There are three main conditions to consider in order to have a thunderstorm. These are adequate moisture, an unstable mass, and the lifting force of heat. Let's look first at the initial developing stage of a thunderstorm. The first step is to have an uplifting of moist airmasses into the higher levels of the atmosphere. These masses require input from the sun onto the ground. The ground radiates heat that is lifted up to higher elevations and toward a mass of cooler air. Cumulus clouds are in this first stage, showing up because of condensation of water vapor. Remember that condensation gives off heat by itself so that the air is lifted further through convective processes. When the warmed air leaves the lower aspect of the clouds, low air pressure is left behind. Huge amounts of moisture enter the atmosphere. After this, the thunderstorm is considered mature. Anvil clouds can be seen and warm air rises until it reaches the tropopause. Cumulus clouds become cumulonimbus clouds and air is forced to spread below the tropopause out from the center. The raindrops get much heavier and often freeze into ice particles. These will fall and melt to become rain. Prolonged updrafts will lead to ice so large that hail results. The coexistence of updrafts and rain-drenched downdrafts mean the thunderstorm is mature. Inside the clouds is turbulence and the chance for wind, lightning, and tornadoes. The storm may simply rain out as long as there is little wind shear. The dissipation starts when the downdrafts exceed the updrafts. This can happen quickly unless there is a supercell. The downdraft will push through the clouds and often hit the ground. With nowhere to go, the air spreads out. You will call this a downburst. Such a strong cold downburst blocks any updraft from occurring. The thunderstorm can't sustain itself. These downbursts are potentially damaging to aircraft flying within them. The craft can lose their lift or can be damaged in windshear.
CLASSIFICATION OF THUNDERSTORMS Thunderstorms come in four varieties. These are called single-cell storms, multi-cell storms, squall lines, and supercells. The simplest among these are single-cell storms,
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