GRAND RAPIDS, MICH. - Several viewers contacted WZZM to ask about some unusual sights in the sky. We did a bit of research to learn they are called Fallstreaks.
According to the National Weather Service a fallstreak hole is also known as a "hole punch cloud" and it's easy to see why from this photo provided by Nicholas LaBelle who was in Sparta on Friday when he snapped a picture.
Here's more from the NWS: "A fallstreak hole is a large circular or elliptical gap that can appear in cirrocumulus or altocumulus clouds."
You might be wondering how they form and why: "High to mid level clouds, such as altocumulus, are often composed of tiny water droplets that are much colder than freezing, but have yet to freeze. These "supercooled" water droplets need a "reason" to freeze, which usually comes in the form of ice crystals. Planes passing through the cloud layer can bring these ice crystals."
"Once the ice crystals are introduced, the water droplet quickly freeze, grow and start to fall. A hole is left behind, which will start to expand outward as neighboring droplets start to freeze."
Click here for a link to the National Weather Service website explanation.
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