Virga

Common card · No. 232905

A virga, also called a dry storm, is an observable streak or shaft of precipitation that evaporates or sublimates before reaching the ground. A shaft of precipitation that does not evaporate before reaching the ground is known in meteorology as a precipitation shaft. At high altitudes, precipitation falls mainly as ice crystals before melting and finally evaporating. This is often due to compressional heating, because air pressure increases closer to the ground. Virga is very common in deserts and temperate climates. In North America, it is commonly seen in the Western United States and the Canadian Prairies. It is also very common in the Middle East, Australia, and North Africa. Virgae can cause varying weather effects because as rain is changed from liquid to vapor form it removes significant amounts of heat from the air due to water's high heat of vaporization. Precipitation falling into these cooling downdrafts may eventually reach the ground. In some instances these pockets of colder...

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