Tropical Storm Isaac moved into the Caribbean Sea and may become a hurricane as early as today as it travels west on a path watched by commodity markets and those preparing for the Republican National Convention.
Isaac is forecast to strengthen and cross Haiti and Cuba before arriving at the southwestern Florida coast Aug. 27, the National Hurricane Center said. That’s the opening day of the Tampa session at which Republicans are expected to nominate Mitt Romney as their presidential candidate.
“At this point the error in our forecasts is so huge that it’s very difficult to tell what the risks would be” to land, said Jeff Masters, co-founder of Weather Underground in Ann Arbor, Michigan. “We’re not going to have an idea until Sunday at the earliest what kind of risk this poses to Tampa. It’s quite the drama.”
Orange-juice futures rose the most in more than seven weeks on ICE Futures U.S. in New York yesterday and natural gas gained on the New York Mercantile Exchange because of the storm.
“We’re paying extremely close attention to it,” Florida’s emergency management director, Bryan Koon, said in an interview. “We anticipate there will be impact to the state next week. But exactly where and how much remains to be seen.”
Isaac, the ninth named storm of the Atlantic hurricane season that runs through November, was 270 miles (434 kilometers) southeast of San Juan, Puerto Rico, the Miami-based center said in an advisory at 11 p.m. Atlantic time yesterday. The system, moving west at 20 miles per hour, packed maximum sustained winds of 45 mph. That’s below the minimum 74 mph speed of a Category 1 hurricane.
The storm may bring as much as 20 inches (50.8 centimeters) of rain and raise water levels by 5 feet (1.5 meters) above normal along the coast of Hispaniola, according to the advisory.
“Isaac could become a hurricane Thursday night or Friday,” the center said. “Some strengthening is forecast during the next 48 hours.”
Offshore oil and gas platforms and rigs may begin to shut in the next few days as the storm threat is better determined, said Jim Rouiller, senior energy meteorologist at Planalytics Inc. in Berwyn, Pennsylvania.
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. Florida is the second-largest orange grower, after Brazil.
Florida Governor Rick Scott urged residents to be prepared. Preliminary hearings scheduled to start today in Guantanamo Bay, Cuba, for Khalid Sheikh Mohammed, the alleged mastermind of the Sept. 11 terrorist attacks, were postponed by an Army judge because of the storm threat.
Alex Sosnowski, expert senior meteorologist for AccuWeather Inc. in State College, Pennsylvania, said that the storm is still several days away and may make landfall anywhere from eastern Florida to the Gulf Coast.
If it hits eastern Florida, weather in Tampa may be hot and dry. If Isaac moves into the Gulf, the city might have severe thunderstorms, gusty winds and drenching rain, he said.
“It’s going to be in the general vicinity of Florida in the first part of next week when the Republican National Convention is going on,” Sosnowski said. “Even without a direct hit, it could mean travel impacts.”
The path will depend on how strong Isaac gets while it is still in the Caribbean and how far north it goes, said Matt Rogers, president of Commodity Weather Group LLC, in Bethesda, Maryland. How the storm interacts with the larger islands of the Caribbean can also affect the track, as do weather patterns over the U.S.
“There are a lot of moving parts with this one,” Rogers said.
If the Tampa Bay area is expected to receive rain from the outskirts of the storm, the convention would probably proceed as normal, Koon said. If a direct impact looks probable, Koon said he’ll talk with convention officials about how to move delegates and reporters.
“Our concern from the state level is going to be the Floridians who live in the area,” Koon said. “Delegates who come down generally have the means to get back to where they need to go.”
Tampa is the second-largest metro area in Florida, after Miami, with nearly 2.8 million people, according to Census data. An estimated 50,000 are expected to attend the four-day convention, including 15,000 representatives of the media.
The Tampa Bay Times Forum, site of the gathering, is in a mandatory evacuation zone once storms reach 96 mph, a Category 2 on the five-step Saffir-Simpson scale, according to the Hillsborough County Hurricane Guide.
The most violent storm to hit the city, in 1848, sent 15 feet of water over land now home to the Tampa Bay Convention Center, where media will be headquartered, Masters said.
A tropical depression, the 10th of the hurricane season, formed yesterday about 1,045 miles west of the Cape Verde Islands, the hurricane center said.
The system is moving west-northwest with top winds of 35 mph on a track that may keep it east of the U.S., according to an advisory at 10:34 p.m. Eastern time yesterday. It’s expected to become a tropical storm today.