* Storm now forecast to become hurricane on Friday
* Tampa mayor plays down threat to Republican convention
MIAMI Aug 22 Tropical Storm Isaac swirled over
the Caribbean on Wednesday and was forecast to become a
hurricane as it moved on a track that would put it off the coast
of Florida on Monday, the opening day of the Republican National
Convention in Tampa.
The threat to the Caribbean was certain, with Isaac already
closing in on the Leeward Islands and hurricane watches in
effect for many places, including Puerto Rico and the U.S. and
British Virgin Islands.
Isaac could also potentially threaten U.S. energy interests
in the Gulf of Mexico, weather experts said. It was centered
about 210 miles (340 km) east of Guadeloupe early on Wednesday,
the U.S. National Hurricane Center (NHC) said.
Isaac had top sustained winds of 45 miles (75 km) per hour
and was forecast to become a hurricane by Friday, as it neared
the coast of Hispaniola, the island shared by the Dominican
Republic and flood-prone Haiti. Computer forecast models showed
the storm moving west-northwest across the island on Friday.
There was still a lot of uncertainty about the storm's path
after its projected passage over Cuba on Saturday and Sunday.
But computer models showed it making landfall in South Florida
or brushing either side of the Florida Peninsula by late Sunday
or early Monday.
It is far too soon to say whether Isaac might take direct
aim at Tampa, on Florida's Gulf Coast, where the Republican
convention is set to run from Monday through Thursday.
But Lixion Avila, a senior hurricane specialist at the
Miami-based NHC, suggested it would be foolish for anyone to
think Tampa, where Republicans will nominate Mitt Romney as
their presidential candidate, was out of harm's way.
"With the convention or without the convention, I can tell
you this is Aug. 22, hurricane season, and normally anywhere in
Florida or the Gulf of Mexico we should monitor any system that
forms," he said.
Tampa Mayor Bob Buckhorn, a Democrat, said he wasn't really
worried about Isaac, however.
"We're watching it. We're tracking it. I think we're going
to be OK but we'll be prepared in the event it heads this way,"
Buckhorn told CNN.
"We hope it moves further away from us, but if it doesn't
it's still going to be a great convention and I think the
Republican National Committee is going to be happy," he said.
OJ PRICE JUMP
Florida has not been hit by a major hurricane since 2005 and
no one is forecasting that Isaac will strengthen into anything
more than a weak Category 1, with top sustained wind speeds of
about 80 miles (129 km) an hour.
Still, the threat to Florida triggered a jump in New York
orange juice prices on Wednesday, as they surged to a six-week
high in early trading.
Florida produces more than 75 percent of the U.S. orange
crop and accounts for about 40 percent of the world's orange
juice supply, making it key to volatility in orange juice
The Atlantic hurricane season runs from June 1 through Nov.
30 and August has traditionally been an active month in the
six-month period. Friday is the 20th anniversary of Hurricane
Andrew, which caused widespread damage when it came barreling
ashore south of Miami on Aug. 24, 1992.
Lurking behind Isaac, the NHC said another tropical
depression formed over the eastern tropical Atlantic on
Wednesday, about 860 miles (1.385 km) west-southwest of the Cape
Verde Islands. It was packing winds of 35 mph (55 kph) and will
take the name Joyce if it becomes a tropical storm.