How to prepare for and survive a tornado.
Tornadoes are one of nature's most violent storms. Spawned from powerful thunderstorms, tornadoes can uproot trees, destroy buildings, and turn harmless objects into deadly missiles. They can devastate a neighborhood in seconds. A tornado appears as a rotating, funnel-shaped cloud that extends to the ground with whirling winds that can reach 300 mph (482 kph). Damage paths can be greater than one mile (1.6 km) wide and 50 miles (80 km) long.
Tornadoes may appear in a funnel shape or in a slender rope-like form. Some have a churning, smoky look, and others contain multiple vortices - small, individual tornadoes rotating around a common center. Still, others may be nearly invisible, with swirling dust or debris at ground level as the only indication of the tornado's presence.
Weather terms associated with tornadoes are:
- Tornado Watch: Weather conditions are conducive to the development of tornadoes in and near the watch area.
- Tornado Warning: A tornado has been sighted or indicated on radar and is occurring or imminent in the warning area.
WHAT TO DO IF TORNADOES THREATEN YOUR AREA
Tornado Watch Issued
- Once a watch has been issued, observe the local sky conditions for thunderstorm and tornado activity, and monitor local media for updated weather information. Report any funnel-shaped clouds to your local police.
- 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, often greenish sky, large hail, a large, low-lying cloud, especially if it is rotating, and a loud roar (similar to a freight train).
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, a small interior room, or a closet. Keep away from all windows.
- Cushion yourself with a mattress, but do not use one to cover yourself. Cover your head and eyes with a blanket or jacket to protect yourself against flying debris.
- Do not leave shelter until officials issue the all-clear signal; multiple tornadoes can emerge from the same storm.
If located in a mobile home:
- Leave your home immediately and take 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, crouch for protection beside a strong structure, or lie flat in a ditch or low-lying area. Cover your head and neck with your arms or clothing.
- Avoid driving during dangerous weather that may spur tornadoes. If this is not possible, stay calm and assess the situation.
- If no indoor shelter exists, leave the car, and lie flat in a ditch or other low-lying area deep enough to provide some protection from the storm's wind.
- Do not attempt to outrun the tornado.
Tornadoes are ranked on the Fujita Scale according to windspeed and damage created.
|F0 - Gale Tornado||40-72 mph |
|Some damage to chimneys inflicted. Tree branches broken off and shallow-rooted trees uprooted.|
|F1 - Moderate Tornado||73-112 mph |
|Peels surface off roofs. Mobile homes overturned. Moving autos pushed off roads. |
|F2 - Significant Tornado||113-157 mph |
|Considerable damage caused. Roofs torn off frame houses. Large trees snapped or uprooted. Lightweight objects become missiles. |
|F3 - Severe Tornado||158-206 mph |
|Severe damage results. Roofs and some walls torn off well-constructed homes. Trains overturned. Most trees in forests uprooted. Heavy cars lifted off the ground. |
|F4 - Devastating Tornado||207-260 mph |
|Well-constructed houses leveled. Structures with weak foundations blown off some distance. Cars thrown and large missiles generated. |
|F5 - Incredible Tornado||261-318 mph |
|Strong frame houses lifted off foundations and disintegrated. Automobile-sized missiles fly through the air in excess of 100 mph. Trees debarked. |
- Related Advice:
How to prepare for a hurricane/tropical cyclone/typhoon.
- Related Advice:
How to prepare for thunderstorms and to cope with them safely.