Go down and in when the tornado warning comes

The alert goes off, or the siren. The pull is to go to the window and look for it, and then to work out which way to run. Neither helps, and the second can kill you. One discussion began with advice on which direction to run, and the people who answered it — storm spotters, a meteorologist, people who live in tornado country — spent the conversation taking that idea apart.

When a tornado warning comes, go down and in: to the lowest floor, the room with the most walls between you and outside, away from windows, with your head covered.

Why running is the wrong plan

A tornado can move from almost standing still to more than sixty miles an hour, and the US National Severe Storms Laboratory puts a typical one at ten to twenty — faster than you run, and faster than traffic moves on a jammed road. Some people add that it can change direction abruptly, and one describes a single storm that changed its speed, width, direction and strength as it went.

Many people warn about how a tornado looks when it is coming for you. If it does not seem to move left or right, it may be coming straight at you, and from where you stand you cannot tell, so treat it as coming at you. A National Weather Service spotter guide says it in one line — if a tornado does not appear to be moving, you are not safe. Waiting to see which way it goes is the mistake.

The rule people reach for instead — tornadoes travel northeast, so go southwest, or south — is defended by some people as a last resort when there is no shelter, and taken apart by others. One meteorologist says it will get people killed. As one person explains it, the trend holds across hundreds of kilometres and means nothing across the kilometre or two around you: a tiny change in angle moves the path by hundreds of metres on the ground. One person points out that driving south to escape a tornado coming from the southwest can put you straight into its path, and one person points to a tornado in Texas that did not travel northeast at all. Rain can hide the funnel completely, and at night you will not see it, some people add; running blind is how people run into it.

What kills in a tornado, one person says plainly, is less the wind itself than what it carries — cars and pieces of buildings. Some people make the same point about standing upright in the open, and one person adds that flying grit can badly injure your eyes even when nothing large hits you. One person adds that a tornado is not a vacuum sucking things up; it is wind moving sideways at enormous speed. That is why low and inside works. Every wall between you and the outside is something the debris has to get through first, and lying flat in low ground puts you beneath the worst of it.

Where “down and in” is in your home

Below ground is the place. Some people call a basement the closest thing to safe there is, and the CDC says the interior part of a basement is the safest place in a home. Get under something sturdy — a heavy table or a workbench — or pull a mattress or sleeping bag over you, the Storm Prediction Center says; some people recommend heavy blankets and mattresses too. And check what is above you: the CDC and one person both warn against sheltering under heavy things on the floor above — a fridge, a piano, a waterbed — which can come through.

No basement is normal in parts of tornado country. One person points out that in Oklahoma most houses there do not have one, because of the soil, the water table and the building codes, and that a dedicated storm shelter is the better bet; another person says basements are not standard in parts of Alabama either, which makes a neighbour’s shelter worth knowing about now, not during the warning. Without one, the Storm Prediction Center’s order is the lowest floor, then a small room in the middle of the building — a bathroom or closet — or under the stairs, or an inside hallway with no windows. Some people say a bathtub in that room is worth getting into. One person points out a detail: it calls the idea that the plumbing protects you bad advice; what a small room gives you is its walls. One person warns that a basement or shelter can flood if pipes burst or water rises, so know your way out.

A mobile home is the one home you leave. The Storm Prediction Center’s advice is blunt — get out, even if it is tied down — and go to a shelter or a nearby sturdy building using a plan you made in advance; the CDC says mobile homes can turn over in strong winds; if there is no shelter nearby, it says, lie flat in the nearest ditch, ravine or culvert and shield your head with your hands. Some people warn leave it, and one of them adds the ditch. The plan is the part to make today: where you will go, and how long it takes to get there.

At work or school, the National Weather Service says follow your drill and go to the shelter area calmly, away from windows and away from big open rooms like cafeterias, gyms and auditoriums.

Put shoes on before you go to the room, some people say, because after a tornado the ground is glass and splinters — even at night, one person adds. One person’s addition is a helmet, a bike or sports one. The CDC says head injuries are a common cause of death in tornadoes, that it has no research on whether helmets help, and that a helmet is never a replacement for shelter; if you use one, keep it where you can grab it. And keep a flashlight and a battery radio in that room, some people say. One person’s advice is to register a storm shelter with the local authorities so rescuers know to look there; it is worth asking your city or fire department whether they keep a list.

If you are in a car, or outside

Here the current US guidance is worded differently from one agency to the next, so here is each one.

The National Weather Service: a vehicle is not a safe place in a tornado. The best thing is to drive to the closest shelter. If you cannot get to one, either get down in the car and cover your head, or leave the car for low-lying ground such as a ditch or ravine. The CDC gives the same first step: do not try to outrun it, drive to the closest shelter. The federal preparedness site and the Storm Prediction Center add the one case for driving away: if the tornado is visible, far away, and the traffic is light, you may be able to drive out of its path by going at right angles to it. If extreme winds or flying debris catch you, they say, park as quickly and safely as you can, out of the traffic lanes, stay in the car with your seat belt on and your head down below the windows, covering it with your hands and a coat or blanket — and leave the car to lie down only if you can safely get noticeably lower than the road. The Storm Prediction Center also says, plainly, that there is no safe option in a car, only less dangerous ones.

People split along exactly that line — three say get out and lie in a ditch because cars are thrown, two say drive away at right angles unless you are stuck in traffic — and their own decider matches the guidance: how far away it is, and how clear the road is. So the judgement is yours, and it runs like this. With a shelter you can reach, drive there. With the tornado far off, in sight, and an empty road, going at right angles to its path can take you out of it. If you cannot reach a shelter and you are in traffic, or the tornado is close, or you cannot see it in rain or darkness, stop driving. Park out of the traffic lanes, and then choose between the two the guidance allows: stay buckled with your head below the windows, or get out to ground clearly lower than the road and lie flat with your head covered. Some people add that an airbag will not protect you from a tornado. One person warns that highways clog with traffic when a tornado comes, and another says do not set off for a relative’s house when the sirens sound: stay where you are and take shelter.

Never under a bridge or overpass. Many people warn against it, and some explain why: the gap under a bridge squeezes the wind so it blows harder, debris is funnelled through, and you are higher up, not lower. The Storm Prediction Center agrees — bridges can make the wind faster, debris still gets in, people can be blown out, the bridge itself can fail, and cars parked there block the road for everyone else. One person adds that a parked car under an overpass can be lifted by wind getting underneath it. One person argued that a big concrete bridge must be safer than a ditch; the correction, citing the weather service, is that the wind speeds up through the opening.

Caught outside on foot, get into a ditch or any dip in the ground and lie flat, some people say, and the CDC gives the same advice. Being upright is what exposes you to the debris. To the question of whether a tornado would just pick you out of a ditch, the answer here is that lying flat lets the wind pass over you rather than get underneath you. Some people warn that a ditch can flood fast in a storm, and one says do not lie under power lines.

Who this page is not for

If you live or work in a high-rise, this page doesn’t cover it, but the Storm Prediction Center’s advice for an office building, hospital or skyscraper is to go to an enclosed, windowless area in the centre of the building, on the lowest floor you can, then crouch down and cover your head; interior stairwells are usually good places, and stay off the elevators, which can trap you if the power goes. If you or someone you care for cannot get to a lower floor quickly, this page does not have your answer, and your local emergency management office is the place to ask what your building’s plan is. If you are thinking of chasing a storm, every caution here that mentions it has one message for you: leave that to trained professionals. And if you live somewhere tornadoes do not happen, some people point out that the tips about sirens and warnings do not apply to you.

Pick the room today, and when the warning comes it is a walk, not a decision.