Virga
Virga
- Virga is precipitation that falls from a cloud but evaporates or sublimates before reaching the ground. It is falling rain, snow, or ice crystals whose path ends in the air, so an observer below sees precipitation without wet ground.
What it looks like
- Virga hangs from a cloud as streaks or wisps, often like trails beneath a clump or layer. Their shape records where precipitation is falling through the atmosphere, while the surrounding air removes it before it reaches the surface.
- Trails of liquid droplets beneath low clouds tend to look grey. Ice-crystal trails from middle or high clouds tend to look pale, though the same virga can look lighter or darker against different skies.
Where it fits
- Virga names the precipitation's failure to reach the ground. When visible precipitation does reach the surface, the cloud feature is called praecipitatio.
- A fallstreak hole is a related case: falling ice crystals leave a clearing in a layer of supercooled droplets.
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