Hurricane Irma has begun its assault on Florida with the storm’s northern eyewall reaching the lower Florida Keys as a powerful Category 4 storm.
Irma lashed the area with maximum sustained winds near 215km/h and the US National Hurricane Centre said it was expected to remain a powerful storm as it moved through the Florida Keys and near the state’s west coast.
As of 2100 AEST on Sunday, the hurricane was centred about 25km south-southeast of Key West, Florida, and was moving northwest at 13km/h.
The National Weather Service issued tornado warnings for a wide swath of Monroe, Miami-Dade and Broward counties in South Florida. There were no immediate reports of tornadoes touching down.
Tens of thousands in Florida are huddled in shelters as the hurricane threatens to make a catastrophic hit on the state. Around 6.3 million people – about 30 per cent of the state’s population – have been been told to evacuate.
In the Tampa Bay area, access to all of Pinellas County’s barrier islands, including the popular spring break destination of Clearwater Beach, was shut off.
The leading edge of the immense storm bent palm trees and spit rain across South Florida, knocking out power to hundreds of thousands of homes and businesses, as the eye approached Key West.
More than 500,000 homes in Florida have lost power, energy company FPL reports on its website. Irma could eventually leave millions of homes in the state without electricity, experts said.
Florida Governor Rick Scott had warned residents in the state’s evacuation zones on Saturday that “this is your last chance to make a good decision.”
But because the storm is up to 640km wide, the entire Florida peninsula was exposed. Forecasters said the greater Miami area of six million people could still get life-threatening hurricane winds and storm surge of 4m.
Irma was at one time the most powerful hurricane ever recorded in the open Atlantic with a peak wind speed of 300km/h last week. It left more than 20 people dead across the Caribbean and as it moved north over the Gulf of Mexico’s bathtub-warm water of nearly 90 degrees, it was expected to regain strength.
Meteorologists predicted Irma would plough into the Tampa Bay area Monday morning. The area has not been struck by a major hurricane since 1921, when its population was about 10,000, National Hurricane Centre spokesman Dennis Feltgen said. Now around three million people live there.