Identifying the virgacloud feature
A cloud feature given to precipitation that evaporates in the air before reaching the ground
The ‘virga’ cloud feature can be found amongst seven cloud types: cirrocumulus, altocumulus, altostratus, nimbostratus, cumulonimbus, cumulus and stratocumulus. Translated from latin, meaning rod, the seven types of virga clouds are respectively abbreviated as ‘Cc vir’, ‘Ac vir’, ‘As vir’, ‘Ns vir’, ‘Cb vir’, ‘Cu vir’, and ‘Sc vir’. Virga cloud formations are essentially rain and precipitation strips falling from a cloud that evaporate before hitting the ground.
Virga is created when precipitation drops from a cloud and passes through a layer of dry air and evaporates. Interestingly enough, there are instances where virga will be picked up on radar under the assumption of light precipitation, but weather gauges on the surface won’t pick up any measurable precipitation. Virga can also be found on the leading edge of an approaching rain or snow shower.
Virga looks like cirrus cloud wisps falling from the base of other clouds. Clouds exhibiting virga can also go by the name jellyfish clouds. You also might hear virga be interchanged with the term fallstreak (hence the term fallstreak hole).
The shape of falling virga is sculpted by the intensity of the wind in the layer of air that it falls through. Virga is more common in relation to other cloud features, especially in desert environments where cloud bases are higher and the air is dryer.
