By Richard P. Holm M.D.
Did you know that three out of four tornadoes in the world happen in the U.S. and that many of them occur in this neck of the woods? Most frequent experiences occur in tornado alley starting early in Texas, and progressively later in the season through the spring and summer up through Oklahoma, Missouri, Kansas, Nebraska, and the Dakotas. That said, tornadoes can happen almost anywhere and at almost any time of the year.
A tornado typically forms when a cold front with wind going one way bumps up against warm moist air going the other way. The theory is that updrafts on one side, and falling rain on the other can start these opposing winds spinning. When one end of the twisting wind is sucked into the updraft of a tall thundercloud, the speed of the whirling is enhanced and becomes concentrated as it tightens down into a funnel, much like a skater spins faster as the arms and legs come in.
About two percent of tornadoes reach speeds of up to 300 mph causing 70 percent of the damage, and 70 percent are minimally destructive, with winds of less than 110 mph.
The major rule to protect oneself from tornadoes is to avoid flying debris. Experts advise avoiding windows, (and not wasting time opening them.) If you are in a sturdy permanent home, go to a lower central windowless room, maybe under a stairwell, or climb into a bathtub. Get low and cover with a mattress or sleeping bag if possible. If in a mall or church, avoid large spaces; find a hallway, bathroom, or smaller windowless room and crouch.
If you are in a mobile home or a vehicle of any kind, get out, as these are all extremely dangerous in a tornado. In a vehicle, if you can safely drive away, do so. Otherwise get off the road, get out and away from anything that can roll over or fall on you. If you cannot find a permanent sturdy building, you are safer in a lower spot or ditch away from cars or trees. Lie flat or crouch; face down, with your arms covering your head. Avoid bridges as they offer little protection against flying debris.
It is wise to make a plan and be prepared since we live in tornado alley.
Dr. Rick Holm wrote this Prairie Doc Perspective for “On Call®,” a weekly program where medical professionals discuss health concerns for the general public. “On Call®” is produced by the Healing Words Foundation in association with the South Dakota State University Journalism Department. “On Call®” airs Thursdays on South Dakota Public Broadcasting-Television at 7 p.m. Central, 6 p.m. Mountain. Visit us at OnCallTelevision.com.