Gustav likely to be deadly as it heads down throat of

It happened in 2005. "Katrina went over the Loop Current and intensified rapidly," said Mark DeMaria, a Colorado-based expert on hurricane strength with the National Oceanic and Atmospheric Administration.

Then less than a month later a weak tropical storm named Rita followed Katrina into the Loop Current. Thirty hours later it was a Category 5 monster.

Both Katrina and Rita later weakened — which often happens — to Category 3 storms by landfall.

In the last several years, meteorologists have focused more attention on the Loop Current, which is only a couple of hundred miles long and not even 100 miles wide. The evidence linking it to the worst storms is beyond circumstantial, Shay said.

clipped from www.msnbc.msn.com WASHINGTON - The difference between a monster and a wimp for Gulf of Mexico hurricanes often comes down to a small patch of warm deep water that's easy to miss. It's called the Loop Current, and hurricane trackers say Gustav is headed right for it, reminiscent of Katrina. Gustav is likely to reach this current late Saturday, experts say. What happens next will be crucial, maybe deadly. The meandering Loop Current, located in the southeastern gulf, provides loads of hurricane fuel. It was a key stopover for nearly all the Gulf Coast killers of the past, including Katrina and Camille, said Florida International University professor Hugh Willoughby, former director of the government's hurricane research division.