Why Is There A Hole In That Cloud?

Hole punch clouds, also known as fallstreak holes, are one of the most unique clouds there are.

And they couldn’t happen without people.


What You Need To Know

  • Hole punch clouds look like something punched a hole in a cloud
  • The atmospheric conditions have to be perfect to get a hole punch cloud event
  • The key ingredients in a hole punch cloud are super cooled water droplets and an airplane

In my nearly 30 years as a meteorologist, I’ve crossed many events off my weather bucket list, like seeing the northern lights, experiencing a blizzard, tracking a tornado and feeling below-zero temperatures. But, I’ve never seen a hole punch cloud.

Any time I see pictures of them appear on social media, I’m fascinated. They are so special and unusual. 

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Here’s how these clouds develop. The holes form in mid to upper level clouds such as altocumulus. These clouds are made up of tiny water droplets that are colder than 32 degrees.

These droplets don’t freeze because they don’t have any surfaces like dust, pollen, pollution or ice cyrstals to form on.

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When planes fly into these supercooled droplets they cause the air to expand and cool further. This supercooling is enough to turn the water to ice.

Once this process begins, a chain reaction starts and a large area of the cloud’s droplets turn to ice, fall and evaporate. 

When the ice is done evaporating, blue skies remain and there is a hole in the cloud. So keep looking up and maybe one day, you’ll spot one of these hole punch clouds.