Hurricane Irene strengthened to a category 3 tropical cyclone – with winds of 115mph – over the Bahamas on Wednesday as it moved north towards US, where is expected to sweep past the Carolinas and upwards at the weekend.
Irene is the first hurricane to threaten the US this year and is expected to intensify further over the coming days. The US National Hurricane Centre (NHC) warned of an “extremely dangerous” storm surge.
Forecasters predict that Irene will hit North Carolina’s Outer Banks region on Saturday afternoon and then track up the eastern coastline through to the New England.
Even if the centre of the storm stays offshore, the hurricane could hit cities including Washington and New York with winds and rain, and cause coastal flooding and power cuts.
“Irene will be a large storm, impacting areas far from the storm centre track,” Jeff Masters, a hurricane expert at forecasters Weather Underground, wrote in his blog.
But as forecasts of more than four days can have a margin of error of up to 200 miles, US emergency officials have warned the US east coast to be on the alert for what they describe as a large and potentially dangerous storm.
Residents along the coast were already jittery after a 5.8 magnitude earthquake was felt in Washington and cities from the Carolinas to Canada on Tuesday.
At 8am local time, Irene was carrying winds of 115 and was about 55 miles south-east of Acklins Island in the Bahamas, the Miami-based NHC said.
The wind speed made it a category 3 hurricane on the five-step Saffir-Simpson intensity scale, posing a high risk of injury and death from flying and falling debris.
Forecasters see Irene swinging north from Thursday, sparing Florida and Georgia from any direct impact and heading towards to Cape Hatteras, North Carolina, where the Outer Banks barrier islands are often battered by storms.
If Irene makes a direct landfall, it will be the first hurricane to hit the US since Ike pounded the Texas coast in 2008. But forecasts showed it posing no threat to US oil and gas installations in the Gulf of Mexico.
AccuWeather said Irene would strike the Outer Banks on Saturday afternoon or evening, but the hurricane would affect the eastern Carolinas much sooner.
North Carolina’s governor, Bev Perdue, urged residents to ensure they had three days worth of food, water and supplies.
Voluntary evacuations were to begin on Wednesday for parts of the Outer Banks, whose beaches are popular summer holiday spots.
Irene drenched the north-eastern Caribbean islands earlier in the week. The first death from the storm was reported on Tuesday in Puerto Rico, where a woman was swept away. Heavy rains have continued there, causing flooding and mudslides. Nearly 300,000 residents were without electricity and 58,000 were without water.
