Did anyone die in the Joplin tornado?

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.

Emergency communication system

An emergency communication system (ECS) is any system (typically computer-based) that is organized for the primary purpose of supporting one-way and two-way communication of emergency information between both individuals and groups of individuals. These systems are commonly designed to convey information over multiple types of devices, from signal lights to text messaging to live, streaming video, forming a unified communication system intended to optimize communications during emergencies. Contrary to emergency notification systems, which generally deliver emergency information in one direction, emergency communication systems are typically capable of both initiating and receiving information between multiple parties. These systems are often made up of both input devices, sensors, and output/communication devices. Therefore, the origination of information can occur from a variety of sources and locations, from which the system will disseminate that information to one or more target audiences.

An emergency notification system refers to a collection of methods that facilitate the one-way dissemination or broadcast of messages to one or many groups of people with the details of an occurring or pending emergency situation. Mass automated dialing services such as Cell Broadcast,Reverse 911, as well as common siren systems that are used to alert for tornadoes, tsunamis, air-raid, and other such incidents, are examples of emergency notification systems.

Emergency communication systems often provide or integrate those same notification services but will also include two-way communication—typically to facilitate communications between emergency communications staff, affected people, and first responders. Another distinguishing attribute of the term "communication" may be that it implies the ability to provide detailed and meaningful information about an evolving emergency and actions that might be taken; whereas "notification" denotes a relatively more simplistic one-time conveyance of the existence and general nature of an emergency (such as Emergency Rescue Location).

Since there are a collection of related systems used in diverse settings in varying ways, there are numerous terms that are used interchangeably among the entities that use or have a need for emergency communication systems. In most instances, though, these are all used to refer to the same or substantially similar concepts. For example, use of the terms “emergency communications” and “disaster communications” definitively refer to the same concept, with the only potential difference lying in the connotation or emotional meaning.

Emergencies place demands on communication processes that are often significantly different from the demands of non-emergency circumstances. Emergencies often involve escalating and evolving events that demand high performance and flexibility from the systems that provide emergency communication services. Message prioritization, automation of communication, fast message delivery, communication audit trails, and other capabilities are often required by each unique emergency situation. Inadequate emergency communications capabilities can have consequences that are inconvenient at best and disastrous at worst.

Depending on the location, time, and nature of the emergency, a large variety of limitations could present themselves when it comes to communicating details of an emergency and any resultant actions that may need to be taken to protect life and property. For example, an audio public address system might be rendered ineffective if the emergency happens to be an explosive event which renders most or all of those affected deaf. Another common example might be the limitation of a fire alarm's siren component in a deaf school. Yet another example of a limitation could be the overloading of public services (such as cellular phone networks), resulting in the delay of vital SMS messages until they are too late, such as occurred during the Boston Marathon bombing.

Emergency systems require timely and quick dissemination in order to mitigate damage or loss of life. During the Virginia Tech massacre, about two hours had passed before the first communication (an email) was sent to staff and students. By that time, the gunman had already entered and secured a building in which he was shortly to begin his attack. It wasn't until about 20 minutes after the shootings began that a loudspeaker announcement was made for people to take cover.

During a crisis, the people who use an ECS need to quickly and easily launch their notifications and they need to be able to do so in a way that securely provides them with confidence and an intuitive, familiar and easy-to-use interface that can be accessed from any location. An emergency communication system that's designed for non-technical users will ensure successful administration and usage; and during some life-threatening emergency situations, campus administrators must be able to react quickly and trigger the alert system swiftly. Yet emergency alert is probably among the least used and least familiar processes. Ease-of-use therefore is critical to the effectiveness of an emergency communication system.

However, in order to support a robust and capable emergency communication ability, this ease of use should not preclude the use of a complex, technologically advanced system. A sufficiently advanced system is required to coordinate multiple components to act in concert, to initiate and propagate emergency communications in any manner of ways. A distinguishing factor is when such a system includes these advanced capabilities, while still being easy for the user to operate. This is important not only for effective emergency communication, but also for an organization to realize the most return on investment, as well as the user being familiar enough with its operation as to effectively operate it under stressful emergency situations, such as in an earthquake or tsunami.

A clearly needed attribute of any modern emergency communication system is the ability to not only provide notification of an emergency, but to also provide clear and actionable instructions for how to respond to an emergency. In a study by the Rehabilitation Engineering Research Center for Wireless Technologies, it was revealed that regardless of the initial form of notification, a secondary form was necessary before action would be taken. This supports the important observation that providing clear and concise instructions may reduce dependency on such secondary verification; and thus, providing instructions may save lives in an urgent emergency situation.

Emergencies often require delivery of different versions of the same communication at the same time. For example, in an armed hostage-taking incident, occupants of a building may need to receive instructions to lock and barricade the door until further notice, while first responders to the incident need to be aware of the lockdown instructions and be provided more specific details of the hostage-taking event to inform their actions.

Using the hostage-taking example, some of the more modern emergency communication systems such as AlertMedia or EverBridge state the ability to deliver a single message that provides full details to first responders, while filtering that same message to provide more limited instructions to different groups. For example, a specific message could be sent to people in a certain area, in a specific building, or even in a specific department. By using a single message that segregates information between types of users, fewer messages have to be created and sent, which can also save time.

There should be multiple means of delivering emergency information so that if one fails, others may get through. Also, according to the Partnership for Public Warning, research shows clearly that more than one channel of communication will be consulted by people at risk in order to confirm the need for action. The public expects to be contacted in a variety of ways. As evidenced by various historical and recent events, besides phone calls and emails, citizens also expect to be able to use and be reached via text messaging, and fax. In one exemplary incident, the 2012 Wisconsin Sikh temple shooting, barricaded victims relied on sending text messages for help, in addition to traditional phone calls. In addition, the public may look to social media as another vehicle to receive messages and check in on updates.

Additionally, the Partnership for Public Warning states, “A single warning is frequently insufficient to move people to action, especially if it cannot be confirmed by direct observation. For most people the first warning received captures their attention and triggers a search for corroboration, but cannot be relied on to elicit the desired behavior. Scientific research supports the common-sense observation that people are disinclined to risk being fooled by a single alarm that might prove false or accidental. Effective warning requires the coordinated use of multiple channels of communication.”

To support these attributes, a "unified" emergency communication system should be able to connect to and communicate with other related systems, hence the term. According to the Partnership for Public Warning, a fundamental problem is the lack of technical and procedural interoperability among warning originators, system providers, delivery systems, and warning recipients. Originators of warnings must undertake expensive, redundant tasks using multiple, dissimilar tools and techniques to take full advantage of today's warning systems.

Also, there are multiple ways that an emergency communication system might obtain an original warning. One example of this might be the case of a building's fire control system dispatching a notice that a smoke detector has activated. A properly designed emergency communication system should be able to receive that notice and process it into a message that the building's occupants can understand and take action on in order to save life and property. Another example might be of the National Weather Service sending an EAS severe weather warning (e.g. via RSS feed or similar). Modern emergency communication systems include the capability to subscribe to such source feeds, so that those responsible for disseminating the message have the most up-to-date information.

The ability to interoperate should also consider the need to be both forward and backward compatible with older and yet-to-be-conceived technologies. Introduction of a system that cannot interoperate with previously deployed equipment creates potentially serious barriers to effective operation.

Because of budgetary constraints, for many organizations, the affordability of an emergency communication system can be just as important as the system's capabilities and effectiveness. The purchase and installation of enough emergency communication devices to provide multiple methods of communication to many locations within an organization in order to deliver location-specific instructions and for redundancy can be very expensive. Many organizations, therefore, are looking for more economical emergency communication solutions. Some all-in-one devices, such as Advanced Network Devices' PoE (Power over Ethernet) devices, which save costs in combining multiple features in one device, installation, and operation. Overall, the more affordable it is to procure, install, and maintain an emergency communication system, the more prolific such systems may become, and the more prolific these systems are, the more likely it is that these systems will be available to aid in times of emergency in more locations. According to Federal Signal, beyond supporting emergency response, today's mass notification systems have proven to be a valuable asset for everyday, non-emergency, intra- and inter-plant communications. This has become particularly evident in the deployment of interoperable, multi-device communications technology that not only enhances overall plant communications, but provides a host of useful software-based management and administrative tools. Additionally, many of the more traditional approaches to mass notification, i.e., public address and intercom systems, e-mail, and voice and text messaging, provide everyday functionality for plant communications and process control that represents attractive potential for return on investment.

An emergency communication system may be composed of a product and its associated hardware and software, as owned by the entity using it (e.g., an on-site paging network), or as a service owned and provided by a third-party (e.g., a cellular carrier's SMS network). Each have their own advantages and disadvantages; however, despite perception otherwise, services have some major inherent problems when it comes to effective emergency communications. For instance, using SMS as one example, due to the architecture of cellular networks, text messaging services would not be able to handle a large volume of communications in a short period of time, making this particular type of service a potentially ineffective emergency communication method.

Premises based emergency communication systems are those which primarily or wholly exist in the same geographical or structural area as it serves, while non-premises based emergency communication systems are those which exist in a different geographical or structural area. There are advantages and disadvantages of each. Often, non-premises based systems are slower than those that are premises-based, because at the very least, the different locations need to be connected via (usually public) data networks, which may be susceptible to disruption or delay.

With the growth of populations and the evolution of technology, the methods for communicating emergency situations have also changed, as has the definition for what might constitute an “emergency.” These methods would also very likely depend on a particular region's culture and location, as well.

In America's formative years, common means of emergency communications may have mostly consisted of church bells being rung or messengers on horseback. Later, as technology developed, the telegraph became a nearly instant method of communicating. From there, radio communications, telephones and sirens became commonplace.

After the surprise attack on Pearl Harbor, by the Japanese in 1941, Civil Defense sirens became popular and resulted in their widespread use in military bases and towns across America. A particular weakness of these systems is that they largely lack the ability to inform people what they should do.

Fire alarm systems were first developed around the late 1800s and other related life-safety detectors associated with those systems (e.g., duct detectors, heat detectors, etc.) were developed around the early 1900s. These constitute the first automated systems used in public and private buildings that are in normal and widespread use today. These systems, although originally designed for fire, have also been used for many other types of emergencies, sometimes effectively and sometimes not. For instance, if a fire alarm has been activated (as a general warning device) during an active shooter incident, the typical reaction to evacuate may not be the safest course of action; instead, a shelter in place action may be better. As an example, during the 2012 Aurora shooting, a mass shooting event that happened at the Century 16 movie theater in Aurora, Colorado, the assailant began targeting victims as they attempted to exit the theater; in which case, it would have been unwise to heed the fire alarm, that was sounding, and evacuate.

Today, modern communication tools such as smartphones, flat-panel digital signage, GPS, and text-to-speech (among many others) are changing the way in which people are notified about emergencies. Of added value, with these more modern tools, is the ability to provide more specific instructions. Now, instead of merely notifying people about an emergency, it is possible to provide specific instructions on what to do in order to mitigate the effects of an emergency. Furthermore, those instructions might even be customized for those peoples' specific and unique circumstances. For example, smart-phones may have geo-location abilities that would allow a map to be shown of safe locations (and perhaps routing there-to), relative to those devices' specific users — all with a singular alert being sent as the source of those warnings. Modern implementations directed at personal devices allow for acknowledgement of receipt. This way emergency services can gain insight on message reception and tally users that have reached safety.

Perhaps the oldest or most basic forms of public communication are staples such as over-the-air television, sirens, and radio. More modern components (using the same concept) might include lights and Giant Voice systems. These all have one thing in common: they broadcast indiscriminately to anyone who has the means to receive the message; whether they are simply in the immediate area or require some sort of receiving device.

Broadcast technologies use point-to-point communications methodology and may either require infrastructure or not. Examples of broadcast technologies requiring infrastructure might include such things as Reverse 911 and broadcast-affiliate networks.

Broadcast technologies that do not depend on man-made infrastructure to convey communication may be least susceptible to disruption during disasters and emergencies. Some examples of infrastructure-independent technologies are:
Each device has its own pros and cons given the emergency situation.

Broadcast technologies that depend on man-made infrastructure to convey communication are susceptible to disruption if any part of that infrastructure is overloaded, damaged or otherwise destroyed. Some examples of infrastructure-dependent technologies are:
"Wireless Mobile Telephony (WMT) PA Systems" refers to PA paging and [intercom] systems that use any form of Wireless Mobile Telephony System such as GSM networks instead of a centralized amplifier to distribute the audio signal to paging locations across a building or campus, or other location. The GSM mobile Networks are used to provide the communication function. At the transmission end, a PSTN Telephone, mobile phone, VOIP phone or any other communication device that can access and make audio calls to a GSM based mobile SIM card can communicate with it. At the receiving end, a GSM transceiver receives these network transmissions and reproduce the analogue audio signal via a Power Amplifier and speaker. The work on this was pioneered by Stephen Robert Pearson of Lancashire, England who successfully applied for and was granted patents for the systems which incorporate control functionality in addition to the audio announcement capabilities. The use of the WMT (GSM) networks means that live announcements can be made from anywhere to anywhere in the world where there is WMT connectivity. The patents cover all forms of WMT i.e. 2G, 3G, 4G... xxG. A UK company called Remvox Ltd (REMote VOice eXperience) has been appointed under license to develop and manufacture products based upon this technology.
There are primarily two major types of communication devices: those for individual people and those for groups of people. Public Communication Devices are the devices that are designed to deliver a communication to more than one person as a single process at the same time. Examples include a digital electronic sign, a loud speaker that is part of a PA system, or a large flat panel display on a wall. A private communication device is a device that is designed to deliver communication to one person at a time through a single process. Typically, a single person is in control of such a device which is usually not shared. Examples include a cell phone, a text message on the cell phone, an email, or a message over a 2 way radio.

Public communication refers to the conveyance of messages to people, in such a way that anyone may receive the communication at nearly the same time as anyone else, typically using a common device. The most common way of facilitating public communications is by using devices that are incorporated into some public venue, such as public-address systems or digital signage. Using public devices for the purpose of public warning empowers people at risk to take actions to reduce losses from natural hazards, accidents, and acts of terrorism.

"Private" means the delivery of messages to a specific individual, in a private manner or in such a way that even those nearby may not get the message. Common ways of facilitating private communications involve devices such as telephones or electronic mail.During the September 11 attack in 2001, traditional telecommunications were stretched and overloaded. Phone networks along the entire East Coast were congested into uselessness. 911 operators were overwhelmed with calls and could do little more than offer encouragement because of the confusing information they were receiving. Communications between emergency services personnel were limited by a lack of interoperability between departments. Many fire-fighters died when the towers collapsed because they couldn't receive the warning that the police officers received from the New York City Police Department (NYPD) helicopters. Amateur radio played a large role in facilitating communications between the various emergency departments, which operated on different frequencies and protocols.
On the day of the 7 July 2005 London bombings, mobile phone networks, including Vodafone, reached full capacity and were overloaded by 10:00 a.m., only an hour and ten minutes after the bombs went off. Because of an antiquated radio system, the damaged trains were unable to communicate with the Transport for London control center or emergency personnel, while senior emergency services managers, of the London Ambulance Service in particular, were forced to rely on the already overloaded mobile phone network because of the lack of digital radios. The Access Overload Control, implemented only in a 1 km area around Aldgate Tube Station, wasn't helpful because many officials didn't have ACCOLC-enabled mobile phones. In the aftermath, the London Assembly determined the need for a digital radio communications system in London that can operate underground.

When Hurricane Katrina, a Category 5 hurricane, hit New Orleans, the emergency communications systems were completely destroyed, including power stations, internet servers, mobile phone towers, and 911 services. The Federal relief workers' satellite phones weren't interoperable, even when they did work. A few AM radio stations were able to continue broadcasting throughout the storm, notably WWL Radio, which remained on the air by broadcasting from a closet. Amateur radio was instrumental in the rescue process and maintained signals when 911 communications were damaged or overloaded.

The Virginia Tech shooting, which resulted in the death of 33 people, helped propel discourse for effective emergency communication systems in schools. Virginia Tech had systems already in place, including e-mail and text notifications, but lacked a cohesive plan for using them. No warnings were sent out until after the event, two and a half hours after the initial shootings. Virginia Tech has since updated its emergency communications systems, especially public ones, since students can't always check e-mail in a timely fashion and professors often request that wireless devices be turned off in class. Because the massacre occurred within a 10-minute period, other schools have also implemented new, improved emergency communications systems with an emphasis on speed of communication.

The Japan Meteorological Agency's (JMA) early warning system, which uses seismometers, was able to alert millions of people across Japan about the impending earthquake via radio, mobile phone networks, including Docomo, AU, and SoftBank, and television, including both NHK channels and cable channels. The tsunami warning system alerted people shortly after, although the tsunami was larger than expected. In areas with infrastructure still intact, even though both landline and mobile phone lines were not functioning as might be expected, the Internet was still accessible. In the hardest hit areas, particularly Sendai and other areas of Miyagi, Iwate, and Fukushima Prefectures, satellite phones were often the only form of communication that functioned reliably. The following nuclear disaster at the Fukushima Daiichi Plant was rife with communications problems. No communications plan was in place, internal communications were poor, external communications were slow, and the public quickly lost confidence in TEPCO and the nuclear industry. The primary criticism was a failure of the government to release accurate information about the disaster. Calls were made for more transparency and promptness with future events.

During the 2012 Aurora shooting on July 20, 2012, the gunman, James Eagan Holmes, released tear gas before opening fire during a showing of "The Dark Knight Rises", causing many of the moviegoers to mistake the attack for part of the film's special effects. According to preliminary reports, the suspect initially went into the theater as a patron. He then exited and propped open an emergency exit, while he went to his car to get his bulletproof vest and weapons. He then attacked after reentry through the propped-open door. In this type of situation, there could have been considerable warning. Technology exists that can warn about open doors (such as an emergency door that shouldn't normally be open), and can send clear warning and instructions to any number of devices, including a movie screen. There is also a significant opportunity to consider the use of the theater's fire alarm system. Shortly after the assailant began shooting, the building's fire alarms were sounded. The natural inclination, in response to a fire alarm, would be to evacuate the building, but in this case, the assailant was specifically targeting people who attempted to exit.

Hurricane Sandy hit New York City, New Jersey, and the surrounding area on October 29, 2012, destroying thousands of houses and leaving millions without electricity and thus without internet, mobile phones, or landline communications. To prepare for the hurricane, many areas provided additional emergency help lines in case 911 wasn't available, The Federal Emergency Management Agency has strengthened its ability to respond to a disaster since the communications problems during Hurricane Katrina and using Twitter in its rescue efforts, and amateur radio operators were on standby to provide emergency communications. In the aftermath, up to 25% of mobile phone towers, network providers, and television stations were powerless. Communications have been steadily improving, however, although the hardest hit areas are still experiencing serious power outages.

Hurricane Harvey hit the coast of Texas, causing devastation upon landfall and massive flooding in Houston after meandering through Eastern Texas over the course of four days. While organizations like the Salvation Army and American Red Cross contributed to the disaster relief process, H.E.B., a regional grocery chain, was also able to assist by using its emergency notification system to identify employees who were in need of assistance, and those available to help. H.E.B. was able to accomplish this by using its emergency notification system, AlertMedia, which it has used since 2017. H.E.B. deployed mobile kitchens and giant water coolers to the affected community in the days following the hurricane.

A gunman opened fire at Marjory Stoneman Douglas High School in Parkland, Florida, on February 14, 2018. The shooter pulled the fire alarm in order to lure students and staff members out into the hallways, which caused some confusion among students and staff members, because there had been a fire drill earlier that same day, and shortly after the shooting began, a staff member activated a code red lockdown. There was also confusion because of the contradictory instructions coming from the emergency communication system, the fire alarm instructing students to evacuate while the PA system instructed them to lock down and stay where they were. Seventeen students and staff members were killed in the shooting, and a further seventeen were injured. This incident prompted students to found Never Again MSD and demand firearm legislation from lawmakers.

The tornado outbreak sequence of May 21–26, 2011 was one of the largest tornado outbreaks on record which affected the Midwestern and Southern regions of the United States. Most of the tornadoes developed in a corridor from Lake Superior southwest to central Texas; isolated tornadoes occurred in other areas. An especially destructive tornado destroyed one-third of Joplin, Missouri, resulting in 158 deaths and over 1,000 injuries. The Joplin tornado is the deadliest in the U.S. since April 9, 1947, when an intense tornado killed 181 in the Woodward, Oklahoma area. Tornado-related deaths also occurred in Arkansas, Kansas, Minnesota, and Oklahoma. Overall, the tornado outbreak resulted in 184 deaths, 6 of those non-tornadic, making it second only to the 2011 Super Outbreak as the deadliest since 1974, and the second costliest tornado outbreak in U.S. history behind that same April 2011 outbreak, with insured damage estimated at $4–7 billion.

Tornado outbreak sequence of May 21–26, 2011

April 2011 was the most active month for tornadoes on record, capped by a very large tornado outbreak (the largest on record) that killed 324 people in the final week. In contrast, the first three weeks of May were remarkably quiet; only a few isolated tornadoes were confirmed. However, this pattern changed abruptly as a strong low-pressure area, associated dry line and cold front tracked eastward.

On May 21, a small system of thunderstorms developed in Brown County, Kansas while another system formed to the southeast of Emporia, Kansas. The Brown county system spawned a brief tornado over Topeka, Kansas, causing minor damage. This system also caused significant damage in Oskaloosa, Kansas, and other communities. Meanwhile, the Emporia system spawned an EF3 tornado that struck Reading, Kansas; one person was killed, several others were injured, and at least 20 houses were destroyed. These two systems developed several other tornadoes throughout the evening.

A moderate risk of severe weather was issued for much of the Midwest, as well as further south to Oklahoma for May 22. The first tornadic supercell developed in the mid-afternoon hours over the western Twin Cities in Minnesota, and caused moderate damage in the Minneapolis area. Shortly thereafter, an intense tornado crept towards Harmony, Minnesota, prompting the National Weather Service to issue the first tornado emergency of the outbreak. Late that afternoon, a large, intense EF5 multiple-vortex tornado left catastrophic destruction in Joplin, Missouri. Causing 158 fatalities, it was the deadliest single tornado in the U.S. since at least 1947.

Once again, a moderate risk of severe weather was issued on May 23—this time for the southern Plains and the lower Great Lakes. Forecasts showed that the main threats would be damaging wind and large hail instead of frequent tornadoes; the stationary front lacked the necessary wind shear to sustain the type of tornadic supercells seen on May 22. This prediction came to light, as only scattered, and mostly weak tornadoes were reported throughout the day. However, an EF2 tornado caused significant damage in Tennessee and Kentucky.

On May 24, a high risk of severe weather was issued for parts of south-central Kansas, central and eastern Oklahoma, and extreme north-central Texas; a moderate risk was issued for surrounding areas in those three states plus northwestern Arkansas and southwestern Missouri. Throughout this region, strong to violent tornadoes were considered to be highly probable for three reasons: (1) the stationary front was expected to maintain its position over the region, (2) wind shear was expected to greatly increase, and (3) these elements would be associated with an incoming trough. Late that morning, the tornado threat increased to 45%, a rare occurrence matching the widespread April 27 outbreak. At 12:50 p.m. CDT, the SPC issued a Particularly Dangerous Situation (PDS) tornado watch for parts of central Oklahoma, including Oklahoma City and northern Texas, in effect until 10:00 p.m. CDT. Numerous tornadoes touched down in several regions, with the first activity being in western Oklahoma that afternoon where several very intense tornadoes developed, including another EF5 (the sixth of the year). They did not cause extensive damage in Oklahoma City, but 11 deaths were reported among extensive damage just to the southwest of the OKC metro. Other tornado clusters developed in central Kansas that afternoon and in the Dallas-Fort Worth Metroplex that evening.

Once again on May 25, a high risk of severe storms was issued for the middle Mississippi River valley from near Memphis, Tennessee northward to north of Evansville, Indiana, and was expanded late that morning northward to near Indianapolis, Indiana, northwest to near St. Louis, Missouri, southeast to just west of Nashville, Tennessee and southwest to near Little Rock, Arkansas. Several hours before the outbreak was expected to begin, a PDS tornado watch was issued for western Kentucky, southern Indiana, the southern half of Illinois and eastern Missouri. The entire state of Indiana, southern Michigan, and most of Missouri were under tornado watches. Widespread tornado activity occurred that day across the central and eastern U.S. An EF3 destroyed many homes in the town of Bedford, Indiana, and an EF2 wedge tornado caused severe damage in Sedalia, Missouri.

Tornado activity continued on May 26, but most were weak. 8 separate EF1 tornadoes touched down across Pennsylvania. An isolated EF3 tornado destroyed multiple homes near Bush, Louisiana.

On May 22, a large, devastating EF5 tornado tracked through Joplin, Missouri, leaving behind catastrophic damage. It was a multiple-vortex tornado in excess of wide. Mainly the southern part of the city was affected with most structures in the area either damaged or destroyed. 162 people were killed along the path through Jasper and Newton counties in Missouri, making it the deadliest U.S. tornado since 1947, and one of the deadliest single tornadoes ever recorded. Among the most heavily damaged structures was St. John's Hospital (pictured right), which later was torn down due to the severity of the structural damage. Damages were estimated at around $2.8 billion (2011 USD).

During the early evening of May 24, a long-tracked, violent, EF5 wedge tornado touched down in southwest Hinton, Oklahoma and produced extreme damage in rural portions of Caddo, Canadian, Kingfisher, and Logan counties, killing nine people and injuring 161 others along a long path.
Shortly after touching down in Caddo County, the tornado quickly became violent, debarking numerous trees as it crossed into Canadian County southwest of Calumet, and crossed Interstate 40 west of El Reno, reaching maximum intensity. Three people were killed as two vehicles were tossed more than from the road and obliterated, the victims being found stripped of clothing from the interstate and left "unrecognizable". Only pieces of the vehicle's frames were reportedly recovered. A nearby oil tanker truck that was parked at an oil production site near the interstate was thrown approximately into a wooded gully. Several homes were swept completely away along Interstate 40, trees were completely debarked, and the ground was heavily scoured in some areas. At the nearby Cactus-117 oil rig site, a oil derrick was blown over and rolled three times. Due to the extreme nature of the damage at the Cactus-117 oil rig and along Interstate 40, damage in that area was rated EF5. The tornado passed north of El Reno and continued northeast, producing EF3 to EF4 damage in rural areas. The tornado then passed northwest of Piedmont as a high-end EF4, leveling multiple homes and causing additional fatalities. The Falcon Lake subdivision was particularly hard hit, and multiple homes and vehicles were swept into the lake. One home had nothing left but the foundation slab and an above ground reinforced concrete shelter, which sustained damage to its metal door from debris impacts. An SUV in this area was thrown into a wooded thicket, and had its frame torn from the vehicle body, which was found crumpled around a debarked tree. The frame was twisted apart and was found nearby, along with the engine block and axles. The tornado weakened to EF3 strength as it crossed into Kingfisher County debarking trees and heavily damaging structures. The tornado then weakened further to EF2 strength, with damage confined to outbuildings and trees. Crossing into Logan County south of Cashion, the tornado produced a mixture of EF2 and EF3 damage as large high-tension towers were toppled and manufactured homes were destroyed. Frame homes were left with only interior rooms standing in this area, and two people who were caught outside during the tornado were killed. EF0 to EF1 damage occurred along the north side of Guthrie before the tornado dissipated.

The mesonet station at El Reno recorded a wind gust of as the tornado passed by, which set a record for the highest wind speed observed by the Oklahoma Mesonet. University of Oklahoma (OU) mobile Doppler radar measurements recorded winds up to within the tornado as it crossed Interstate 40. This was the first EF5 tornado to strike Oklahoma since 1999, when an F5 tornado killed 36 people in and around southern and central parts of the Oklahoma City metropolitan area. Another violent tornado struck the El Reno area two years later on May 31, 2013 and also struck several storm chasers, three of whom were killed, in addition to a local resident that was following the storm.

As the EF5 El Reno–Piedmont tornado dissipated on the evening of the 24th, a separate supercell thunderstorm produced another violent tornado further to the south in Grady County.
The tornado touched down along the southwest side of Chickasha as a narrow cone shaped tornado, initially causing EF0 damage to roofs, trees, and fences. Continuing northeastward across the south side of town, the tornado reached EF2 strength as it struck a mobile home park, killing one person at that location. A car wash, automotive shop, gas station, and car dealership were damaged nearby. Several apartment buildings and a strip mall sustained major structural damage as the tornado exited town. The tornado destroyed outbuildings, snapped trees, and tossed farming equipment as it crossed U.S. Route 62 east of town. After crossing the highway, the tornado began to rapidly grow in size and intensity, reaching EF3 strength as homes lost their exterior walls and trees were debarked nearby. Several metal buildings and homes were destroyed at EF2 to EF3 strength along the south side of Friend Road. The tornado crossed the road and became large and wedge-shaped, reaching EF4 intensity, scouring the ground to bare soil, debarking trees, and leveling homes, one of which was reduced to a bare slab (though this home was nailed rather than bolted to its foundation). Several vehicles were thrown hundreds of yards nearby, including an SUV that was carried 300 yards and crumpled into a ball. The tornado maintained EF4 strength crossed E1340 Road further to the northeast, reducing two well-built homes to rubble and destroying two nearby metal buildings. Many trees were debarked in this area, and a mixture of scoured crops, mud, and straw was found piled up to a depth of 6 feet against a nearby fence line. A third home sustained collapse of its exterior walls. Further along the path, another well-built home was flattened at EF4 strength, a metal building was destroyed, and vehicles were thrown up to 300 yards away along Ballard Road before the violent tornado tore across a series of open fields further to the northeast, leaving behind a continuous swath of debarked trees and scoured grass. An oil pump jack was also destroyed in this area. The tornado weakened momentarily as it passed to the northwest of the Indian Ridge Golf Course, producing only EF1 tree damage. The tornado re-intensified as it crossed NW 25th Street, completely debarking numerous trees and obliterating several metal buildings, outbuildings, and mobile homes. Several vehicles parked near a residence along N2980 Road were thrown up to 400 yards away, some of which were wrapped around trees or stripped down to their frames, and severe ground scouring occurred in this area. Numerous homes were heavily damaged or destroyed in a nearby semi-rural subdivision, one of which was leveled at EF4 intensity.
The tornado then crossed into McClain County, tearing through residential areas along the north edge of Blanchard. According to NWS damage surveyors, the tornado "shrunk and tightened to plausibly EF5 strength" as it approached and crossed Kitty Hawk Road, scouring away a large area of pavement. Sections of asphalt were gouged out by high-velocity debris impacts further along the road, and nearby trees were reduced to completely debarked stumps. As the now narrow, but very intense tornado ripped through the front lawn of a nearby house, all grass and several inches of topsoil was scoured away in a narrow swath. Several homes were reduced to bare slabs in this area, and vehicles were thrown up to 600 yards away, including a pickup truck that was torn into multiple pieces. Due to intensity of the damage in this area, surveyors noted that the tornado was "plausibly EF5" as it clipped the north side of Blanchard, though the fact that the homes swept away were missing some of their anchor bolt washers led to a high-end EF4 rating being assigned instead. Just to the northeast, the tornado maintained its strength as it struck a steel-reinforced concrete dome home, which was shredded by flying debris and sustained partial cracking of its frame. Asphalt was scoured from the home's paved driveway as well. The tornado then weakened to EF3 strength as it crossed Sandrock Road, debarking trees and heavily damaging or destroying several homes in nearby subdivisions. Several cars were blown out from underneath a nearby overpass and mangled. The tornado weakened further as it passed southeast of Newcastle, with mainly tree and power pole damage noted in that area. Additional minor damage to trees, power lines, and outbuildings occurred as the tornado crossed into Cleveland County, executing a loop in a field before dissipating just west of Moore.

Overall, one person was killed and 48 other people were injured by this tornado along its long path. This tornado followed a similar path to that of a tornado in May 1999.

During the evening of May 24th, this narrow but violent EF4 tornado caused major damage in rural parts of Grady and McClain Counties at the same time another violent tornado from a separate supercell storm was devastating areas in and around Chickasha and Blanchard.
The tornado touched down west of Bradley, causing EF0 to EF1 tree damage as it crossed State Highway 19 (SH-19). Continuing to the northeast, the tornado intensified further to EF3 strength as it passed through rural areas of Grady County, snapping and debarking numerous trees. An extensive swath of ground scouring began as the tornado crossed into McClain County. The tornado then reached EF4 strength as it crossed SH-76, leveling and sweeping away several well-built homes. Vehicles were thrown long distances and mangled almost beyond recognition nearby. The tornado weakened and narrowed as it crossed CR 410, with EF2 to EF3-strength damage occurring in that area. The tornado re-intensified to EF4 strength further to the northeast as it passed between Dibble and Washington. Numerous well-built homes were leveled in that area, and some were swept completely away. Unusual cycloidal debris impact scars were noted in open fields as well. One well-built home in this area with numerous anchor bolts was reduced to a bare slab, though a metal fence immediately next to the house remained standing and grass on the property was not scoured. Another home that was reduced to a bare slab in this area had anchor bolts spaced every two feet (well above the standard of anchoring required for an EF5 rating), though a closer inspection of the home site revealed that a large mobile home frame had smashed into the house during the tornado, and a jacuzzi found in the rubble behind the house was still in usable condition. Due to these contextual discrepancies, damage in this area was rated high-end EF4 rather than EF5. The tornado curved sharply to the north and weakened to EF3 strength as it continued north of Washington, though one final area of EF4 damage occurred southwest of Goldsby as a large, well-built home was completely swept away with only the slab remaining, and large metal storage tanks behind the house were tossed. This home was specifically engineered to be tornado resistant, though close inspection of the foundation revealed that some of the anchor bolt washers were missing, and the ones that were present were slightly too small, preventing a rating higher than EF4. Further to the north, minor EF0 damage occurred near David Jay Perry Airport before the tornado dissipated. Large amounts of debris from this tornado reportedly fell from the sky in Norman.

Overall, the tornado was on the ground for. 61 people were injured, though no fatalities occurred. Despite the presence of multiple well-built, anchor-bolted homes being swept completely away along the path, the tornado was not rated EF5 due to several contextual discrepancies and minor anchoring flaws. A high-end EF4 rating was applied as a result. Despite this, much like the Chickasha–Blanchard tornado, the EF4 rating is disputed, and the tornado is suspected by some to have been an EF5.
During the early morning of May 25th, a very large and violent EF4 wedge tornado tracked through several small communities in western Arkansas.
The tornado touched down at 12:10 AM CDT as an EF1 south of Branch in Franklin County, snapping trees and power poles and damaging a mobile home. The tornado then clipped a section of Logan County, snapping multiple trees before crossing back into Franklin county, where it grew to nearly wide and reached EF4 strength as it tore through the small community of Etna, completely destroying numerous frame homes, mobile homes, and a metal building. Some of the homes were well-built, but were left with only a small amount of debris on their foundations. Several trees were debarked, power poles were snapped, outbuildings were destroyed, and the ground was scarred by debris impacts. One person in Etna was killed, and 6 others were seriously injured. Past Etna, the tornado destroyed a very well-built steel-frame home, leaving only interior walls standing. The structure was not entirely flattened, though an EF4 rating was applied due to how well-constructed the house was. As the tornado crossed back into Logan County, it weakened to EF2 strength but grew extremely large, expanding to in width and snapping numerous trees. The tornado then intensifed to EF3 strength, and once again crossed back into Franklin County, striking the town of Denning. Numerous homes and mobile homes were destroyed in Denning, many trees and power poles were snapped, and large 100-foot tall metal high-tension poles were bent to the ground. Two people were killed in town and 11 others were injured. The tornado then continued into Johnson County and weakened to EF2 strength, heavily damaging several homes in Centerpoint, and downing numerous trees in the community cemetery. The tornado then struck the community of Bethlehem, where frame homes were damaged, mobile homes were destroyed, and one person was killed. Continuing through the Harmony community, the tornado damaged multiple residences, barns, chicken houses, and outbuildings before continuing into the Ozark National Forest and dissipating southeast of Rosetta.

The tornado was on the ground for a total of, killing four people and injuring 27 others.

At least three people were killed in the Atlanta metropolitan area as a result of straight-line winds on the evening of May 26, likely due to a downburst.

Overall, the tornado killed 158 people (with an additional three indirect deaths), injured some 1,150 others, and caused damages amounting to a total of $2.8 billion. It was the deadliest tornado to strike the United States since the 1947 Glazier–Higgins–Woodward tornadoes, and the seventh-deadliest overall.

2011 Joplin tornado

The 2011 Joplin tornado was a catastrophic EF5-rated multiple-vortex tornado that struck Joplin, Missouri, late in the afternoon of Sunday, May 22, 2011. It was part of a larger late-May tornado outbreak and reached a maximum width of nearly during its path through the southern part of the city. This particular tornado was unusual in that it intensified in strength and grew larger in size at a very fast rate. The tornado tracked eastward across the city, and then continued eastward across Interstate 44 into rural portions of Jasper County and Newton County. It was the third tornado to strike Joplin since May 1971.

It also ranks as the costliest single tornado in U.S. history.
Insurance payout was $2.8 billion; the highest in Missouri history, with the previous record of $2 billion being the April 10, 2001 hail storm.

The tornado initially touched down just east of the Missouri-Kansas state line near the end of 32nd Street at 5:34 pm CDT (22:34 UTC) and tracked due east, downing a few trees at EF0 intensity. Eyewitnesses and storm chasers reported multiple vortices rotating around the parent circulation in that area. Civil defense sirens sounded in Joplin 20 minutes before the tornado struck in response to a tornado warning issued by the National Weather Service, but many Joplin residents didn't heed them. The tornado strengthened to EF1 intensity as it continued through rural areas towards Joplin, snapping trees and power poles and damaging outbuildings. Widening, the tornado then tracked into the more densely populated southwest corner of the city near the Twin Hills Country Club. It heavily damaged several homes at a subdivision in this area at EF1 to EF2 strength. The tornado continued to strengthen as it ripped through another subdivision just east of Iron Gates Rd. Numerous homes were destroyed at EF2 to EF3 strength at that location, and multiple vehicles were tossed around, some of which were thrown on or rolled into homes.
The now massive wedge tornado then crossed S. Schifferdecker Ave., producing its first area of EF4 damage as several small but well-built commercial buildings were flattened. Consistent EF4 to EF5 damage was noted east of S Schifferdecker Ave and continued through most of southern Joplin. Numerous homes, businesses, and medical buildings were flattened in this area, with concrete walls collapsed and crushed into the foundations. A large steel-reinforced step and floor structure leading to a completely destroyed medical building was "deflected upward several inches and cracked". Steel trusses from some of the buildings were "rolled up like paper", and deformation/twisting of the main support beams was noted. Multiple vehicles were thrown and mangled or wrapped around trees nearby. Several 300-pound concrete parking stops anchored with rebar were torn from a parking lot in this area and were thrown up to 60 yards away. Iowa State University wind engineer Parka Sarkar was able to calculate the force needed to remove the parking stops and found that winds exceeding 200 mph were needed to tear them from the parking lot.

As the tornado tracked eastward, it maintained EF5 strength as it crossed Main Street between 20th and 26th Streets. It heavily damaged every business along that stretch and several institutional buildings were virtually destroyed. It tracked just south of downtown, narrowly missing it. Entire neighborhoods were leveled in this area with some more homes swept away, and trees were stripped completely of their bark. At some residences, reinforced concrete porches were deformed, or in some cases completely torn away. Damage to driveways was noted at some residences as well. Numerous vehicles were tossed up to several blocks away from the residences where they originated, and a few homeowners never located their vehicles. A large church, Greenbriar Nursing Home, Franklin Technology Center, St. Mary's Catholic Church and School, and Joplin High School were all destroyed along this corridor. The Greenbriar Nursing Home was completely leveled, with 21 fatalities occurring there alone. As the tornado crossed Connecticut Ave further to the east, it destroyed several large apartment buildings, a Dillon's grocery store, and a bank. Only the concrete vault remained at the bank, and a wooden 2x4 was found speared completely through a concrete curb at one location as well. No one was in the high school at the time; the high school graduation ceremonies held about to the north at Missouri Southern State University had concluded shortly before the storm. Pieces of cardboard were found embedded sideways into stucco walls that remained standing at Joplin High School. Steel beams and pieces of fencing were deeply embedded into the ground in fields near the high school as well, steel fence posts were bent to the ground in opposite directions, and a school bus was thrown into a nearby bus garage. The tornado then approached Range Line Road, the main commercial strip in the eastern part of Joplin, affecting additional neighborhoods along 20th Street.

The now heavily rain-wrapped tornado continued at EF5 intensity as it crossed Range Line Road. In that corridor between about 13th and 32nd Streets, the tornado continued producing catastrophic damage as it was at its widest at this point, being nearly wide. As the tornado hit the Pizza Hut at 1901 South Range Line Road, store manager Christopher Lucas herded four employees and 15 customers into a walk-in freezer. With difficulty closing the door, he wrapped a bungee cable holding the door shut around his arm until he was sucked out and killed by the tornado. The tornado completely destroyed Walmart Supercenter No. 59, a Home Depot, and numerous other businesses and restaurants in this area, many of which were flattened. Numerous metal roof trusses were torn from the Home Depot building and were found broken and mangled in nearby fields. Cars that originated at the Home Depot parking lot were found hundreds of yards away. Asphalt was scoured from parking lots at Walmart and a nearby pizza restaurant, and large tractor-trailers were thrown up to 200 yards away. An Academy Sports + Outdoors store along Range Line sustained major structural damage, and a chair was found impaled legs-first through an exterior stucco wall at that location. A nearby three-story apartment complex was also devastated, and two cell phone towers were found collapsed onto the remains of the apartments. Numerous cars were thrown and piled on top of each other, 100-pound manhole covers were removed from roads and thrown, ground scouring occurred, and a Pepsi distribution plant was completely leveled in this area as well. Additional calculations of the manhole covers in Joplin by Parka Sarkar revealed that winds had to have exceeded 200 mph for the manhole covers to be removed. Many fatalities occurred in this area, and damage was rated as EF5.
Extreme damage continued in the area of Duquesne Road in southeast Joplin. Many houses and industrial and commercial buildings were flattened in this area as well. The industrial park near the corner of 20th and Duquesne was especially hard hit with nearly every building flattened. Several large metal warehouse structures were swept cleanly from their foundations, and several heavy industrial vehicles were thrown up to 400 yards away in this area. One of the many warehouses affected was a Cummins warehouse, a concrete block and steel building which was destroyed. The last area of EF5 damage occurred in the industrial park, and a nearby Fastrip gas station and convenience store was completely destroyed. Many homes were destroyed further to the east at EF3 to EF4 strength in a nearby subdivision, and East Middle School sustained major damage.

The tornado then continued on an east to east-southeast trajectory towards Interstate 44 where it weakened; nonetheless, vehicles were blown off the highway and mangled near the U.S. Route 71 (Exit 11) interchange. The damage at and around the interchange was rated EF2 to EF3. The weakening tornado continued to track into the rural areas of southeastern Jasper County and northeastern Newton County where damage was generally minor to moderate, with trees, mobile homes, outbuildings, and frame homes damaged mainly at EF0 to EF1 strength. The tornado lifted east of Diamond at 6:12 pm CDT (23:12 UTC) according to aerial surveys. The tornado's total track length was at least long. Overall, 6,954 homes were destroyed, 359 homes had major damage and 516 had minor damage, 158 people were killed, and 1,150 others were injured along the path. A separate EF2 tornado touched down near Wentworth from the same supercell about east-southeast of Joplin.

A preliminary survey of the tornado damage by the National Weather Service office in Springfield, Missouri, began on May 23. The initial survey confirmed a violent tornado rated as a high-end EF4. Subsequent damage surveys, however, found evidence of more intense damage, and so the tornado was upgraded to an EF5 with estimated winds over, peaking at 225 to 250 mph (360 to 400 km/h).

According to the local branch of the American Red Cross, about 25% of Joplin was destroyed, but the city's emergency manager stated that the number was between 10 and 20%, with roughly 2,000 buildings destroyed. According to the National Weather Service, emergency managers reported damage to 75% of Joplin. In total, nearly 7,000 houses were destroyed (most of which were flattened or blown away) and over 850 others were damaged. Communications were lost in the community and power was knocked out to many areas. With communications down, temporary cell towers had to be constructed. By May 24, three towers owned by AT&T and Sprint had been restored.

Due to the severe damage caused by the tornado, the travelling Piccadilly Circus was unable to perform as scheduled. As a result, the circus employees brought their two adult elephants to help drag damaged automobiles and other heavy debris out of the roadway to make a path for first responders.

East of Joplin, a Risk Management Plan facility released of anhydrous ammonia; it was contained within two days.

The catastrophe and risk modeling firm Eqecat, Inc. has estimated the damage at one billion to three billion USD, but noted that the true damage is not yet known, since the firm does not have access to data on uninsured losses. More than 19,000 insurance claims had been filed by mid-June. The impact on the insurance industry is not so much the number of claims, but the cumulative effect of such a large number of total losses. More than 2500 local people employed in insurance have been involved in some capacity. It is assumed that State Farm will assume the largest share of these losses, having market share of 27% for homeowners insurance and 21% for automobile insurance.

The $2.8 billion in damage is the largest amount for a tornado since 1950.

As of May 2013, the official death toll from National Weather Service was listed at 158 while the City of Joplin listed the death toll at 161 (158 direct). The list was up to 162, until one man's injuries were found to be unrelated to the event. In one indirect fatality, a policeman was struck by lightning and killed while assisting with recovery and cleanup efforts the day after the storm. Shortly after the tornado, authorities had listed 1,300 people as missing, but the number quickly dwindled as they were accounted for. Many people were reported to have been trapped in destroyed houses. Seventeen people were rescued from the rubble the day after the tornado struck.
The Missouri Emergency Management Agency reported more than 990 injured. Of 146 sets of remains recovered from the rubble, 134 victims had been positively identified by June 1. Due to the horrific injuries suffered by some victims, some different sets of remains were from a single person. On June 2 it was announced that four more victims had died.

Six people were killed when St. John's was struck by the tornado. Five of those deaths were patients on ventilators who died after the building lost power and a backup generator did not work. The sixth fatality was a hospital visitor.

The "Joplin Globe" reported that 54 percent of the people died in their residences, 32 percent died in non-residential areas and 14 percent died in vehicles or outdoors. Joplin officials after the tornado announced plans to require hurricane ties or other fasteners between the houses and their foundations (devices add about $600 US to the construction costs). Officials rejected a proposal to require concrete basements in new houses. Officials noted that only 28 percent of Joplin's new homes had basements as of 2009 compared with 38 percent two decades before.

Officials said they rescued 944 pets and reunited 292 with owners.

On June 10, 2011, it was announced that a rare fungal infection, zygomycosis, had been noted to cause at least eight serious cases of wound infection among the injured survivors, confirmed by reports to the Missouri Department of Health and Senior Services.

In 2013, the American Society of Civil Engineers published a study disputing the tornado's initial EF5 rating, based on surveying damage on over 150 structures within a six mile segment of the storm's path. According to the report, over 83 percent of the damage was caused by wind speeds of 135 miles per hour or less, the maximum wind speed of an EF2 tornado. An additional 13 percent was caused by EF3 wind speeds, and 3 percent was consistent with EF4 winds. The study found no damage consistent with wind speeds over 200 miles per hour, the minimum threshold of an EF5 tornado. Researchers concluded that the inability to find EF5 damage was due to the absence of construction standards that were able to determine the necessary wind speeds. Bill Colbourne, a member of the engineering team that surveyed the damage, declared that "a relatively large number of buildings could have survived in Joplin if they had been built to sustain hurricane winds."

However, the EF5 rating stood as the National Weather Service in Springfield, Missouri stated that their survey teams found only a very small area of EF5 structural damage and that it could have easily been missed in the survey (at and around St. John's Medical Center). Bill Davis, head of the NWS station in Springfield, said that the results of the study "do not surprise me at all," adding that "there was only a very small area of EF5 damage in Joplin...we knew right off the bat there was EF4 damage. It took us longer to identify the EF5 damage and that it would take winds of over 200 miles per hour to do that damage." Additionally, the basis for the EF5 rating in Joplin was mainly contextual rather than structural, with non-conventional damage indicators such as removal of concrete parking stops, manhole covers, reinforced concrete porches, driveways, and asphalt were used to arrive at a final rating of EF5, as it was concluded that these specific instances of damage were indicative of winds exceeding 200 miles per hour. The presence of windowed structural debris, instances of very large vehicles such as buses, vans, and semi-trucks being thrown hundreds of yards to several blocks from their points of origin, the fact that some homeowners never located their vehicles, and the overwhelming extent and totality of the destruction in Joplin were also taken into consideration to conclude EF5 intensity.

Immediately following the disaster, emergency responders were deployed within and to the city to undertake search and rescue efforts. Governor Jay Nixon declared a state of emergency for the Joplin area shortly after the tornado hit, and ordered Missouri National Guard troops to the city. By May 23, Missouri Task Force One (consisting of 85 personnel, four dogs, and heavy equipment) arrived and began searching for missing persons. Five heavy rescue teams were also sent to the city a day later. Within two days, numerous agencies arrived to assist residents in the recovery process. The National Guard deployed 191 personnel and placed 2,000 more on standby to be deployed if needed. In addition, the Missouri State Highway Patrol provided 180 troopers to assist the Joplin Police Department and other local agencies with law enforcement, rescue, and recovery efforts which also included the deployment of five ambulance strike teams, and a total of 25 ambulances in the affected area on May 24 as well as well over 75 Marines from the Ft. Leonard Wood Army Base. Within two years the city's workers and community groups compiled and published "Joplin Pays it Forward" to give recovery advice to other places hurt by disaster.

The tornado also highlighted a new form of disaster response, using social media. This type of disaster response is now known as Social Media Emergency Management. News outlets began aggregating images and video from eyewitnesses shared through social media. Public citizen-led Facebook groups and web sites coordinated information, needs, and offers. The results were so effective the project became a finalist in the 2011 Mashable Awards for Best Social Good Cause Campaign.

President Barack Obama toured the community on May 29, flying into Joplin Regional Airport and speaking at a memorial at the Taylor Performing Arts Center at Missouri Southern State University about two miles (3 km) north of the worst of the devastation. Obama had been on a state visit to Europe at the time of the storm. Members of the controversial Westboro Baptist Church were also scheduled to protest the same day in Joplin, but they did not show up. There was a massive counter protest that was organized in response to the Westboro protest, in which thousands of protesters showed up holding signs saying, "God Loves Joplin" and "We Support You Joplin."

Engineers have criticized the tilt up construction of the Home Depot in which all but two of its walls collapsed in a domino effect after the tornado lifted the roof, killing seven people in the front of the store (although 28 people in the back of the store survived when those walls collapsed outwards). Home Depot officials said they disagreed with the study published by "The Kansas City Star" and said they would use the tilt up practice when they rebuild the Joplin store. On June 1, The Home Depot said it would have a new temporary building built and operational within two weeks. In the meantime, it opened for business in the parking lot of its demolished building. On June 20, The Home Depot opened a temporary building constructed by the company's disaster recovery team.

In May 2012, the Missouri National Guard released documents showing that four soldiers looted video game equipment and a digital camera from a ruined Walmart during cleanup efforts. According to the investigative memo, they believed the merchandise was going to be destroyed. All the soldiers were demoted and had a letter of reprimand placed in their personnel file, but were never prosecuted, even though many civilian looters were prosecuted.

Along with the Tri-State Tornado and the 1896 St. Louis–East St. Louis tornado, it ranks as one of Missouri's and America's deadliest tornadoes and is also the costliest single tornado in U.S. history ($2.8 billion). It was the first F5/EF5 tornado in Missouri since May 20, 1957, when an F5 destroyed several suburbs of Kansas City. It was only the second F5/EF5 tornado in Missouri history dating back to 1950. It was the deadliest U.S. tornado since the April 9, 1947 tornado in Woodward, Oklahoma, the seventh-deadliest in U.S. history. It was also the first single tornado since the June 8, 1953 F5 tornado in Flint, Michigan, to have 100 or more associated fatalities.