Fallstreak holes

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Fallstreak holes are large circular gaps that can appear in cirrocumulus or altocumulus clouds. The holes are formed when the water temperature in the clouds is below freezing but the water has not frozen yet. Due to not completely understood processes this water will remain in a liquid state almost indefinitely. When a portion of the water does start to freeze it will set of a domino effect causing the water vapor around it to freeze and fall to the earth as well. This leaves large circular holes in the cloud.^[1]