FORT LAUDERDALE, Fla. (Reuters)—The threat of more hurricanes than usual in the Atlantic has risen in the last month, and it promises to be "a hell of a year," a leading U.S. forecaster said Wednesday.

William Gray, the hurricane forecast pioneer who founded Colorado State University's respected storm research team, said CSU would ramp up its predictions for the 2010 Atlantic hurricane season in a report due out on June 2.

"The numbers are going to go up quite high," Mr. Gray said. "This looks like a hell of a year."

Mr. Gray, who spoke on the sidelines of a regional hurricane conference, declined to specify the number of storms CSU will forecast in its outlook next week.

In its previous forecast, released on April 7, CSU had projected the season would produce an above-average eight hurricanes, four of which could be major.

Major hurricanes pack powerful sustained winds of at least 111 mph and can go up to more than 155 mph which would be a Category 5 hurricane on the Saffir-Simpson Scale.

For instance, with winds blowing at 111 to 130 mph, Hurricane Katrina ranked as a Category 3 hurricane when it hit New Orleans in late August 2005. Katrina caused a catastrophic failure of the New Orleans levee system and is considered to be the costliest hurricane, and one of the five deadliest, in the history of the United States.

Indeed, 2005 went down as a record-breaking hurricane season after Hurricane Wilma hit in October. It was the 22nd storm, 13th hurricane, sixth major hurricane, and fourth Category 5 hurricane. Wilma's most destructive effects were felt in the Yucatan Peninsula of Mexico, Cuba and Florida. It ranks as the fourth costliest storm in U.S. history.

In its April 7 forecast, CSU also said the six-month season beginning on June 1 would likely produce 15 named tropical storms.

An average Atlantic season has about 10 tropical storms, of which six become hurricanes. Tropical storms typically pack winds of 39 to 73 mph.

Mr. Gray and Phil Klotzbach, lead forecaster with the Colorado State team, both told Reuters that forecast models showing a recent shift in wind patterns and warm tropical Atlantic waters had reinforced the likelihood that a busy hurricane season was on its way.

"Everything is setting up as a very active season," Mr. Gray said.