WSI Corp. predicted 13 tropical storms in the 2009 season and said seven would develop into hurricanes. The long-term average during the six-month season is for 10 or 11 tropical storms and six hurricanes.

WSI, based in Andover, Massachusetts, forecast that three of next year's hurricanes would be dangerous storms with a rank of Category 3 or above on the five-step Saffir-Simpson scale of hurricane intensity. Such storms feature sustained winds of at least 111 miles per hour.

The WSI forecast was in line with one issued on December 10 by the prominent team of U.S.-based researchers at Colorado State University, formed by forecasting pioneer William Gray. The Colorado State team, whose forecasts are followed closely by energy and commodity traders, said 2009 would see 14 tropical storms, seven of which would develop into hurricanes.

Like WSI, Gray's team said three of next year's hurricanes would pack winds hitting Category 3 or above.

The 2008 season, which ended on November 30, was one of the most active on record and produced 16 tropical storms, eight of which became hurricanes. According to the U.S. National Oceanic and Atmospheric Administration, it spawned a record number of consecutive storms that struck the United States.

"Since 1995, most tropical seasons have been more active than long-term averages, due to warmer Atlantic Ocean temperatures," WSI forecaster Todd Crawford said in a statement. "We do not see any reason why this active regime will not continue in 2009."