Alex Morales
Bloomberg News

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