(Corrects 5th paragraph characterization of Key West as the southernmost city in Florida, not in the United States)
By Michael Haskins
KEY WEST, Fla., Aug 18 (Reuters) - Store owners boarded up their windows but few Florida Keys residents fled as Tropical Storm Fay churned toward the United States on Monday after killing more than 50 people in the Caribbean.
It did not appear that the sixth storm of the 2008 Atlantic hurricane season would have time to reach hurricane strength, with top sustained winds near 74 miles per hour (119 km per hour), before passing the low-lying and flood-prone Keys.
But Fay was expected to become a hurricane before it strikes the west coast of Florida on Tuesday, somewhere near the beach resort area of Fort Myers, the Miami-based U.S. National Hurricane Center said.
Although its path was far from U.S. oil and gas rigs in the Gulf of Mexico, some energy companies pulled workers from offshore platforms. Orange juice futures prices shot up on fears Fay could hit the main citrus growing areas of central Florida.
In Key West, Florida's southernmost city where Ernest Hemingway wrote many of his novels, the mood was typically nonchalant. Few people there believed a strong storm or weak hurricane would pose a serious threat.
The popular Hog's Breath Saloon on Duval Street was one bar that closed down due to the poor weather forecast.
"We'll open tomorrow because we expect the weather will be nice," said general manager Charlie Bauer.
Many restaurants however remained open even as the wind began to pick up and a driving rain started to blow painfully through increasingly deserted streets.
"This isn't a hurricane. If the media wasn't down here hyping this up, this would be a non-event," grumbled Key West Island Books proprietor Marshall Smith.
The authorities in the archipelago had ordered visitors to evacuate on Sunday, creating bumper-to-bumper traffic on the highway out of the islands on the state's tip. By Monday the traffic had thinned considerably, police said.
The lost revenue would hurt the tourism-dependent Keys, said Karen Thurman, marketing manager for the Grand Key DoubleTree Resort on South Roosevelt Boulevard.
"But we must err on the side of caution," she said. "After seeing what happened in New Orleans, and that area, I think early evacuation of visitors is important for safety, especially in the Keys, where we only have one road out. Lives are more important than revenue."
New Orleans was swamped in August 2005 by Hurricane Katrina, which killed 1,500 people on the U.S. Gulf Coast and became the most expensive natural disaster in U.S. history.
By 2 p.m. EDT (1800 GMT) on Monday, Fay was located just 20 miles (30 km) southeast of Key West and its top sustained winds were at 60 mph (95 kph).
It was moving north-northwest at 14 mph (23 kph) and was expected to curve to the northeast into Florida's west coast. Densely populated Miami-Fort Lauderdale in the southeast of the state was buffeted by bands of heavy rains and gusty winds.
Fay crossed Cuba without apparently causing serious damage.
In Haiti, witnesses said about 50 people died when a bus tried to cross a river swollen by rain. Eight others were killed in Haiti and the Dominican Republic and two died in Jamaica when their car was caught in a flooded crossing.
The state of Florida deployed 500 National Guard troops, and schools in south Florida canceled class.
"This is not Charley," said Craig Fugate, Florida's director of emergency management, referring to a 2004 hurricane that reached Category 4 strength on the five-step Saffir-Simpson scale before slamming into Florida's west coast with devastating force. "This isn't the type of storm that's going to rip off a lot of roofs." (Additional reporting by Jeff Franks and Marc Frank in Havana, Michael Christie and Tom Brown in Miami, and Rene Pastor in New York; editing by Jim Loney and Mohammad Zargham)