Australian Weather Calendar - April 2014

April photograph by Cheryl Billett

Spectacular nature courtesy of the jet age

Cheryl Billett of Echunga in the Adelaide Hills was in the kitchen one evening when her husband Graham called from outside, 'Grab your camera and have a look at this.' She dashed outside to see clouds and rain coloured dark orange by the sunset, along with white vapour trails. 'I'd never seen anything like it before, even though we do get some nice sunsets up here. It was a once-in-a-lifetime fluke shot.'

Vapour trail are thin clouds that form when air heated by aircraft engines cools quickly and water vapour condenses. The colder and more humid the atmosphere, the longer a vapour trail will generally last, sometimes for hours.

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