Residents along the hurricane belt heaved a sigh of relief as the threat fizzled away for now, but scientists warned that coming years could be just as intense.

Several grim records were set during the six-month season, which officially ends on November 30.

Katrina, which killed more than 1,200 people in New Orleans and other US Gulf coast areas in August, was the most expensive US hurricane and one of the deadliest. But it was just one of a record 13 Atlantic hurricanes this year.

Hurricane Wilma, which slammed into Florida in October, became the most intense hurricane ever in the Atlantic, with its central pressure falling to 882 millibars.

In all, an unprecedented 25 tropical storms raged in the Atlantic Basin since the season started on June 1. The previous busiest Atlantic hurricane season on record was in 1933, with 21 storms.

The death and destruction the storms wrought along the Caribbean, on the shores of the Gulf of Mexico and on Florida's Atlantic coast are still evident in many areas.

In New Orleans, entire neighborhoods remain deserted, including the hardest-hit Ninth Ward which is scheduled to reopen on December 1. Friends, relatives and even insurance inspectors are still finding bodies trapped in attics and collapsed buildings.

Much of the devastation in New Orleans was caused by floodwaters after Katrina's wrath shattered levees in the famed, low-lying city.

Just as workers finished pumping out the floodwater, Hurricane Rita caused renewed flooding in the "Big Easy" in October.

That same month, Stan devastated Guatemala, even though it had weakened from a hurricane to a tropical storm by the time it hit the impoverished central American nation. Flashfloods and mudslides left about 2,000 people feared dead, destroyed crops, killed cattle and cut off an entire province.

Last year's Atlantic season already had been particularly busy and damaging, and forecasters believe this is part of period of intense hurricane activity in the Atlantic Basin.

Several experts say the hyperactivity is likely to continue for several years, as part of what they see as a historic cycle where busy hurricane periods alternate with decades of relative calm.

"In the 1970's, there was an average of about 10 Category four and five hurricanes per year globally. Since 1990, the number of Category four and five hurricanes has almost doubled, averaging 18 per year globally," said Peter Webster, an expert at the Georgia Institute of Technology.

Hurricanes that rank at category four on the Saffir-Simpson intensity scale have sustained winds of between 210 and 249 kilometers (131 to 155 miles) per hour, and category five -- the highest -- has winds of above 249 kilometers (155 miles) per hour.

There are strong fears that global warming caused by emissions of greenhouse gasses is further fueling the deadly weather systems by increasing sea surface temperatures, though the theory remains controversial.

While experts disagree on whether global warming is to blame for more frequent and more intense hurricanes, most agree the risk posed by the deadly storms increases as US coastal areas become more densely populated.

"The large upward surge in hurricane damage in the US, is clearly owing to the confluence of rapidly increasing coastal population with a decadal time-scale upswing in Atlantic hurricane activity," said Kerry Emanuel, a professor of atmospheric science at the Massachussetts Institute of Technology.

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