Isaac strengthens, draws closer to Florida  Isaac strengthens, draws closer to Florida  Isaac strengthens, draws closer to Florida  Isaac strengthens, draws closer to Florida  Isaac strengthens, draws closer to Florida  Isaac strengthens, draws closer to Florida  Isaac strengthens, draws closer to Florida  Isaac strengthens, draws closer to Florida  Isaac strengthens, draws closer to Florida  Isaac strengthens, draws closer to Florida  Isaac strengthens, draws closer to Florida  Isaac strengthens, draws closer to Florida  Isaac strengthens, draws closer to Florida  Isaac strengthens, draws closer to Florida  Miami (CNN) -- As Tropical Storm Isaac moved quickly through the Straits of Florida on Sunday, coastal communities in Florida issued mandatory evacuations and Republicans delayed the start of their national convention.  Residents along the Gulf Coast watched nervously as forecasters said the storm was moving west of its originally predicted path after passing through the Caribbean.  With sustained winds of 60 mph, Isaac lashed Cuba with strong winds and dumped rain on the island early Sunday. No major damage or injuries were immediately reported in Cuba. On Saturday, it slammed Haiti, where at least six deaths were reported.  Heavy rain was already falling in some parts of south Florida, where a tornado watch was in effect until 5 p.m. ET.  iReport: Rain pounds Palm Beach County  The outer bands of the storm extended as far as 205 miles from its center, which was roughly 50 miles southeast of Key West as of 1 p.m. ET.  Lee County, in southwest Florida, ordered residents in six communities, including the popular tourist spot of Fort Myers Beach, to evacuate, citing the possibility of significant storm surge.  The storm is expected to gain strength in the warm water of the Gulf of Mexico and become a hurricane by early Monday as it passes the Florida Keys.  By late Monday afternoon or early evening, Isaac's eye is expected to be west of Tampa, Florida. It is expected to make landfall again on Wednesday somewhere along the Mississippi coast. By Wednesday -- the seventh anniversary of Hurricane Katrina -- Isaac could be a Category 2 hurricane with winds of at least 96 mph. The hurricane center said areas of the Louisiana coast from Morgan City east are under a hurricane watch. The watch includes New Orleans.  "We are just on high alert. I know the anxiety level is high," New Orleans Mayor Mitch Landrieu said. "The storm is somewhat uncertain. Out of an abundance of caution we will begin to take these precautions as quickly as we can."  He said neither the airport, convention center nor Superdome would be shelters of last resort as they were in 2005.  "We are much, much better prepared structurally than before," he said, adding, "If you are called upon, you should leave."  Louisiana Gov. Bobby Jindal declared a state of emergency for the state and called for voluntary evacuations in 15 parishes.  Officials in Plaquemines Parish declared a state of emergency and began preparing for the storm by bolstering levees and adding additional flood protection devices to low-lying highway areas.  Florida Gov. Rick Scott said some areas in his state had no power.  "We are experiencing some minor outages in the southern part of the state," he said at a news conference in Tampa. He said his main concern for Tampa was no longer a direct hit from Isaac but strong winds from the storm's reach.  Even with the change in the storm's predicted track, GOP officials decided to push back Monday's scheduled start of the Republican National Convention in Tampa by one day, hoping the move will make it safer and easier for delegates to attend.  Some airlines had canceled some flights between airports in south Florida.  Jindal unsure about convention attendance - again  In Key West, the southernmost point in the United States and likely the first part of Florida to be hit by Isaac, storefront windows were boarded up, while hotels were largely vacant even though no evacuation orders had been issued.  Some in Key West, though, suggested they were ready and eager to ride out the storm.  "We came down here to have a good time, we're not going to let a hurricane get in the way," said Paul Cannella, who is visiting the Keys from Chicago. "I am a big believer in lifetime experiences, (and) I've heard about hurricane parties, so we're going to have some fun with it."  Bill Doktor, an iReporter from Punta Gorda, said he had put up hurricane shutters and already started a portable generator.  The rain comes in spurts, he said, pouring down for 15 minutes before subsiding for the rest of the hour.  Scientists from the U.S. Geological Society were concerned that Isaac, headed towards areas hit by Tropical Storm Debby in June, will compound damage done there, especially dune and beach erosion.  "Tropical Storm Debby eroded many beaches along Florida's west central coast, impacting the property of many gulf-side residents and hotels," Hilary Stockdon, a USGS oceanographer, said in a written statement. "Beaches typically take years to recover from severe storm impact."  A tropical storm warning was in effect for Florida's east coast from Sebastian Inlet southward to Ocean Reef, and along Florida's west coast and the panhandle from north of Bonita Beach to Indian Pass, including Tampa Bay.  "The likelihood of hurricane conditions occurring in southeast Florida is decreasing," the National Hurricane Center said.  "Tropical storm conditions are occurring in the tropical storm warning area along the Florida east coast. Tropical storm conditions are expected to spread northward along the west coast of Florida and into the eastern Florida panhandle in the tropical storm warning area tonight and Monday."  The U.S. Bureau of Safety and Environmental Enforcement said Sunday that 39 production platforms and eight oil rigs in the Gulf had been evacuated already. BP said it will evacuate all oil platform workers in the Gulf on Monday.  As preparations continued in Florida, authorities in Haiti were assessing Isaac's aftermath.  The storm left at least six people dead when it struck the impoverished Caribbean nation on Saturday, pounding camps where hundreds of thousands of people live in tents.  The country is still recovering from a devastating earthquake that struck more than two years ago, and its challenges are compounded by the fact it is led by a relatively new government with limited resources. All that said, the top U.N. humanitarian official in the nation praised the initial response efforts.  "So far, I think we're faring reasonably well in our response," Kevin Kennedy said Saturday, referring to the efforts of the Haitian government, U.N. agencies and nongovernmental organizations.  Focus turns to Florida as Isaac passes Haiti  Haitian radio reported that the worst damage was in the country's southeast where Isaac made landfall.  In the city of Jacmel, on Haiti's southern coast, the storm damaged houses and knocked out power. As many as 1,500 of the city's residents took refuge in a school serving as a shelter. Nationwide about 30,000 people were seeking new living accommodations, authorities said.  Jacmel Mayor Hugues Paul confirmed at least one death on the outskirts of his city, voicing concerns that more deaths will be reported.  An 8-year-old girl also died when a wall fell on her house in Thomazeau, near Port-au-Prince, the country's civil protection agency said.  At the Mega IV camp, where 8,000 Haitians live in makeshift shelters, fallen trees and flooding damaged hundreds of tents. Almost no one evacuated the camp before the storm, and authorities were searching the camp tent by tent for potential victims.  At another camp, Canaan, half the tents were blown away, according to an official statement on the radio.  Haiti's national electricity supplier at one point said that 30 out of the country's 32 electricity grids were down.  The storm also damaged the country's banana crop, the U.N. reported.  Share your photos, videos and stories from Isaac  iReport: Isaac floods roads and bridges on Santo Domingo  Photos: Tropical Storm Isaac takes aim at Florida  Photos: Finding beauty in violent storms  CNN's Martin Savidge, Gary Tuchman, Jim Spellman and journalist Jean Junior Osman contributed to this report.
Tropical Storm Isaac dumped rain and strong winds to Cuba early Sunday, picking up strength as it churned toward Florida.