Weather Nerd

Gustav weakens to T.S. -- but 125 mph winds by Friday?

As expected, Hurricane Gustav has been downgraded to a Tropical Storm as of 11pm EDT due to land interaction with Haiti. Yet the long-term prognosis remains grim. Indeed, the latest NHC forecast now brings Gustav to the threshold of Category 4 hurricane status by Friday — with 125 mph winds — as it approaches the Gulf of Mexico. Needless to say, that’s a scary scenario.

Gustav’s eventual mainland landfall target remains entirely up in the air, though the Houston Chronicle‘s Eric Berger points out that the important GFDL model, which previously seemed to be eyeballing New Orleans, now envisions a threat to Houston/Galveston. But again, it’s much too early to say.

At the same time, Alan Sullivan sees the potential for a paradigm-shifting encounter with Cuba:

If Gustav turns enough to the left — most models still say it will — then the core will stay just offshore of SE Cuba and redevelop. If the steering current forces Gustav over the mountains of Cuba, it will weaken further before reaching water again. On that course, Gustav would only be a depression when it emerged into the Florida Straits or southeastern Gulf of Mexico. It would be a long time regaining strength. This is a totally different scenario from a cat 4 storm roaring through Yucatan Channel. We’ll know more tomorrow.

Indeed. The next 24 to 36 hours are crucial to Gustav’s future. Stay tuned.