When we study logic in high school philosophy, the same example is often given: “It rains, then the streets get wet.” It’s kind of a no-brainer, right? Well yes, most of the time it is, but the truth is that there is a type of rain that does not wet the ground, because the water never touches it. It is something known as virgaalthough, due to their appearance, there are also those who mention them as jellyfish clouds
The latter is a good name, since it basically looks like a jellyfish that lets its watery tentacles fall to a certain height at which they disappear, without touching the ground.
Virga can form almost anywhere. However, this type of rain that does not wet is more common in desert regions, on coastal plains and also at high altitudes. It is a beautiful sight, but a nightmare for airplane pilots, as it can generate great turbulence. Now, why exactly do they occur?
Virga, the rain that does not wet
The virga begins as normal rain. That is, the air loaded with water is heated and rises in the form of vapor. In the highest layers of the atmosphere, it cools, so that vapor condenses to form liquid water in the form of droplets, which give rise to clouds. And finally, when the cloud is well loaded with water, it falls downwards, giving rise to rain.
Rain that does not wet is exactly the same; but, in its fall, the water encounters a layer of dry or hot air that transforms it back into steam. That’s why she never touches the ground.
Why is it dangerous for airplanes?
In this process in which the water droplets heat up and evaporate, the air around them cools. This is because the evaporation process requires heat, which is extracted from the surrounding air. Then, that cold, heavier air suddenly falls downward, causing gusts and turbulence, which can make the flight of airplanes very difficult.
In which clouds and when does the virga form?
This rain that does not wet generally comes from clouds of type cirrocumulus, altocumulus, altostratus, nimbostratus, cumulonimbus, cumulus and stratocumulus.
It is also known as ghost rain, for obvious reasons, and it is a very beautiful sight to see, as long as you are not traveling on a plane. Above all it is spectacular when it happens at sunsetsince its reddish light makes the gusts of air and branches of water that fall downward more visible, but never land on the earth’s surface.
As for the time of year, they can occur in any season, although they are much more typical during summer storms. In fact, they are more common than we might believe, the problem is that sometimes they go unnoticed. Maybe, even if we keep our feet on the ground, we should look up more. There may be shows there that we are missing.