Tropical Storm Isaac is expected to cross the Leeward Islands today and enter the Caribbean Sea, where it may become a hurricane tomorrow, according to the U.S. National Hurricane Center.
Isaac, the ninth named storm of the Atlantic hurricane season, was about 210 miles (338 kilometers) east of Guadeloupe and moving west at 19 miles per hour, the Miami-based center said in an advisory at 8 a.m. local time. The system’s maximum sustained winds were 45 mph, below the minimum 74 mph speed of a Category 1 hurricane.
The center’s tracking map shows the system crossing Haiti as a hurricane on Aug. 25 and striking Cuba the next day before arriving at the edge of Florida Keys early Aug. 27. A hurricane churning over Florida next week would coincide with the Republican National Convention, at which the party will officially nominate Mitt Romney as its candidate for president. The event is scheduled for Aug. 27 to Aug. 30 in Tampa, Florida.
“The waters Isaac will be moving across represent high- octane fuel for additional strengthening,” said Jim Rouiller, senior energy meteorologist at Planalytics Inc. in Berwyn, Pennsylvania. “This along with very favorable upper-level winds makes this storm a serious threat to U.S. interests across the eastern half of the Gulf along with Florida and eventually the southeastern U.S.”
Offshore oil and gas platforms and rigs may begin to shut down in the next few days as the threat from Isaac is better determined, Rouiller said in an e-mail interview. The Gulf of Mexico is home to 29 percent of oil production, 6.3 percent of U.S. natural-gas output and 40 percent of refining capacity, according to the U.S. Energy Department.
Computer forecast models “are really having trouble” getting an exact fix on where Isaac may go, said Matt Rogers, president of Commodity Weather Group LLC, in Bethesda, Maryland.
Early today, one model forecast the storm may arrive off the western Florida coast near Tampa as a strong hurricane, he said by telephone. Many European models suggest Isaac may move west in the Gulf of Mexico and go ashore near New Orleans.
“Unfortunately, there is a huge spread among the models and that is going to keep confidence low,” Rogers said. “I hope we get this resolved by Friday.”
Rogers said the path will depend on how strong Isaac gets while it is still in the Caribbean and how far north it goes. How the storm interacts with the larger islands of the Caribbean can also affect the path, as do weather patterns over the U.S.
“There are a lot of moving parts with this one,” Roger said.
Hurricane watches, which mean storm conditions may strike in 48 hours, were issued for Puerto Rico, Vieques, Culebra, the U.S. Virgin Islands, the British Virgin Islands and the south coast of the Dominican Republic, the center said. Tropical-storm warnings were in effect for islands including Martinique, Dominica, Guadeloupe, St. Martin and St. Kitts.
As much as 8 inches (20.3 centimeters) of rain may fall over the northern Windward Islands and the Leeward Islands, according to the hurricane center. A storm surge may raise water levels as much as 3 feet (0.9 meters) above normal in the Northern Leeward Islands, Puerto Rico, and the U.S. and British Virgin Islands, “accompanied by dangerous waves,” it said.
The center was tracking two other weather systems in the Atlantic. A low-pressure area 725 miles west-southwest of the Cape Verde Islands has a 90 percent of becoming a tropical cyclone in the next two days, it said. Another over the far- western Gulf of Mexico has a near zero percent probability of turning tropical.
© Copyright 2013 Bloomberg News. All rights reserved.