Aug. 21 (Bloomberg) -- Tropical Storm Isaac, the ninth named storm of the Atlantic hurricane season, was heading toward the Lesser Antilles and is forecast to emerge over the eastern Caribbean Sea within two days.
Isaac, about 435 miles (700 kilometers) east of Guadeloupe, is moving west at 17 miles per hour, the Miami-based National Hurricane Center said in an advisory before 8 p.m. New York time. The storm, with maximum sustained winds of 40 mph, formed earlier today about 500 miles east of Guadeloupe.
The system is forecast to move through the Leeward Islands tomorrow evening and emerge over the eastern Caribbean Sea the next morning, the hurricane center said. It is predicted to strengthen over the next 48 hours. Tropical storm warnings have been issued for islands including Dominica, Guadeloupe, St. Kitts, Nevis, Antigua and Barbuda.
Tropical storm conditions are expected to reach warning areas by tomorrow afternoon, “making outside preparations difficult or dangerous,” the center said.
A system becomes a tropical storm when sustained winds reach 39 mph and a hurricane when they reach 74 mph.
The center’s tracking map shows the system crossing Haiti as a hurricane on Aug. 25 and striking Cuba the next day.
Two computer models are suggesting a Florida landfall that may affect the Republican National Convention, Jeff Masters, co-founder of Weather Underground in Ann Arbor, Michigan, said on his blog. The convention, at which the party will officially nominate Mitt Romney as its candidate for president, is Aug. 27 to Aug. 30 in Tampa, Florida.
“It would take a ‘perfect storm’ sort of conditions to all fall in place” for the system to reach Tampa as a hurricane during the convention, Masters said. “But that is one of the possibilities.”
Storm watches were posted for Puerto Rico and the U.S. Virgin Islands, among others. A warning means storm conditions are expected within 36 hours. A watch means tropical storm impact is possible within 48 hours.
As much as eight inches (20 centimeters) of rain may fall over the Leeward Islands and the northern Windward Islands, the center said. A storm surge may raise water levels as much as 3 feet (0.9 meters) above normal tide levels in the northern Leeward Islands, “accompanied by dangerous waves” near the coast.
The center is tracking two other Atlantic systems. A low-pressure area over the far western Gulf of Mexico has a 20 percent chance of becoming a tropical system in the next two days. Another, 550 miles southwest of the Cape Verde Islands, has a 60 percent probability of becoming tropical.
To contact the reporter on this story: Charlotte Porter in New York at Cporter11@bloomberg.net.
To contact the editor responsible for this story: Dan Stets at email@example.com