What is it?

A dust devil is a strong, well formed whirlwind. Most dust devils are harmless, but some can grow large enough to threaten people.

How is it formed?

Dust devils form when hot air near the surface rises quickly through a cold air pocket. The friction on which the dust devil travels produces a forward momentum while causing it to pick up more dust creating as stronger dust devil.

What is the intensity and duration?

Normally, most dust devils are very small and weak. Only lasting on minute after it is formed. Occasionally, it can be very large (300 feet in diameter) and have up to 60 m.p.h. winds. The longest period of time a dust devil has ever lasted is about 20 minutes.