“We expect current moderate El Nino conditions to transition to neutral conditions by this year's hurricane season,” Klotzbach said, in a statement. “The dissipating El Nino, along with the expected anomalously warm Atlantic ocean sea surface temperatures, will lead to favorable dynamic and thermodynamic conditions for hurricane formation and intensification.”

Gray said 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. While patterns may change before the start of hurricane season, we believe current conditions warrant concern for an above-average season.”

The team added that current weather conditions have a number of similarities to early April conditions that preceded the hurricane years of 1958, 1966, 1969, 1998 and 2005. All five of these seasons had above-average activity, especially the seasons of 1969, 1998 and 2005.

According to the Insurance Information Institute, Hurricane Katrina, which occurred in 2005, was listed as the most expensive catastrophe loss in the United States in terms of insured loss at more than $45 billion in 2008 dollars.

Both Klotzbach and Gray predict the 2010 season will have slightly less activity than the average of these five earlier years. The duo predicts tropical cyclone activity in 2010 will be 160 percent of the average season. By comparison, 2009 witnessed tropical cyclone activity that was about 70 percent of the average season.