Rain That Doesn T Hit The Ground. Virga may look like a rain shower on radar but an observer will see a streak or shaft of precipitation falling from a cloud noticeably dissipating before ground level. Usually rain can start to fall in relative humidity values around 50 percent but the drops will be very small and will evaporate quickly when they hit the ground.
In fact, minuteearth explains, most rain never even reaches the ground. Sometimes instead of rain, all we get is virga — rain that evaporates before it hits the ground. Ensure that the trench is sloping away from the.