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".
Heat is the leading weather-related killer in the United States, killing more people than any other extreme weather event. However, that's not case for Michigan.