The CSU forecast, unchanged from the team's prediction issued on April 4, fell roughly in line with other forecasts for the hurricane season, which runs from June 1 to Nov. 30.

The National Oceanic and Atmospheric Administration, the US government's climate agency, said last week it expected 13 to 16 tropical storms, with eight to 10 hurricanes and four to six major hurricanes.

Gray's prediction and those of other forecasters were wildly off the mark last year, which saw a record-shattering 28 storms, including 15 hurricanes. Seven of last year's were major storms of Category 3 or higher on the five-step Saffir-Simpson scale of intensity.

Those hurricanes included Katrina, the costliest natural disaster in US history. It killed about 1,300 people and caused more than US$75 billion in damage when it burst the levees in New Orleans, swamping the historic jazz city and displacing hundreds of thousands of residents.

Hurricane Wilma, which struck Mexico and Florida, was at one point in its life the strongest hurricane ever recorded in the Atlantic-Caribbean basin.

Gray's team said warm water in the Atlantic Ocean coupled with a neutral El Nino -- a warm water phenomenon in the eastern Pacific that can dampen Atlantic hurricane activity when it is strong -- foreshadow a season well-above the long-term average of 10 storms and six hurricanes.

"If the atmosphere and the ocean behave as they have in the past, we should have a very active season, but that doesn't necessarily translate into storms that produce as much destruction as last year," Gray said in a statement.

His team's forecast predicted an 82-percent chance that at least one major hurricane of Category 3 or higher will hit the US coast, compared to a long-term average probability of 52 percent.

The US East Coast has a 69 percent chance of being struck by a big storm, compared to 31 percent on average, while the Gulf Coast, the heartland of the US oil and gas industry, has a 38 percent chance, compared to 30 percent long term, the forecast said.

The circular tropical weather systems that develop into hurricanes become tropical storms when their sustained winds reach 39 mph (63 kph). At 74 mph (119 kph) they become hurricanes.

The CSU team said total cyclone activity in the Atlantic and Caribbean -- tropical storms and hurricanes are cyclones -- is expected to be 195 percent of the average season, compared to 275 percent last year.

Scientists believe the Atlantic is about 11 years into a period of enhanced hurricane activity that could last another 20 years or more. Some researchers say there are indications that human-caused greenhouse gases help increase the intensity of hurricanes, which draw energy from warm water.