Authorities in Florida have begun bracing for the potential arrival of Hurricane Irma, a roiling storm that intensified into "an extremely dangerous Category 5 hurricane" as it churned toward the United States.
Even as millions across Texas reel from the impact of Hurricane Harvey, which battered the region with record-setting rain and was blamed for at least 60 deaths, Irma gathered strength in the Atlantic, prompting increasingly dire forecasts as well as hurried storm preparations in Florida, where a major hurricane has not made landfall since 2005.
Officials have begun urging people in Florida to leave areas that could take a direct hit from Irma. Miami-Dade County Mayor Carlos A. Gimenez said officials could ask some of the county's 2.7 million residents to begin evacuating as early as Wednesday (local time), calling Irma's potential impact an "all hands on deck" situation for local officials.
"This hurricane is far too powerful, poses far too great a threat for us to delay actions any further," Gimenez said at a news briefing.
Gimenez said county residents with special needs will be evacuated on Wednesday morning, and more evacuations may be ordered in Miami-Dade, the state's most populous county.
He also urged people in the county to have at least three days of food, water and other basic supplies on hand.
"This is a powerful storm which poses a serious threat to our area," Gimenez said. He added: "I would rather inconvenience our residents on this occasion than suffer any unnecessary loss of life if in fact we are hit by Hurricane Irma. It is still too early to know if we will take a direct hit."
Officials in Monroe County, home of the Florida Keys, a popular tourist destination, said they had issued a mandatory evacuation for tourists beginning on Wednesday morning at 7am. A mandatory evacuation for residents was also issued for Wednesday at 7pm.
The county has about 80,000 residents and regularly draws throngs of visitors who travel to the Keys, a series of islands off South Florida and connected to the rest of the state by US Route 1.
Monroe County officials said they urged residents and tourists to begin planning to evacuate immediately, saying that "the earlier people leave the Keys the less traffic they are likely to encounter". Authorities also said Monroe County schools would close Wednesday and remain shuttered until further notice, and hospitals had begun planning to evacuate patients.
"We're pros at this," Monroe County administrator Roman Gastesi said. "Obviously this is a big one, and this could be the big one. But folks out here are really connected to the weather and so we know what to do."
Florida Governor Rick Scott who has declared a state-wide emergency, wrote to President Donald Trump on Tuesday asking him to declare a pre-landfall emergency in Florida, warning that Irma may require large-scale evacuations. He also asked for federal assistance in constructing emergency berms to protect areas across the state already battered last year by flooding caused by Hurricane Matthew, which raked the state with punishing rain and winds before making landfall in South Carolina.
The last major hurricane - registering as a Category 3 storm or stronger - to make landfall in Florida was Hurricane Wilma in October 2005. Wilma was also the last major hurricane to make landfall in the United States until Harvey arrived in Texas late last month.
The National Hurricane Centre said on Tuesday morning that Irma had become a Category 5 storm. National Oceanic and Atmospheric Administration Hurricane Hunters reported maximum wind speeds of 282km/h - making it among the strongest hurricanes recorded in the Atlantic Ocean, according to the Post's Capital Weather Gang.
The hurricane centre said Irma's intensity may fluctuate, but it is expected to remain a Category 4 or 5 storm over the coming days. The center was blunt about Irma's potential impact, calling the storm "extremely dangerous" and "potentially catastrophic".
The Capital Weather Gang said Irma's forecast track shifted to the south and west over the weekend, putting it on course to approach the Florida Keys by Saturday.
Although the storm's exact path is unclear, the Capital Weather Gang's meteorologists issued similarly unnerving warnings of Irma being "likely to make landfall somewhere in Florida over the weekend" and saying that "the impact could be catastrophic".
The hurricane's surging growth has sent many Floridians into familiar pre-storm routines of preparing hurricane shutters, stocking up on supplies and nervously monitoring the news.
"Everyone should continue to monitor, check supplies, and be ready to implement action plans," the National Weather Service in Miami posted Tuesday morning on Twitter.
Scott has activated 100 members of the Florida National Guard and said he had directed all 7,000 members to report for duty on Friday. On Monday, Scott signed an executive order declaring an emergency in each of Florida's 67 counties, pointing to forecasts at the time warning that Irma could make landfall in the southern or southwestern parts of the state and "travel up the entire spine of Florida."
"Hurricane Irma is a major and life-threatening storm and Florida must be prepared," Scott said in a statement accompanying the order.
Governor Scott said Irma's potential impact on millions of people in Florida and beyond warranted the emergency declaration, which ordered state officials to waive tolls on public highways and prepare public facilities such as schools to be used as shelters.
"In Florida, we always prepare for the worst and hope for the best and while the exact path of Irma is not absolutely known at this time, we cannot afford to not be prepared," Scott said. "This state of emergency allows our emergency management officials to act swiftly in the best interest of Floridians without the burden of bureaucracy or red tape."
The University of Miami said Tuesday it was cancelling classes beginning on Wednesday and through the end of the week at two of its campuses, including its main property in Coral Gables, south of downtown Miami.
The warnings in Florida arrive not long after the state marked the 25th anniversary of Hurricane Andrew's devastating landfall there, and as residents - like many others nationwide - have spent recent days glued to news reports documenting Harvey's mammoth impact in Texas.
If Irma does make landfall as a Category 4 storm or stronger so close after Harvey's impact on the Gulf Coast, it will be the first time on record that two storms of that strength hit the United States during the same hurricane season.
Other areas also looked warily at Irma as it travelled through the Atlantic. The National Hurricane Centre said Tuesday there could be up to 30cm of rain across parts of the Virgin Islands and Puerto Rico.
"Hurricane conditions are expected to begin within the hurricane warning area in the British and US Virgin Islands and Puerto Rico on Wednesday, with tropical storm conditions beginning tonight," the Hurricane Centre said. "Hurricane and tropical storm conditions are possible within the watch area in the Dominican Republic by early Thursday."
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