Temperatures plummeted in Michigan on Monday, October 30, dropping snow pellets known as graupel in parts of the state, video shows.Footage taken by Stephanie Bidock shows graupel falling on Highland Charter Township, located in the suburbs northwest of Detroit.Graupel occurs when cold water freezes onto already formed snowflakes as they fall, according to the National Oceanic and Atmospheric Administration.Cold temperatures would persist into Tuesday, the National Weather Service (NWS) said. Credit: Stephanie Bidock via Storyful