How high can ‘dust devils’ extend?
I read a book that talks about dust devils more than 1,000 feet high. Is this possible?
Roy Kentish Crystal Lake
Yes it is. Dust devils form on sunny and, usually, hot days with light or calm winds. They form over fields or expanses of pavement or dirt. Air within several feet of the ground is heated strongly by sunlight and then rises into cooler air above it. This establishes an ongoing cycle, with hot surface air twisting and rising in a localized whirl that is usually about 50 feet in diameter but can be several hundred feet across. Wind speeds are usually 20 or 30 mph, but can surpass 50 mph. A typical dust devil is no more than a couple of hundred feet high and lasts a minute or two, but they can extend upward a few thousand feet and persist for a half-hour. In Phoenix dust, devils as high as 3,000 feet have been observed.