Spring Tornado Season Is Peak Time to Get the Facts Right
Tornado season is underway across much of the United States, and with it comes a fresh circulation of dangerous misinformation about how tornadoes behave and what to do when one threatens. Some tornado myths are merely inaccurate. Others lead people to make decisions that get them killed — choosing the wrong shelter, staying in the wrong place, or delaying action based on a false belief about what they’re seeing or hearing.
The National Weather Service estimates that many tornado fatalities each year are preventable. Understanding what’s actually true about tornado behavior — and letting go of what isn’t — is one of the most direct ways to improve your odds in a tornado emergency.
Myth: Tornadoes Don’t Cross Rivers, Hills, or Valleys
This is one of the most geographically persistent tornado myths, and it takes different forms in different regions. In hilly areas, people believe tornadoes follow valleys and avoid ridgelines, or vice versa. Near rivers, people believe the water creates a barrier. In cities, people sometimes believe tall buildings deflect tornadoes around urban cores.
None of these are true. Tornadoes cross rivers, climb hills, descend into valleys, and have struck the centers of major cities including Oklahoma City, Nashville, Atlanta, and St. Louis. Terrain features can influence a tornado’s path in minor ways — a significant ridge might cause slight deflection in a weak tornado — but no terrain feature reliably stops or redirects a strong tornado. A belief that your town is protected by geography is a belief with no meteorological basis and real potential to cause fatal complacency.
Myth: You Should Open Windows Before a Tornado to Equalize Pressure
This myth has been circulating since at least the mid-20th century and remains surprisingly widespread. The idea is that the low pressure inside a tornado will cause your house to “explode” unless you equalize pressure by opening windows. Opening windows is therefore supposed to protect the structure.
It is completely false, and following this advice costs precious seconds that should be spent reaching shelter.
Houses do not explode from pressure differentials during tornadoes. The damage is caused overwhelmingly by the wind itself — debris striking the structure, and wind forces acting on walls and roof. Any pressure equalization that occurs happens naturally and instantly through the gaps already present in any normal building. Opening windows accomplishes nothing protective and exposes you to the tornado while you’re standing near a wall of glass during a tornado. The time it takes to open windows is time not spent in your safest shelter location.
When a tornado warning is issued, go immediately to your shelter. Do not open windows.
Myth: A Highway Overpass Is a Safe Place to Shelter from a Tornado
This myth was significantly reinforced by a 1991 video that circulated widely on early television and later the internet, showing a film crew surviving under a highway overpass as a tornado passed nearby. The video appeared to show the overpass providing protection. It did not — it showed a near miss in which the tornado’s most destructive winds happened not to pass through that specific location.
Highway overpasses are among the worst possible tornado shelters. The structural geometry of an overpass — a concrete beam creating a narrow channel — actually accelerates wind speed beneath it through a wind tunnel effect. Debris is funneled and concentrated under the overpass rather than passing over it. The girders and beams provide handholds but no actual protection from either wind or debris.
People who shelter under overpasses often climb up toward the beam-girder junction, positioning themselves higher off the ground and more exposed to wind acceleration. Multiple fatalities have occurred under overpasses during tornadoes in the years since the 1991 video, and the National Weather Service has explicitly identified overpass sheltering as dangerous in its tornado safety guidance.
If you are caught in a vehicle when a tornado is imminent and cannot reach a sturdy building, the correct action is to either drive at right angles to the tornado’s path to get out of its way, or — if the tornado is too close — abandon the vehicle and lie flat in a low ditch away from the vehicle, covering your head. Neither option is good. The overpass is worse than both.
Myth: Tornadoes Always Sound Like a Freight Train
The freight train description of tornado sound is the most commonly repeated sensory description of tornadoes in popular culture, and it does reflect what many survivors report hearing. But it is not universal, and treating it as a reliable warning signal can cause dangerous delay.
Tornado sound varies significantly depending on the tornado’s intensity, its distance, the surrounding terrain, and the direction it’s traveling relative to the observer. Some tornadoes — particularly those rain-wrapped or embedded in the broader storm circulation — approach with little or no audible warning. Some produce roaring sounds more like waterfalls or jet engines than freight trains. Some survivors report no distinctive sound at all before impact.
More critically, if you can hear a tornado, it is already extremely close. Sound is not an early warning system — it’s a last-second indicator that a tornado is upon you. By the time you hear it, you should already be in shelter based on a tornado warning, not searching for the sound as confirmation that it’s real.
Rely on official tornado warnings from the National Weather Service, delivered through weather radio, emergency alerts on your phone, and outdoor warning sirens — not on hearing a tornado before seeking shelter.
Myth: Tornadoes Only Happen in Tornado Alley
Tornado Alley — the region of the central Great Plains including Kansas, Oklahoma, Texas, Nebraska, and South Dakota — does have the highest frequency of tornadoes in the world. But tornadoes occur in all 50 states, in every month of the year, and in every type of terrain.
The Southeast has its own significant tornado risk, particularly in the fall and early spring, and its tornadoes are disproportionately deadly because they occur more often at night, in more heavily forested terrain that obscures visual warning, and in communities with higher concentrations of mobile homes. Mississippi, Alabama, Tennessee, and Arkansas have all experienced catastrophic tornado outbreaks that rival anything in Tornado Alley in terms of casualties.
The Northeast, the Pacific Northwest, and even parts of New England experience tornadoes. Florida averages more tornadoes per square mile than any other state, though they are typically weaker. The risk is not uniformly distributed, but no region is tornado-free, and assuming your location is outside the risk zone is a dangerous assumption.
Myth: If the Sky Is Green, a Tornado Is Definitely Coming
As covered in a recent Weather Daily piece on the optics of storm sky colors, a green sky is a real phenomenon associated with severe thunderstorms — but it indicates storm type and intensity, not an imminent tornado. Many severe thunderstorms produce green skies and no tornado. Many tornadoes occur without a green sky, particularly those that strike at night, in winter, or in cloudy conditions that prevent the optical effect from being visible.
The green sky is a signal to pay attention and check your weather alerts. It is not a tornado warning. Conversely, the absence of a green sky is not reassurance — tornadoes can and do form from storms that don’t produce unusual sky colors, particularly at night.
What Actually Protects You
The protective actions that tornado safety research consistently supports are straightforward. When a tornado warning is issued for your area, go immediately to the lowest floor of a sturdy building and put as many walls between yourself and the outside as possible. Interior rooms — bathrooms, closets, hallways — away from windows are best. Get under something sturdy if possible and protect your head and neck.
If you are in a mobile home or manufactured housing, leave immediately for a sturdier structure. Mobile homes offer almost no protection against tornado-strength winds regardless of whether they are tied down, and tornado fatalities are disproportionately concentrated in this type of housing.
Have a plan before tornado season peaks, practice it so it’s automatic, and rely on official warnings rather than sensory cues for the decision to seek shelter. The myths above have persisted because they feel logical or because a single anecdotal experience seemed to confirm them. The physics of tornadoes doesn’t accommodate exceptions, and spring is the season when getting this right matters most.
