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Basic Cloud Types

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Cloud Spotting Games

Next time you have nothing better to do, go be a kid again and look up at the clouds and see what shapes and animals you can find in the sky.  Just this time around, add a little twist to it and see if you can also identify which of the main families the cloud belongs to!

While there are a lot of different cloud types listed below, there are just a few basic ones I want you to be familiar with and be able to identify.

Stratus

Solid, yet still thin.  Not much vertical development.  Constant light rain can be expected.

Cirrus

High altitude and wispy thin clouds.

Cumulus

The “popcorn” you see in the sky in the summertime.  Indicative of an unstable atmosphere, turbulence below them, and the possibility for them to grow and become thunderstorms later on (cumulonimbus)

cloud types online pilot course

note: adding “nimbus” just means rain.  You can have a towering cumulus cloud or regular cumulus cloud for that matter.  However, it does not become “cumulonimbus” until rain begins to fall from it.

FAMILIES of clouds refer to the height they are at.  Clouds are divided into four FAMILIES based on their height.

  • High (cirro prefix)
  • Middle (alto prefix)
  • Low
  • Clouds with extensive vertical development (i.e. towering cumulus)

 

VIRGA

Sounds pretty, right?  It looks even prettier, check out the picture below!

virga weather pilot ground school

As with many beautiful looking things in this world, it is in fact totally vicious and will get you killed.  What we see here is rain falling and evaporating before it ever reaches the ground.  Not only is the rain cooling the air around it making it want to sink (because it is carrying cold water droplets from up above).  Since the rain is evaporating before ever reaching the ground, it is absorbing a large amount of heat energy in that process of evaporation.  This means the air around and below this evaporating rain is going to start sinking very, VERY fast.

Ever feel a cold strong wind when the sky looked stormy, only to never really ever have any rain reach the ground?  This was probably just a downdraft coming from a nearby cell of VIRGA.  Downdrafts should be obviously hazardous to you as a pilot for two reasons, horizontal windshear, and vertical windshear.  If you are unlucky enough (or unwise enough) to fly near one of these cells as it begins producing large downdrafts, the vertical “wind” will push you down toward the ground much faster than your airplane can climb (at speeds up to 6,000 fpm sink, most Cessna’s only climb at 500-750 fpm).  As you get near the surface or not directly underneath the cell, you will now get the displeasure of horizontal windshear (reference the diagram below) that will lead to large fluctuations in airspeed and if you are especially unlucky, large enough increases to cause structural damage or large enough decreases to cause a stall.

downdraft windshear