A microburst is a wind pattern that descends from rain clouds during spring and summer months. When this stream of falling air, or down flow, hits the ground, the wind fans out horizontally into an outflow. In this way it resembles the spray pattern that water from a kitchen faucet makes when it hits the bottom of the sink. By producing a strong divergence of wind, the microburst outflow causes a condition known as wind shear, a quick change in the wind's speed or direction. There are basically two types wet and dry. The main distinguishing characteristic between the two is the prevailing environment in which they are produced Dry microbursts, as the name implies, develop in an extremely dry environment where moist convection is just barely possible. They often occur from the front range of the Rocky Mountains to the Western Plateau region. The atmosphere is moist at high altitudes, but at lower altitudes conditions are exceedingly dry. The process of a microburst begins when the updrafts in a convective-type cloud can no longer support the weight of the ice and water particles. As the particles begin to fall, they drag the air downward, causing a downdraft.( Golden, J. H., and M. E. Sabones, 1991) This is the beginning of a precipitation-induced downdraft. The downward motions are strengthened when air from outside the cloud is mixed with saturated air of the cloud. As the moist air descends through the cloud and eventually below the cloud deck, evaporation of the water particles further cools the air and increases the downward motion. In addition, snow melts at lower elevations, contributing to the cooling of the air and the strength of the downdraft.
