Definition: Virga is a form of precipitation that evaporates before it hits the ground. Low humidity and high temperatures can cause rain to evaporate completely shortly after its release from a cloud. Desert areas often have clouds showing virga. In fact, the precipitation often starts out in the form of ice crystals and never reaches the ground.
In the image to the right, the streaks of cloud-like material underneath the main cloud are virga. (Dry thunderstorms are those that produce virga.) A cloud that produces thunder, lightning, and rain are common in the western United States, but these clouds often do not have measurable ground-level precipitation. These dry thunderstorms are often culprits in creating massive wildfires as lightning ignites a dry fuel source on the ground during fire weather season (Usually in the hot summer months).
It is also theorized that virga are partially responsible for creating hole-punch clouds. In addition, virga high in the atmosphere can reflect sunlight creating brilliant sun pillars and other atmospheric optics associated with sunlight.
Also Known As: Fall streaks, or fallstreaks of precipitation
Common Misspellings: verga
