A dust devil is a small whirlwind, or air vortex, on land. Visible as a column of dust and debris. A dust devil forms when the air is clear and hot, which can set a situation, where one part of the ground, like dark asphalt of a parking lot, heats up faster than the ground around the asphalt. Dust from something like a baseball field may heat faster than the grass that is possibly around the baseball field. Which then, the moisture in the dirt combines in the air, and seems like it is chasing the warm air around in a circle. The warm and cold air them form a small, sort of tornado that picks up the dirt that is from said baseball field, and then making a dust devil.