Hole Punch Clouds South of Wenatchee - February 28, 2010

On the afternoon of February 28th, Howard Lowell took these cloud pictures from Wenatchee, facing to the

southeast. The obvious question is: what is causing the clouds to look like this? The unofficial name of this

phenomena is "Hole Punch" Clouds. If you use your favorite web browser and search for this phrase, you'll

find lots of web sites and photos.

The exact cause of these cloud formations is still a bit speculative. But the generally agreed upon theory

is this: Clouds are typically formed when air ascends, since it cools and the moisture in the air condenses

into cloud droplets. The Hole-Punch clouds are caused by descending air, which typically causes clouds to

dissipate. The cause of the descending air is thought to be from a higher cloud, or possibly from the exhaust

of an airplane traveling above the cloud. In the picture below, you can even see some of what appears to be

virga (precipitation that evaporates before reaching the ground), the gray wisps just below and to the left of

the street lamp. This lends to the idea that the air in this "hole" is descending.

This picture actually shows the presence of another hole-punch cloud on the left-hand side of the picture near

the mountains. This appears to have more of a hole in the clouds than the larger hole-punch cloud in the center of the picture.

So, can you see these on satellite pictures? The answer is yes. The image below shows 2 "holes" just south of

Wenatchee, and another to the east of Yakima. Click here to see an animation of the satellite imagery.