Noted hurricane prognosticator William Gray struck a familiar chord Tuesday, issuing an updated forecast that echoed his previous 2008 prediction for eight hurricanes, four Category 3 or higher.

Gray's team at Colorado State University predicted a total of 15 named storms, the same that they called for in April.

A warm Atlantic Ocean was the reason Gray's team thinks this year will be worse than an average season.

"Conditions in the tropical Atlantic look quite favorable for an active hurricane season," said Phil Klotzbach, Gray's research partner and the forecast's lead author. "Sea-surface temperatures are unusually warm, while sea-level pressures and levels of vertical wind shear are quite low."

There are typically fewer hurricanes when vertical wind shear is high, because the winds break up storms as they form.

The planet is on the tail end of a La Nina, a trend of cooling in the Pacific near the equator, which tends to trigger above-normal hurricane seasons. El Nino, the opposite pattern, usually suppresses hurricanes by creating more trade winds that shear tropical storms apart as they form.

"At this point, we do not believe that an El Nino will develop by late this summer; however, this is a possibility that must be monitored closely," Klotzbach said.

Hurricane season runs June 1 to Nov. 30. Storms get named when winds reach 40 mph.

A typical season has 10 named storms, six hurricanes and two major hurricanes, Klotzbach said.

A separate forecast, issued by the National Oceanic and Atmospheric Administration last month, called for a 65% chance of a busier-than-average hurricane season this year, with two to five Category 3 hurricanes — winds of 111 mph or greater — developing in the Atlantic.

NOAA predicted 12 to 16 named storms and six to nine hurricanes.

Critics of Gray's forecasts argue insurance companies can point to them as reason to increase rates. His forecasts are partially supported by Lexington Insurance Company, one of the world's leading property and casualty insurance organizations and a member of the American International Group, which reported $14 billion in net income last year.

The forecasts also are supported by other organizations, including the National Science Foundation.

Klotzbach devised a new computer statistical model after his team overestimated the last two hurricane seasons.

In both 2006 and 2007, the Colorado State researchers believed 17 named storms, nine hurricanes and five major hurricanes would form.

NOAA also predicted busier-than-average hurricane seasons in 2006 and 2007.

Instead, the actual 2006 tallies were nine named storms, five hurricanes and two major hurricanes. The 2007 counts: 14, six and two, respectively.

The 2005 hurricane season, which included Katrina, was so active it exceeded NOAA's listing of 21 names.

Gray said in April that the Atlantic basin is in the midst of a natural active hurricane cycle that likely will last another 15 to 20 years.

Klotzbach warned that coastal residents need to prepare for every hurricane season, regardless of seasonal predictions.

"There is inherent uncertainty in seasonal predictions," he said. "Also, seasonal forecasts cannot say anything about when or where storms are going to make landfall."

Predicting whether, where or when any of the storms may hit land is the job of the National Hurricane Center after a storm forms.

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