Australian Weather Calendar: April 2015

April photograph by Lucy Stevenson

Funnel cloud north of Cooma, New South Wales

When 25-year-old Lucy Stevenson spotted a long, twisting cloud from the Monaro Highway just north of Cooma (New South Wales) on Boxing Day 2013, she didn't know what it was. She snapped a picture on her iPhone, out of the window of her brother's moving car, and posted it on Twitter.

Lucy soon had her answer: It was a funnel cloud, created when water vapour in the air is condensed into droplets by rapidly rotating winds. Funnel clouds are usually associated with supercell thunderstorms. Some make contact with the ground, as this one did, and become tornadoes. Tornadoes are in fact not uncommon in Australia, but are rarely as strong as those in places more famous for them, such as parts of the United States.

Diagram