WACH (Columbia, SC) — Did you happen to see these clouds around the Midlands on Monday morning?
They are called hole punch or fall streak because of the gap left behind.
These are typically formed out of altostratus or altocumulus clouds. Under the right circumstances these mid-layer clouds can be made up of supercooled water droplets.
Supercooled just means that the water droplets are below freezing, but haven't actually turned to ice yet. In order for ice crystals to form, they typically need something to start, an ice nucleus. This can be a single ice crystal, pollen, ash, all sorts of things can get the process started.
When a plane flies through a cloud deck like this it can introduce ice to the cloud from it's contrail.
This starts off a chain reaction of more ice crystals forming. Some will fall out of the cloud and evaporate and other water droplets will evaporate on their own.
This leaves behind a hole or canal in the main cloud deck and often shows some of the ice or cloud dropping out of the middle of it.