Disasters happen, and a tornado is one of the classic ones that can cause damage and death. Will a new computer-driven warning system give citizens more time to get out of the way of the path of destruction?
A tornado’s a violently rotating column of air in contact with both the surface of the earth and the thunderstorm (sometimes called a “supercell”) that spawned it. Although they’re difficult to see close up, from a distance, tornadoes usually appear in the form of a visible dark funnel with all sorts of flying debris in and around it.
A tornado (also called a “twister”) may have winds of up to 300 miles per hour, and can travel quite a ways, miles and miles, before petering out. They may be accompanied by hail and will emit a roaring sound that will remind you of a passing train. When I say a passing train, I mean a roaring locomotive passing by 3 inches before your nose. We have personally experienced this at our own home, and we can tell you that it is terrifying even though it only caused minor damage
Tornadoes can come anytime, but most often right about now in the part of the country known as Tornado Alley. That’s a group of tornado-prone areas located between the Rocky Mountains and Appalachian Mountains that experiences more tornadoes than anywhere else in the world. It is not an official weather term; it was primarily a phrase popularized by the media.
Now, the first multi-state tornado outbreak of the spring season is being forecast, with weather experts at the Storm Prediction Center (SPC) in Norman, Oklahoma sounding the alarm by issuing a “moderate risk” outlook. Sounds pretty boring, but a moderate risk designation is the fourth-highest on the organization’s five-point scale. About 4 million people live within the risk area, which encompasses Oklahoma City as well as Wichita, Kansas.
Not uncommonly, the tornadoes that are spawned in this situation will cause a lot of damage, as well as possible injuries and deaths. Making them more predictable is the Storm Prediction Center’s mission. Although it uses computer models to issue the latest warnings with more notice than ever before, it’s not certain if they’ll actually help.
It’s possible that, with 15 minutes’ notice, that the only action might be heading to a (hopefully) underground shelter. With an hour, though, would people hide in a shelter or get in the car and hit the road? If they do, is it safer or will they be caught in the path of the twister? Now, we might be able to give some days’ notice, but will it make a difference?
It’s possible that giving people several days’ notice of a potentially stormy day won’t significantly alter their behavior, unlike those who receive similar hurricane warnings. It’s not certain why that is, but I think that these tornado warnings are for an event that doesn’t yet exist, while a hurricane warning is for a storm that’s there: you can see it on the radar heading in your direction and it carries a sense of urgency.
But ignoring tornado warnings isn’t a good idea. Every year, hundreds of people are killed by tornadoes, but many injuries and deaths could have been avoided with some planning.
Injuries from tornadoes usually come as a result of trauma from the flying debris that is carried along with it. Strong winds can carry large objects and fling them around in a manner that is hard to believe. Indeed, there’s a report that, in 1931, an 83 ton train was lifted and thrown 80 feet from the tracks.
Tornadoes are categorized as level 0-5 by the Enhanced Fujita Scale, which is based on wind speeds and the amount of damage caused:
- F0 Light: Winds 40-72 miles per hour; smaller trees uprooted or branches broken, mild structural damage
- F1 Moderate: winds 73–112 miles per hour; Broken windows, small tree trunks broken, overturned mobile homes, destruction of carports or toolsheds, roof tiles missing
- F2 Considerable: winds 113–157 miles per hour; Mobile homes destroyed, major structural damage to frame homes due to flying debris, some large trees snapped in half or uprooted
- F3 Severe: winds 158–206 miles per hour; Roofs torn from homes, small frame homes destroyed, most trees snapped and uprooted
- F4 Devastating: winds 207–260 miles per hour; Strong-structure buildings damaged or destroyed or lifted from foundations, cars lifted and blown away, even large debris airborne
- F5 Incredible: winds 261–318 miles per hour; Larger buildings lifted from foundations, trees snapped, uprooted and debarked, objects weighing more than a ton become airborne missiles
Although some places may have sirens or other methods to warn you of an approaching twister, it’s important to have a weather radio and plan for your family to weather the storm. Having a plan before a tornado touches down is the most likely way you’ll survive the event. Children should be taught where to find the medical kits and how to use a fire extinguisher. If appropriate, teach everyone how to safely turn off the gas and electricity.
If you’re in the path of a tornado, take shelter immediately unless you live in a mobile home. These are especially vulnerable to damage from the winds. If there is time, get to the nearest building that has a tornado shelter, preferably underground.
If you live in Tornado Alley, consider putting together your own underground shelter. Unlike bunkers and other structures built for long-term use, a tornado shelter only has to provide safety for a short period of time. As such, it doesn’t have to be very large; 8-10 square feet per person is perfectly acceptable. Despite this, be sure to consider ventilation and the comfort or special needs of those using the shelter.
If you don’t have a shelter, find the safest place in the house where family members can gather. Basements, bathrooms, closets or inside rooms without windows are the best options. Windows can easily shatter from impact due to flying debris.
For added protection, get under a heavy object such as a sturdy table. Covering your body with a sleeping bag or mattress will provide an additional shield. Discuss this plan of action with every member of your family often, so that they will know this process by heart.
If you’re in a car and can drive to a shelter, do so. Although you may be hesitant to leave your vehicle, remember that they can be easily tossed around by high winds; you may be safer if there is a culvert or other area lower than the roadway. It is not safe to hide under a bridge or overpass, however, as the winds can easily reach you.
In town, leaving the car to enter a sturdy building may be appropriate. If there is no other shelter, however, staying in your car will protect you from some of the flying debris. Keep your seat beat on, put your head down below the level of the windows, and cover yourself if at all possible.
If you’re out hiking when the tornado hits, get away from heavily wooded areas. Torn branches and other debris become missiles, so an open field or ditch may be safer. Lying down flat in a ditch or other low spot in the ground will give you some protection. Make sure to cover your head if at all possible, even if it’s just with your hands.
Joe Alton, MD