Cruise Irma to strike the heart of the cruise industry By Tom Stieghorst / September 08, 2017 Share 1 Miami is the busiest cruise port in South Florida and the world. -- Forecasters at the National Hurricane Center have narrowed Hurricane Irma's path sufficiently that it is all but certain to strike South Florida and the heart of the worldwide cruise business as a historically powerful storm. Irma is much larger than Hurricane Andrew, which had winds above 156 miles an hour and devastated the southern end of Miami-Dade County 25 years ago.The current consensus forecast has the storm driving through the upper Florida Keys and into Miami on Saturday night or Sunday morning. Sustained winds are expected in the range of 130 to 156 mph.In contrast, Superstorm Sandy had 70 mph winds when it made landfall near Brigantine, New Jersey, in 2012. As a Category 4 on the Saffir-Simpson scale, Irma can be expected to produce wall failures, with the complete structural failure of some small residences, according to the hurricane center."Heavy, irreparable damage and near-complete destruction of gas station canopies and other wide-span overhang type structures are common," a hurricane center primer says. "Mobile and manufactured homes are often flattened. Most trees, except for the heartiest, are uprooted or snapped, isolating many areas. "These storms cause extensive beach erosion, while terrain may be flooded far inland. Total and long-lived electrical and water losses are to be expected, possibly for many weeks."Many cruise lines maintain their headquarters in South Florida, including the three biggest: Carnival Corp., Royal Caribbean Cruises Ltd. and Norwegian Cruise Line Holdings. The three busiest cruise ports in the world -- PortMiami, Port Everglades and Port Canaveral -- are all on the east coast of Florida.All of the cruise lines have made extensive preparations, including canceling cruises this weekend that originate in Florida. Ships went out to sea on Thursday away from the storm. Royal Caribbean is using the Enchantment of the Seas as a floating hotel for employees and their families. Norwegian Cruise Line said passengers from two shortened cruises who did not secure flights out of Florida are on the Norwegian Escape, which is carrying its full capacity of about 4,000 passengers away from the storm. The Carnival Paradise left Tampa as scheduled on Thursday, bound for Havana, as did the Carnival Sensation from Miami, bound for Cozumel. Carnival has canceled five cruises through Sept. 10.Cruise ports and airports remained open as of mid-morning on Friday, but are expected to close Friday night or Saturday as winds reach 55 miles an hour."Irma is likely to make landfall in southern Florida as a dangerous major hurricane, and bring life-threatening storm surge and wind impacts to much of the state," according to the hurricane center's latest advisory.Irma is expected to have passed through the state by Monday morning.