Transcription: Thunderstorms are the most common type of storms. As many as 50,000 thunderstorms occur throughout the world each day. They develop from tall, puffy cumulonimbus clouds. Strong air currents inside these clouds force water vapor to move up and down at high speeds. The water vapor condenses quickly and causes heavy rain. The rapid motion of the air in these clouds builds up electrical charges. These charges cause lightning. The heat from a lightning flash rapidly expands the surrounding air creating sound waves that we hear as thunder.
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