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During the day, the sun heats the earth’s surface. The soil and trees become warmer than the air in contact with them and in turn heat the air. At night, the colder air settles to the ground and the warmer air rises forming an inversion.

Radiant frost occurs when a sudden drop in temperature due to irradiation of the trees and soil causes the surrounding air to cool rapidly. The chilled air settles into the lowest areas in the orchard or growing field causing frost damage.

Wind machines pull the warm air from the inversion layer down into the crop zone, raising temperatures as much as six degrees, thus saving crops from being injured.