Gustav is now a Category 1 hurricane with top sustained winds of 90 mph and a direct threat to Haiti. But forecasters at the National Hurricane Center warn this morning that the storm will soon be moving over very warm waters, and "most indications are that Gustav will be an extremely dangerous hurricane in the northwestern Caribbean Sea in a few days."

Here is the current advisory. And here is the view from space. 

The current forecast track sends Gustav into the Gulf of Mexico by Sunday morning. Surface waters there are a bit cooler than those south of Cuba. But they are warm enough at this time of year, and conditions are sufficient to warrant concern. 

Gustav - the seventh named storm of the 2008 Atlantic season - became stronger still over night after growing yesterday from a tropical distubance, to a tropical depression, tropical storm and finally a hurricane all in one day.  

The storm's center was about 75 miles south southeast of Port au Prince, Haiti this morning, moving toward the northwest at about 9 mph. Hurricane warnings were posted for the southern portions of the Dominican Republic and Haiti.

A ridge of high pressure to the north was expected to steer the storm more toward the west for the next few days.  A hurricane watch is posted for southeastern Cuba, including the U.S. military outpost at Guantanamo Bay, Cuba. The storm was expected to pass just south of Guantanamo on Wednesday.

Top sustained winds were forecast to reach Category 2 strength (top sustained winds 96 mph) later today before making landfall in southwestern Haiti. residents of that region were told to expect rainfall of 4 to 7 inches, with some spots receiving up to 15 inches. Storm surges of 2 to 4 feet above normal tides were anticipated.

After leaving Haiti, forecasters said, Gustav "is forecast to be over extremely warm waters with relatively light shear. The official intensity is increased and now calls for Gustav to be a major hurricane [Category 3 or higher, top sustained winds of 111 mph or higher] in the northwest Caribbean Sea. It is worth noting that [two computer models] ... show an even stronger hurricane."

If Gustav moves on into the central Gulf of Mexico, it will become a threat to offshore oil operations. That would surely have an impact on the oil markets. At that point, the storm, while it could well weaken, would almost inevitably make landfall somewhere along the U.S. Gulf Coast. Once in the Gulf, there is no way out for these storms except to crash ashore. 

In the meantime, forecasters are also watching two other Atlantic disturbances that could become more developed in the coming days.