Hole Punch Clouds
January 22, 2017

holepunchcloud_2

Dan Gregoria, NWS San Diego, Huntington Beach, CA

A few years ago I went to a weather conference and one of the more fascinating talks was on Hole Punch Clouds.  Meteorologists know that these “holes” in the clouds are created by airplanes.  The speaker explained that the latest research shows they are created by the propellers of airplanes not engine combustion.

holepunchcloud

Courtesy: Sean Browning, KNBC Photographer, Burbank, CA

Here is how they form:

The first requirement is the clouds have to be vertically thin.  The temperatures beneath the wings of a C-130 (seen below) are 14 degrees warmer than the surrounding environment.  This temperature difference and propeller motion creates a dry punch of air falling from the sky evaporating the clouds beneath.  This is always the case but if the clouds are too thick or the plane is above 20,000 feet a hole will not occur.  This is why Hole Punch Clouds are fairly rare to see.  But when you do get to see them, like Saturday, it’s an incredible sight!

c130

If you have pictures to share, I’d love to see them.  Tweet or Facebook me @anthonynbcla

To see other hole punch clouds from Saturday, click here: Hole Punch Clouds

 

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Hole Punch Clouds
December 21, 2011

 

Earlier this year I went to a weather conference and one of the talks was on hole punch clouds.  The latest research shows they are not created by engine combustion at all.  The first requirement is the clouds have to be vertically thin.  Researchers then discovered that the clouds usually form beneath C-130 planes (shown below).  Beneath the wings of these planes temperatures were around 14 degrees warmer than the rest of the plane and surrounding environment.  This temperature difference created a dry punch of air falling from the sky evaporating the clouds beneath.            

On a side note, a big thanks to Stephen Kornblitt who took this picture and sent it to Frank Billingsley.  A lot of people said it looked photo shopped but our engineers at the station said it was authentic.  Most hole punch clouds are circular.  This one is unique because it looks like an outline of a plane or the state of Texas. 

To view past weather quiz answers click here:

Past Weather Quiz Answers

Hole-Punch Clouds
July 28, 2010

 

If jet aircraft climb or descend under certain atmospheric conditions, they can inadvertently “seed” mid-level clouds.  Through this process aircraft leave behind holes or channels in the clouds.  The key is water droplets in the clouds have to be below five degrees Fahrenheit.  As air is cooled behind aircraft the water droplets freeze and drop toward earth creating what are known as hole-punch or canal clouds.  To read the complete article click here:

Hole Punch Clouds

To view other weather quiz answers click here:

Past Weather Quiz Answers