The live updates on this event have now concluded, but 1 NEWS NOW will continue to bring you news as it happens.
9.25am: Two more storms in the Gulf of Mexico and the Atlantic have joined Hurricane Irma as official hurricanes, the NOAA National Hurricane Centre reports. Hurricanes Katia and Jose were both upgraded this morning, New Zealand time. They are both currently Category 1, while Irma remains a Category 5. Jose remains far east of Irma, out in the Atlantic, while Katia is centred off the eastern coast of Mexico in the Gulf.
9.08am: Heavy rain and strong winds have begun to hit the island nation of Puerto Rico on the northeastern coast as Hurricane Irma approaches. The Associated Press reports that France has sent emergency supplies to the islands of Saint Martin and Saint Barthelemy, where Irma has reportedly kripped off roofs and cut all electricity.
9.05am: Reports indicate that Saint Martin's well-known airport has been severely damaged by Hurricane Irma. The airport is often seen in videos where tourists at a beach nearby cling to a fence as planes come in to land just metres above their heads.
8.48am: Two nuclear power plants lie in the potential path of Hurricane Irma, and the state of Florida is considering whether they should be shut down. The Miami Herald reports the Turkey Point and St. Lucie plants are being prepared for the storm and staff are being briefed and readied. However, neither of the plants have yet made a call on whether their reactors will be shut down. A spokesman told the Herald that while shutting down a reactor takes a lot of time, it would be done well in advance of the storm making landfall, if it were confirmed. "If we anticipate there will be direct impacts on either facility we’ll shut down the units," Florida Power & Light spokesperson Peter Robbins said.
8.40am: Florida Governor Rick Scott has given a serious warning to residents, urging them to "get out now" as the state urgently brings in petrol to fuel the vehicles of evacuees. Mr Scott told the Associated Press that the storm is a very serious situation for Florida and urged residents not to "sit and wait for this storm to come". Tourists in the state are already under a mandatory evacuation order, which began yesterday, NZT.
8.25am: Al Jazeera reports the French overseas territories minister Annick Girardin has said two people have died from Hurricane Irma in the French Carribbean territories. Two others are also seriously injured.
8.20am: The French Government says contact has been lost with the island territory of Saint Martin as Hurricane Irma ravages the small Caribbean island.
AFP reports many of the government's "most solid" government buildings have been destroyed by sustained 295km/h winds there.
The island is home to about 80,000 people, and videos show incredibly strong winds and considerable flooding.
Irma - the most powerful storm ever recorded from the Atlantic, is forecast to continue towards the northwest and could possibly impact Florida later in the week.
The eye of the storm is currently heading for the island of Anguilla.
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