From Jonathan Vigh:
The 9th Tropical Depression of the season formed this afternoon a few hundred miles southwest of the Cape Verde Islands. This system came off Africa a couple days ago and has possessed deep convection for at least the last 36 h. Healthy outflow was spreading out in all directions even before the system received a number, and it appears to be in low shear. Its relatively low latitude and a lack of any immediate troughs will allow this system to traverse the Atlantic fairly undisturbed for the next 5 days. The official forecast calls for a 70 kt hurricane near Barbados in 5 days. At 21Z, Tropical Depression 9 was at 9.7N 29.1W, moving towards the west at 17 kt, with winds of 25 kt and an estimated central pressure of 1009 mb. Meanwhile, Hurricane Francis is currently rampaging through the Bahamas and targeting the central Florida east coast. The storm's southern eyewall passed a little to the north Grand Turk Island in the middle of the night. Sustained winds were clocked at 79 mph, which caused damage to roofs trees. An hour or two ago, the eye passed directly over the small, but populated island of San Salvador. Winds rapidly climbed to a sustained 114 mph (with higher gusts). Long Island is next, followed by Cat Island and Eleuthera (this island was strongly affected by Hurricane Andrew in 1992). Unfortunately, nearly all the Bahaman Islands will be affected by this storm. About 300,000 people live in the Bahamas, and nearly all of them are going to experience some portion of this storm (it is hard to evacuate from an island for obvious reasons). Frances weakened somewhat this morning, with the central pressure rising to 949 mb. Winds have decreased slightly to 120 kt. There was an apparent disruption to the eye, which was open for a while this morning. Perhaps this was another eyewall cycle, or even a bit of vertical wind shear. The appearance on satellite is not quite as good as in recent days -- the storm is a little ragged and somewhat asymmetrical, but very deep convection is still blowing up in the eyewall. With continuing low shear, extremely warm Gulf Stream waters (as warm as 88 deg F along the coast!), and less dry air in the environment, there is at least a chance the storm will strengthen before landfall. More eyewall cycles could cause weakening, but it is highly likely that Frances will hit as a major hurricane. Where will Frances hit is the next question to answer. The global and regional models used by hurricane forecasters have tightly clustered on the central Florida coastline. The most likely place to experience the core of the storm is anywhere from West Palm Beach up to Vero Beach. But the storm could still hold surprises in the track department (remember Charley?), so a hurricane warning has been issued for the entire coastline from Florida City (south of Miami) to Flagler Beach (near Daytona Beach). Even if the forecast is dead on, a large section of the warning area will likely see hurricane force winds because of the size of the storm. Any significant deviation in the track could still bring the area of hurricane force winds further north or south, but that looks unlikely at this point. It is very important for everyone in the warning area to heed the directions of local emergency officials. People that live in low-lying areas or mobile homes should NOT stay in their homes. About 1.2 million people fit in this category and have been told to evacuate to safer locations. Also, remember that the high winds of a hurricane can extend well inland past the coast. Hurricane force winds can be felt as far inland as 150 miles or more in a strong, fast moving storm -- as Charley showed in the Orlando area. Frances is forecast to turn northwestward over Florida and weaken to tropical storm force about half a day after landfall. If it stays further west, it could cross Florida and restregthen in the Gulf of Mexico before a second landfall in the Florida Panhandle. Thus, residents as far west as Mobile, Alabama should keep an eye on this storm over the weekend. At 21Z, Frances was located about 375 miles east-southeast of the lower Florida East Coast, at 24.1N 74.8W, moving towards the northwest near 9 kt. Maximum sustained winds were at 120 kt and the minimum central pressure was 946 mb.
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