Last weekend provided perfect conditions for the formation of willy-willys, with hot days across much of the country. Gippsland, in Victoria, where this video was taken, experienced one of it's hottest days of the summer, with temperatures over 39°C in Bairnsdale, Sale, Warragul and Morwell. What's a willy-willy? Also known as a dust devil, a willy-willy is a vortex of air made visible by the dust particles and debris inside it. They form when a pocket of hot air rises quickly from the surface t