A devastating F5 struck Fargo, North Dakota, as part of a tornado family. The twister was widely documented due to the highly populated area that was impacted. Hundreds of homes and other structures were destroyed, and at least 10 people were killed. Dr. Fujita (founder of the F and EF scale to rank tornado intensity) studied the aftermath of this tornado extensively. His examination of the twister and its parent storm led to the development of several new terms, including “wall cloud”, “collar cloud”, and “tail cloud.” A wall cloud is a lowering from the base cloud that is rotating and is what storm spotters look as they are in the field. 
