WASHINGTON—Hurricane Rita, following in Katrina's wake, zipped from a tropical storm to a Category 5 hurricane in 30 hours—the storm equivalent of a racecar going 0 to 100 in nothing flat.
That's because Rita and Katrina both found the perfect hurricane fuel—ultra-deep, super-warm water—and then lingered there, storm researchers said.
The result: For the first time in one hurricane season, two Category 5 hurricanes powered across the Gulf of Mexico toward the U.S. coast.
Both storms hit what scientists call the Loop Current, an annual 100-mile swath of 82-degree water between the Florida Keys and the mouth of the Mississippi River that's 300 feet deep, said Frank Marks, the director of the Hurricane Research Division of the National Oceanic and Atmospheric Administration.
Normally, warm water is about 125 feet deep.
That deep pool of warm water "is enough to make a really nasty hurricane," said Hugh Willoughby, senior hurricane scientist at Florida International University.
Most of the time, hurricanes cross the loop, intensify somewhat, then get back to cooler waters where they weaken.
But both Katrina and Rita "are going straight down the slot like a barrel of a shotgun," Marks said.
Adding to the storms' intensity is the absence of high altitude winds, which would have weakened them.
The effect of the warm Gulf waters was predictable. But Katrina left a mystery in its wake.
As Katrina passed over an eddy of the Loop Current in late August, it should have cooled the water by about 5 degrees Fahrenheit. It didn't and that surprised scientists.
Rita is predicted to hit the same eddy on Thursday afternoon.
NOAA's buoys and thermometers are waiting.
(c) 2005, Knight Ridder/Tribune Information Services.
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