Tornadoes are one of nature’s most violent and unpredictable storms, capable of tremendous destruction and loss of life. Understanding the primary causes of death during a tornado can help people be better prepared when tornado warnings are issued.
The leading cause of death during a tornado is flying debris. When tornado winds reach speeds over 100 mph, they can turn anything not anchored to the ground into deadly projectiles. Pieces of wood, metal, glass, bricks, and other debris can all become high-speed missiles penetrating structures and causing traumatic injury or death.
According to the National Oceanic and Atmospheric Administration (NOAA), flying debris alone accounted for 76% of all tornado fatalities documented in the United States from 2006 to 2019. This highlights how essential it is to shelter in a small, fortified room during a tornado rather than trying to outrun the storm.
Head and Neck Injuries
Due to the random trajectories of windblown debris, head and neck injuries are extremely common in tornado casualties. A 2018 study published in the International Journal of Disaster Medicine analyzed 120 deaths resulting from a devastating tornado in Joplin, Missouri in 2011. It found that nearly half of the fatalities had severe head or neck trauma, predominantly caused by high-velocity debris.
Penetrating trauma from debris is another significant threat during a tornado. Debris traveling at over 100 mph can easily pierce the human body. According to the Joplin tornado study, 22% of the deaths examined were due to penetrating trauma from debris blows to the head, neck, chest, abdomen or extremities. Large, irregular shards of wood and other debris can cause especially severe impalement wounds.
After flying debris, the second greatest cause of tornado fatalities is blunt trauma from strong winds creating powerful shockwaves and debris impacts. According to the NOAA, about 17% of tornado deaths result from blunt trauma. Even without penetrating injuries, the concussive forces of tornado winds can cause severe internal injuries and hemorrhaging.
One of the consequences of extreme blunt trauma is traumatic asphyxiation. This occurs when strong compression forces prevent the lungs from inflating properly. It accounts for approximately 10% of all tornado deaths. Violent blunt trauma to the chest can also cause severe heart contusions that rapidly lead to death.
Blunt force head trauma is another common cause of death in tornadoes. Debris impacts or extremely strong tornado winds can easily fracture the skull. This can cause brain lacerations, intracranial hemorrhaging, and other traumatic brain injuries with a very high mortality rate.
Tornadoes are often spawned by severe thunderstorms and Category: accompanied by heavy rainfall. Flash flooding is responsible for around 4% of tornado deaths in the U.S. Moving at high speeds, floodwaters can wash people or vehicles away. Flood debris and downed power lines in the water also increase the drowning hazard.
Tragically, many flood-related tornado fatalities occur because people underestimate the power of flash floodwaters. Being pulled or washed into a storm drain is one of the gravest flood threats during a tornado. Storm drains create dangerous siphon effects as water rushes through them, sweeping away anyone caught in the flow.
Trying to drive through floodwaters is extremely dangerous, yet many tornado deaths occur this way. According to NOAA statistics, over half of all flash flood fatalities are vehicle-related. Just 18 inches of moving water can sweep away a large SUV. Floodwaters also push debris into roads, damage bridges, and conceal washed out sections.
While flying debris is the main source of penetrating trauma in tornadoes, the enormous wind forces can also crush and collapse structures, killing through crush injuries. According to the NOAA, about 4% of tornado fatalities are due to crush trauma from buildings or trees falling onto victims. Vehicles can also be crushed by falling trees, poles and powerlines.
Those sheltersing in basements, bathrooms and small interior rooms during a tornado are at highest risk for crush injuries. The entire structure may fall in on top of them. However, not sheltering in a secure space also leaves people exposed to flying debris and blunt trauma from tornado winds.
Many crush fatalities also occur when cars, trucks, or buses are picked up and smashed by extreme tornado winds. One study found that around 1 in 5 tornado deaths happen to people riding in vehicles. Being properly restrained and keeping helmets on in vehicles can potentially reduce serious injuries.
Beyond the immediate, physical dangers, tornadoes also kill through indirect causes that account for a smaller number of fatalities:
- Myocardial infarction – 1% – Heart attacks brought on by stress and fear.
- Carbon monoxide poisoning – 1% – From improper use of grills, generators.
- Electrocution – 1% – Downed power lines, lightning strikes.
- Structural fires – 1% – Caused by gas leaks, electrical issues.
While tornadoes can be deadly for anyone caught exposed, some segments of the population are more vulnerable and at risk:
- Elderly – Less able to take quick shelter and more likely to suffer medical emergencies from the stress.
- Young children – Require assistance taking protective actions.
- Disabled – May not be able to properly shelter or evacuate.
- Impoverished – More likely to live in unstable structures.
- Non-native English speakers – May not understand warnings.
Making sure at-risk groups have the resources and support systems in place to stay safe during tornadoes helps prevent unnecessary deaths.
Prevention Through Preparedness
While tornadoes are nearly impossible to predict precisely and avoid, there are prevention measures people can take to protect themselves:
Make sure everyone knows where the safest interior room is in your home or other structures you occupy frequently. This room should have no windows and be in the framing center of the building. Keep helmets and other protective gear there if possible.
Make sure all phones are enabled to receive emergency weather alerts. Have a weather radio that will sound alarms for your area. Know the difference between watches and warnings.
Head to shelter before the tornado arrives – ideally when warnings are first issued. Do not wait until the tornado is visible to take action.
Get out of vehicles and lie flat in a low area. Vehicles are extremely dangerous places to be during a tornado.
Note where potential sources of debris are located near your shelter space. Move dangerous debris inside or secure it against the expected wind direction when possible.
Preparing people to effectively shelter from flying debris, avoid crushing forces, and quickly escape floodwaters offers the best defense against tornado dangers. Public awareness campaigns should focus on the realities of how most tornado casualties actually occur. Empowering residents to be active participants in their own safety is key to making communities more tornado resilient.