Answer to Question 1
ANSWER: The Central Plains region is most susceptible to tornadoes because it often provides the proper atmospheric setting for the development of the severe thunderstorms that spawn tornadoes. Over the Central Plains (especially in spring) warm, humid surface air is overlain by cooler, drier air aloft, producing a conditionally unstable atmosphere. When a strong vertical wind shear exists (usually provided by a low-level jet and by the polar jet stream) and the surface air is forced upward, large supercell thunderstorms capable of spawning tornadoes may form.
Answer to Question 2
ANSWER: The first stage is the dust-whirl stage, where dust swirling upward from the surface marks the tornados circulation on the ground and a short funnel often extends downward from the thunderstorms base. Damage during this stage is normally light. The next stage, called the organizing stage, finds the tornado increasing in intensity with an overall downward extent of the funnel. During the tornados mature stage, damage normally is most severe as the funnel reaches its greatest width and is almost vertical. The shrinking stage is characterized by an overall decrease in the funnels width, an increase in the funnels tilt, and a narrowing of the damage swath at the surface, although the tornado may still be capable of intense and sometimes violent damage. The final stage, called the decay stage, usually finds the tornado stretched into the shape of a rope. Normally, the tornado becomes greatly contorted before it finally dissipates.
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