Cloudburst is a sudden heavy rain falling for a short period of time in a small area. Cloudbursts are usually associated with thunderstorms. They occur most often in desert and mountain regions, and in the interiors of continents, such as the Great Plains of the United States. The uprushing air currents of a thunderstorm support a large amount of water in the form of raindrops. If the air currents suddenly lessen, the mass of rain quickly falls out over a small area. Stream beds become torrents, and rivers quickly rise in valleys. During a cloudburst, more than 1 inch (2.5 centimeters) of rain may fall in 15 minutes. See also Cloud ; Rain ; Thunderstorm ; Weather .
