The waters in the Gulf aren't that warm. They are only in the 80's that in itself will limit the size of Gustav and probably be very limiting on hurricanes later in the season.
I wasn't talking about the whole Gulf, I was referring to eddies from the loop current that runs up through the Yucatan Channel. The loop current goes into the GoM and then east toward Florida where it is called the Florida Current.
The loop current is very warm, much warmer than the rest of the GoM water.
Every now and then it sheds an eddie that spins off in the opposite direction of the current flow and goes towards Texas or Louisiana.
You can read about the loop current here
http://ams.allenpress.com/perlserv/?request=get-document&doi=10.1175%2F1520-0485(1999)029%3C1180:LCEPIT%3E2.0.CO%3B2&ct=1&SESSID=3104b4c832f8bed86fde1d682ff65206
What happens when an eddie occurs during hurricane season and a storm passes right over the eddie is that the extremely warm waters are like a supercharger for the 'cane. From Wikipedia:
An example of how deep warm water, including the Loop Current, can allow a hurricane to strengthen, if other conditions are also favorable, is Hurricane Camille, which made landfall on the Mississippi Gulf Coast in August of 1969. Camille formed in the deep warm waters of the Caribbean, which enabled it to rapidly intensify into a Category 3 hurricane in one day. It rounded the western tip of Cuba, and its path took it directly over the Loop Current, all the way north towards the coast, during which time the rapid intensification continued. Camille became a Category 5 hurricane, with an intensity rarely seen, and extremely high winds that were maintained until landfall (190 mph / 305 km/h sustained winds were estimated to have occurred in a very small area to the right of the eye).
You can read more at wikipedia and see how the eddie, or the loop current itself, strengthened Katrina, Rita, Wilma, Andrew and Opal.
Loop Current - Wikipedia, the free encyclopedia
If Gustav comes up the Yucatan Channel he will be riding the Loop Current and growing. If he continues toward Texas and Louisiana, he will encounter at least the eddie that was spun off in July, and he may also encounter an older one closer to the Texas coast.
My uncle rode Camille out about 30 miles north of the coast in Mississippi. He was a Civil Defense official and when we moved there the next year he took us on a tour and told us stories. This was a guy who fought his way out of the Chosin Reservoir, and I still remember what he said about Camille: "I'll never stay again for a storm that big."
I left for Rita - along with a couple of million other people. That's an experience I don't want to duplicate, and if I leave for another storm in the future it will be with a great deal of hesitation. But two things influenced that decision. I went to the New Orleans area a few days after Katrina and helped out some hard-pressed police, and I had access to the damage estimates that were being projected for my suburb that was, at one point, right in the path of Rita when she was a 5. I'm fairly certain my house wouldn't stand up very well to a 140 MPH wind. Rita was more intense than Katrina, and had gusts of almost 240 MPH. Luckily for a lot of people she turned toward a less inhabited area and weakened down to a 3. Even then she caused $11 billion in damage.
I've worked outside in a direct hit category 3 before. That was interesting but not too scary. If I didn't have to be outside I would definitely stay indoors. But a Cat 5 coming right at me gets my respect.
I got stuck in a gas line a few weeks ago when some little hurricane was wandering around offshore (Dolly?). The only reason I was there was because I was on "E". I had a good laugh at all the people freaking out at the last minute, Dolly didn't concern me at all. But Gustav has my attention - he has potential.