What the Americans call a hurricane is also referred to as a typhoon or a tropical cyclone, depending on where you live. Australians even have their own name: willy-willy. And while these powerful storms may be christened with different names – whether it is Emily, Mitch or Katrina – their births are very similar. Hurricanes are placed in five different categories – in the top level, winds of more than 250 kph are generated. The storms develop in tropical regions where the sea water is warm.Moist air rises quickly and vapours condense to form storm clouds. A continuing cycle of this evaporation and condensation, with converging equatorial winds at high altitudes, results in the hurricane’s out-of-control anti-clockwise rotation.
At the centre of the hurricane the wind speed is about 30 kph, but at the edges that can grow to up to 350 kph.A hurricane can be up to 900 kilometres long and 15 kilometres high, packing a punch that is 15 times more powerful than an atom bomb. Max Mayfield at the US Hurricane Centre said: “The greatest potential for large loss of life – and I want to be very clear about this – is from the storm surge, and that’s this rising water … possibly up to 25 feet, to the east of where the centre crosses the coastline.”
History has shown how catastrophic hurricanes can be. One of the US’s worst was Camille, in 1969, a disaster that left about 250 people dead. Just last year Hurricane Ivan left 38 people dead. Among the most deadliest hurricanes ever recorded was Mitch, claiming the lives of at least 10,000 people in Honduras and Nicaragua in 1998.