Imagine you are driving down I-49, and you see a tornado coming towards you. There is an overpass up ahead that looks inviting, but should you shelter there? The answer is a resounding NO!!!
Why Isn’t an Overpass a Good Place to Shelter During a Tornado?
It looks safe, but this is a deception. As the tornado approaches the overpass, the amount of air swirling around the vortex is then forced into a much smaller area. You can’t just get rid of the air, so the same volume of air must travel through a smaller space. This restriction of the airflow lowers the pressure of the air, thereby creating an increase in wind speed. This is what scientists call the Venturi effect.
This means that the already violent winds of the tornado will actually increase in intensity underneath the overpass. This wind can be intense enough that you could actually be blown out of the overpass, resulting in significant injury or even death.
The second reason to NOT seek shelter under the overpass is the debris from the tornado. This debris could contain multiple dangerous items that you would be unsheltered from. Being exposed to the tornadic debris could also result in serious injury or death.
Where Should You Seek Shelter Outside?
The best place to seek shelter outside, believe it or not is in a low lying ditch. Yes, this means you should NOT stay in your vehicle, and should abandon it. A vehicle can easily be tossed and flipped by the tornadic winds. This is because the strong winds can easily get under the vehicle allowing it to become airborne. You definitely don’t want to be in it when that happens!
Being in a ditch, places you on the ground, and keeps the high wind from getting underneath you and lifting you up. The embankments on either side will also protect you somewhat from the debris of the tornado as it passes by.
Obviously the best practice is to stay weather aware, know when tornadoes are possible, and stay in your place of residence until the threat passes.
Keep these tips and advice in mind, and you can stay safe when tornadoes are in the forecast!