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.