1947: An estimated F5 tornado struck Woodward, Oklahoma during the late evening killing 95 people in that town. This is the most deadly tornado to ever strike within the borders of the state of Oklahoma. The tornado was one to two miles in width at times and traveled at a speed of 50 mph. This storm killed a total of 167 people along its 221-mile path from Texas into Kansas, injured 980 others, and caused nearly ten million dollars damage.
Source: NWS Office in Norman, Oklahoma.
1953: The first radar image of a tornado was detected by radar equipment at the University of Illinois Airport at Champaign, IL. Studies of the radar pictures from that day showed that a tornado of significant size and intensity could be detected.