1975 Omaha tornado outbreak
Three people were killed and 133 reported injured. One of the fatalities was thrown by the tornado from her home to a backyard four or five houses away. Debris was found miles away. Over 4,000 buildings were damaged and 287 were destroyed. In terms of damage, it was the costliest tornado in American history to that date, with damages costing at least $250 million to $300 million (around $1.7 billion in 2015 dollars), and insurance costs estimated at up to $1.1 billion (in 1975). It was the third-costliest tornado, behind the Oklahoma City-area F5 tornado on May 3, 1999, and the Wichita Falls, Texas, tornadoes on April 10, 1979, until the Joplin, Missouri EF5 tornado on May 22, 2011. It is now currently the seventh-costliest tornado on record.
Emergency communication system
161 people were killed and at least 990 injured when an EF5 multiple-vortex tornado hit Joplin, Missouri. Because Joplin is located in a tornado-heavy area of the country, many people considered the tornado sirens routine and ignored them. Instead, many residents waited until they received confirmation from another, non-routine, source, such as seeing the tornado, a radio or TV report, or hearing a second siren. In the aftermath, an assessment team recommended that emergency warnings take risk perception into account to convey a sense of urgency. NOAA Officials are considering ways to change the warning system to distinguish smaller tornadoes from more deadly ones.