UPDATE 2-U.S. forecaster raises Atlantic hurricane number

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By Michael Christie

MIAMI, April 9 (Reuters) - The noted Colorado State University hurricane research team on Wednesday raised the number of tropical storms and hurricanes it expects to form in the upcoming Atlantic storm season.

The team founded by forecasting pioneer Bill Gray increased its outlook by two tropical storms to 15, and by one hurricane to eight, compared with a long-term average of around 10 and six, respectively, for a storm season.

"Current oceanic and atmospheric trends indicate that we will likely have an active Atlantic basin hurricane season," said Gray in a statement.

Of the eight hurricanes predicted by the forecasters for the six-month season starting June 1, four were forecast to become major storms with winds of at least 111 miles per hour (178 kph). Major, or intense, storms, which rank from Category 3 to Category 5 on the five-step Saffir-Simpson scale of hurricane intensity, are the most destructive.

"Based on our latest forecast, the probability of a major hurricane making landfall along the U.S. coastline is 69 percent compared with the last-century average of 52 percent," said Gray protege Phil Klotzbach, who now leads the CSU team.

"We are calling for a very active hurricane season this year, but not as active as the 2004 and 2005 seasons."

The United States was struck by just one minor hurricane in the 2007 Atlantic storm season and escaped unscathed the year before.