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.
Joplin High School
On May 22, 2011, a tornado that killed 161 people in Joplin extensively damaged the high school and Franklin Tech. The high school's graduation ceremonies had just taken place about three miles away on the Missouri Southern State University campus shortly before the tornado struck.
According to principal Kerry Sachetta, "You see pictures of World War II, the devastation and all that with the bombing. That's really what it looked like. I couldn't even make out the side of the building. It was total devastation in my view. I just couldn't believe what I saw." In the weeks after the tornado, it was determined that the campus was irreparable and would need to be completely rebuilt. 
Planning for a temporary school began four days after the May 22 tornado. School officials announced in June 2011 that juniors and seniors in the 2011-12 class (and possibly later) would attend classes in a section of Northpark Mall. Classes began in the renovated former Shopko location as scheduled on August 17, 2011.