Tornadoes are deadly and destructive wind storms produced by severe thunderstorms. They can cause extensive damage to buildings and vegetation. A tornado typically consists of a funnel-shaped cloud that reaches the ground. Winds associated with a tornado can exceed 200 mph (322 kph). Damage paths can be greater than one mile (1.6 km) wide and 50 miles (80 km) long.

Tornadoes may appear as a funnel in varying widths. Some contain multiple vortices. Tornadoes can be 'rain-wrapped' and hard to identify. Swirling dust/debris are typical indicators that a tornado has reached the ground.

Weather terms associated with tornadoes are as follows:

  • Tornado Watch: Weather conditions are conducive for tornadoes to develop in or near the watch area.
  • Tornado Warning: A tornado has been sighted on the ground or indicated by radar signature in the warning area.


What to do if Tornadoes Threaten Your Area

Tornado Watch Issued
  • Once a watch has been issued, monitor NOAA weather radio or local media for updated weather information.
  • Find a place to seek shelter, such as a basement or storm cellar. If underground shelter is not available, identify an interior room or hallway on the lowest floor. Be prepared to take shelter quickly.
  • Watch for tornado danger signs: a dark greenish sky, large hailstones, a low-lying rotating cloud, and a loud roar (similar to a freight train sound)


Tornado Warning Issued

When a tornado warning has been issued, you may have very little time to prepare.

If located in a frame house:

  • Seek shelter in the lowest level of the house, preferably the basement. If there is no basement, go to an inner hallway, an interior room, or a closet. Keep away from all windows.
  • Protect your head and eyes from flying debris with a jacket or blanket.
  • Remain in the shelter until the storm has passed; multiple tornadoes can be produced from the same storm.


If located in a mobile home:

  • Leave the structure immediately, and seek shelter elsewhere.


If located outdoors:

  • Seek shelter inside. Avoid large-span roofed buildings such as school gyms, arenas, or shopping malls.
  • If unable to find a building or driving, lie flat on the ground in a low-lying area or ditch. Cover your neck/head with your arms.
  • Avoid seeking cover under highway underpasses; these areas see enhanced wind speeds during tornadoes.
  • Do not attempt to outrun a tornado.


Enhanced Fujita Scale

Tornadoes are ranked on the Enhanced Fujita Scale according to wind speed and damage created.

Enhanced Fujita Scale Wind Speed Damage
EF0 65-85 mph
(105-137 kph)
Some minor roof damage. Tree branches broken off and shallow-rooted trees uprooted.
EF1 86-110 mph
(138-177 kph)
Moderate damage to roofing. Mobile homes overturned. Moving autos pushed off roads.
EF2 111-135 mph
(178-217 kph)
Considerable damage to houses. Large trees uprooted. Mobile homes destroyed.
Lightweight objects become airborne.
EF3 136-165 mph
(218-266 kph)
Severe damage to well-constructed buildings. Trains derailed/overturned.
Large vehicles tossed.
EF4 166-200 mph
(267-322 kph)
Houses leveled. Airborne objects become missiles. Vehicles lifted and thrown.
EF5 >200 mph
(>322 kph)
Total building destruction. Strong frame houses leveled. Concrete structures
damaged. Some vehicles thrown approximately 1 mile (1.6 km).



About WorldAware

WorldAware provides intelligence-driven, integrated risk management solutions that enable multinational organizations to operate globally with confidence. WorldAware’s end-to-end tailored solutions, integrated world-class threat intelligence, innovative technology, and response services help organizations mitigate risk and protect their people, assets, and reputations.