Hurricanes only strike certain coastal regions and earthquakes are largely confined to well-identified areas but all 50 states have experienced a tornado at one time or another. Much shorter in duration than a hurricane, a tornado can be just as deadly and cause more destruction.
On May 3, 1999 a deadly series of tornadoes tore through Oklahoma, killing 40 people and causing nearly 700 injuries. An F5 twister stayed on the ground for nearly 90 minutes, cutting a 38-mile path of destruction from Chickasha through southern Oklahoma City.
Because these storms can form quickly and strike with deadly force, knowing the warning signs and what to do when one approaches can be the difference between life and death.
Tornadoes are most likely to form in conditions that spawn severe thunderstorms. Hot, humid weather is often common but so is a clash of temperature extremes, when two fronts collide. When these conditions exist it is wise to keep eyes and ears on weather bulletins.
In addition, your eyes and ears can tell you that conditions are ripe for a tornado. According to the NOAA Storm Prediction Center in Norman, Okla., you might observe strong, persistent rotation in the base of a cloud. You might also see whiling dust or debris on the ground, minutes before a funnel forms.
A forming tornado will often produce hail and heavy rain – and then suddenly, the wind dies down and the sun comes out. You might observe debris, like small tree limbs, actually floating in the air. An approaching storm will many times turn the sky an eerie shade of green.
Tornadoes that strike at night are particularly deadly because so many people are asleep and can't see the approaching storm. But they can often hear it. A tornado is usually accompanied by a loud, continuous roar or rumble.
You may also see small, bright blue-green to white flashes near ground level. That is usually a sign of snapping power lines and the approach of a funnel cloud.
Regardless of the time of day, the Centers for Disease Control and Prevention (CDC) advises anyone in the path of a suspected tornado to take shelter immediately
“The key to surviving a tornado and reducing the risk of injury lies in planning, preparing, and practicing what you and your family will do if a tornado strikes,” the CDC says. “Flying debris causes most deaths and injuries during a tornado. Although there is no completely safe place during a tornado, some locations are much safer than others.”
A basement or shelter below ground will be the safest. In a house with no basement, go to the lowest floor and stay clear of windows. Crouch as low as possible in a small center room, under a stairwell or an interior hallway.
If possible, cover yourself with thick padding, like a mattress. Lying in a bath tub might offer a shell of partial protection.
After the storm
Once a tornado has passed conditions can still be dangerous. If you have suffered damage or injuries, keep family members together and wait for emergency personnel. If you can safely render aid to someone who is injured, do so.
Damage from the storm can pose a serious threat threat long after the tornado has left the area. Stay clear of downed power line since they may still be hot. Watch your step, since broken glass, nails and other sharp objects could be everywhere.
Don't go into heavily damaged buildings since they could collapse at any time. Find a working radio, TV or smartphone and get instruction from local officials and news about the storm.
If you live in the Midwest or Great Plains, two areas at high risk of spring tornadoes, it's a good idea to assemble a disaster preparedness kit for the season. Federal disaster officials provide this list of things that should go in it.