Steam Devil - Occurrences

Occurrences

Steam devils are seen on the Great Lakes in early winter. They occur in the Atlantic off the coast of the Carolinas when cold air from the continent blows across the Gulf Stream. Steam devils can occur on small lakes and even over hot springs, but rather more rarely than on large bodies of water. It is also possible for steam devils to form over wet land if the air is cold and the sun is heating the ground.

Small steam devils occur at some of the larger hot springs in Yellowstone Park where a layer of steam fog hangs over the pools and wind can start to lift it up into fog streamers. One such example is the Grand Prismatic Spring in the Yellowstone Midway Geyser Basin. The air temperature can be high in terms of human comfort when the steam devils form. In 1982 a cluster of seventeen steam devils was observed when the air temperature was between 17 and 21°C. Although this is much higher than, for instance, the temperature of the air over the Great Lakes, the water temperature is also proportionately higher, being very close to boiling, so the temperature difference is still 79°C.

Another well known location in Yellowstone, the Old Faithful geyser, produces horizontal steam devils. In all, Yellowstone probably has the most frequent occurrences of accessible steam devils anywhere, with several steam devils being produced every hour at the most productive locations. Steam devils over geyser basins were first reported by Holle in 1977.