Track forecast for Ike
Ike has begun a west-southwest motion in recent hours, which increases the probability that the hurricane will enter the Southeast Bahama Islands on Sunday. The computer models which called for this more southerly path include the GFDL and HWRF models. With its latest run (06Z, 2am EDT) the GFDL takes Ike through the Southeast Bahamas and Turks and Caicos Islands as a Category 3 hurricane early Sunday morning. The HWRF has the same track, but makes Ike a Category 4. The two models then diverge, with the GFDL taking Ike into eastern Cuba as a Category 3 hurricane on Monday, and along the length of Cuba into the Florida Keys as a Category 2 hurricane on Wednesday morning. The HWRF has Ike skirting the northern coast of Cuba, arriving at Key Largo, Florida as a Category 4 hurricane on Tuesday night.
Considerable uncertainty surrounds the path of Ike once the storm reaches the vicinity of South Florida, since a trough of low pressure capable of turning Ike to the north will be passing to the north. A turn to the north over South Florida, or just on either side of the state is possible. One possible track, similar to the NOGAPS model forecast, takes Ike near or over Miami, then northwards towards North Carolina. This is a track similar to Hurricane Floyd of 1999. Another feasible track, similar to the HWRF solution, is like Hurricane Donna of 1960, which blasted through the Keys as a Category 4 hurricane, then up the west coast of Florida.
It is also possible that the trough of low pressure will not be strong enough to turn Ike to the north, and that the storm will enter the Gulf of Mexico. A second trough of low pressure would then turn Ike north, resulting in a n eventual landfall on the Gulf Coast between the Florida Panhandle and Texas. This is the forecast of the ECMWF and GFS models. My current thinking is along these lines:
20% chance Ike will hit the east coast of Florida.
30% chance Ike will hit the Florida Keys.
30% chance Ike will hit Cuba. If this happens, there is 30% chance it would miss Florida and head into the Gulf of Mexico.
10% chance that Ike will miss Florida, but hit further north along the U.S. coast.
10% chance Ike will curve north out to sea and not hit the U.S.
Overall, I'd give the Gulf Coast a 70% chance of getting hit (including the west coast of Florida).
Florida Keys are at high risk
The Florida Keys are highly vulnerable to hurricanes, and are at great risk from Ike. With only one road connecting the Keys to the mainland, a 48-72 hours are required to evacuate the Keys. Tropical storm force winds can be expected in the Keys on Tuesday afternoon, which means officials in the Keys may need to start ordering evacuations on Saturday. This would likely begin as an evacuation of visitors and tourists on Saturday afternoon or Sunday morning.