Michigan fallstreak cloud
© Nicholas LaBelle via WZZM-TVThis fallstreak hole was captured by Nicholas LaBelle while he was in Sparta on Friday
Several viewers contacted WZZM-TV to ask about some unusual sights in the western Michigan sky. The TV station 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 this pic.

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."