How It Works

Video: Incredible waterspout tornadoes form over Australia

Near the coastal suburb of Terrigal on the New South Wales coast, Australia’s Channel 7 filmed this amazing footage of swirling air columns moving along the surface of the water, forming waterspout tornados. Heavy rain and strong winds led to the formation of the 600m (2000 feet) high plumes of water.

Waterspouts normally form in dry and humid air that is contrasted by cooler air in a cloud, often one as tame as a cumulus cloud. The cold air rotates around the warm air, in turn creating water vapour. This water vapour is pulled upwards into the swirling column of cool and warm air to form the visible waterspout. They normally form in groups and, while mostly harmless – with an average top speed of 50mph (81kph) – some waterspouts have been known to reach 200 mph (322 mph) and even overturn boats.