The tropical storm watch for the Florida Keys is being dropped.
Isidore is now centered about 100 miles southwest of Havana, or about 65 miles east of the western tip of Cuba. Movement is still to the west-northwest at about eight miles an hour, with top sustained winds of about 105 miles an hour.
The passage over Cuba is expected to stop Isidore from strengthening. But the increase in power will resume once it's back out over open water Friday evening and Saturday.
There's still a lot of uncertainty about what Isidore is going to do once it's in the Gulf. Chances of U.S. landfall are considered about even anywhere from Brownsville around to the Tampa Bay area.
Forecasters believe Isidore might wander erratically over open water for a while, gaining power without taking definite direction. But they also say the guidance seems to be shifting westward, which would be good news for the Florida peninsula.
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