Fig1 Thunderstorm Development
2.3.1.1 Thunderstorm Stages The life cycle of a thunderstorm includes three stages: cumulus, mature, and dissipating. Cumulus Stage — is the beginning of all thunderstorms. The size of the updraft region (cell) becomes larger and the cloud grows in an unsteady succession of upward bulges, as evident by the thermals that reach to the top. Strong vertical winds, severe turbulence, icing and lightning, are typical hazards that an aircraft could encounter at this stage. Mature Stage — is reached when the precipitation-induced downdraft reaches the ground. Heavy rain or hail, and in colder areas sleet or snow, are driven by strong downdrafts. Wind shear, lightning and thunder develop because of friction between the opposing air currents. At this stage, the hazards can be devastating for any aircraft. Dissipating Stage — is reached when the updraft is overwhelmed by the precipitation induced downdraft. With no source of moisture, the associated hazards decrease and the entire thunderstorm gradually dissipates.
2.3.1.2 Thunderstorm Types There are several types of thunderstorms: The air mass thunderstorm, the severe thunderstorm, and squall-line thunderstorm. An air mass thunderstorm consists of one cell
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