At 03Z last night, Gustav was downgraded to a Tropical Storm, and is still at that status, as it passes over the high mountainous terrain of Haiti's southwestern peninsula. And it's doing so very slowly (~4kts). The flash flooding there must be terrible.
An AP report from Haiti states "rising water was threatening crops in Haiti, already a powder keg because of spiking food prices. Earlier this year, there were deadly protests over the high cost of food. Gustav lingered over the nation's impoverished and deforested southern peninsula, threatening banana and vegetable fields. Residents in coastal Les Cayes ignored government warnings to seek shelter, instead throwing rocks in protest of Haiti's poor economic conditions". Not a good situation. And now Gustav is eyeing up Cuba, Jamaica, and the Cayman Islands.
The western tip of Cuba could have a brush with an intense Gustav on Saturday, then the storm enters the central Gulf of Mexico, where it's forecast to gradually start turning toward the NW. Presently, Louisiana is a likely target on Monday, but the situation will of course be very carefully watched and forecasts will be tweaked.
The HWRF model (WRF model that's coded to specialize in hurricanes) has the following forecast out to 5 days (the fields shown in the large plot are sea level pressure in the line contours and vorticity in the shaded contours... and in the zoomed plot are sea level pressure in the line contours and surface wind speed in the shaded contours):
HWRF shows a peak intensity of 901mb and 135kts late this weekend, and a major landfall very similar to that of Camille and Katrina. The official NHC forecast currently agrees very well with this scenario, but it's still 5-6 days out.
The easterly wave that was near 20N 56W yesterday has barely moved and is now near 20N 57W. It's estimated at 25kts and 1009mb, and although vertical shear has made development a challenge these past few days, it is forecast to lessen and allow this system to get better organized. The one near the Cape Verdes is lacking organized convection now, but will still be watched closely. This is the time of year when a lot can happen at once!
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