Description

A steam devil is a small, weakly rotating column of condensed water vapour over water (or rarely over wet land) that has drawn fog into the vortex, thus rendering it visible. Typically, it is associated with steam fog (Arctic sea smoke), a type of fog that develops in very cold air above a relatively warm body of water or very wet land.

Smaller ones can form over ponds, hot springs, and geysers when the air is very cold. Larger ones can form over large lakes and oceans during cold air outbreaks while the water is still relatively warm, and can be an important mechanism in vertically transporting moisture.

Steam devils have only been reported and studied since the 1970s. They are weaker than waterspouts and distinct from them. They are more akin to dust devils in that they develop near the surface and have no “parent” cloud.