A rare classification of warning from the National Weather Service, the PDS or Particularly Dangerous Situation, is a weather alert many are unfamiliar with.
It's estimated at least 250 people died in Michigan's most extreme weather event, a massive storm on the Great Lakes known as "The Great Storm of 1913" or "The White Hurricane".
Halloween is just a week away, and as the excitement builds for a night of fun and frights, there's still some uncertainty about whether the weather will be a trick or a treat.