It's A Common Myth That Tornadoes Avoid Cities - But It's Not True

As a former NASA scientist and current professor at a major university, one of my primary research areas has been how urban environments interact with weather and climate processes. One of the things that I have feared throughout my career is the prospect of tornadoes ravaging densely populated cities. In March 2018, a tornado came very close to the world's busiest airport in Atlanta. A mid-April storm, a classic mid-latitude cyclone, brought snow to the upper midwest and tornadic storms to parts of the Southeast. The National Weather Service confirmed that a tornado with 135 mph winds went through the city of Greensboro, North Carolina on Sunday April 15th.  This means a strong EF-2 tornado moved through North Carolina's third most populous city.

In my 25 or so years studying weather, I periodically hear the myth that tornadoes "avoid" or cannot hit a major city. That is simply not true.

Urban areas in the United States

U.S. Census

This myth likely emerged from the fact that tornadoes in major urban areas are relatively rare. Heck, tornadoes themselves are rare in themselves over the course of a given year, but their impact is potentially devastating so they get our attention. The reason they rarely hit a major city is that in the grand scheme of things, urban spaces are relatively small. Roughly 3% of the world's land surface is urban. The graphic above shows the relative amount of urban land cover in the United States. For illustrative purposes, imagine it was a dartboard. If you are an unskilled dart thrower, how often would you hit a city with a dart in 10 throws? Statistically, you are more likely not too.

The map below illustrates where tornadoes are most likely to happen in the United States. It is clear that the traditional "tornado alley" of the Great Plains and the Gulf Coastal Southern states (some have called this "Dixie alley") are the most likely regions. If you juxtapose these two maps, it should be even clearer why tornadoes rarely "hit" a major city. An "unofficial" list of cities hit by tornadoes over the past 100 or so years can be found at this link. NOAA's Storm Prediction Center also maintained a list until 2011 or so.

U.S. tornado watch frequency


Weather Underground is an outstanding resource for all things weather. They published a list of several myths about tornadoes. Here is what the website says about tornadoes and cities,


About a decade ago, Dr. Josh Wurman and colleagues published a paper in the Bulletin of the American Meteorological Society called "Low-Level Winds in Tornadoes and Potential Catastrophic Tornado Impacts in Urban Areas." They used wind estimates from Doppler on Wheels mobile radars, census data, and modeling to estimate impacts of tornadoes crossing densely populated cities. Results were startling. For example, they argued that a large, intense tornado moving through parts of Chicago, Illinois could destroy nearly a quarter of a million homes and result in 4500 to 45,000 deaths. They did similar evaluations for Atlanta, Washington, D.C., Houston, Dallas-Ft. Worth, New York, and St. Louis. While this results may be exaggerated as noted by some scholars in the literature, I think the point that they convey is real.

A 2017 scholarly study presented at the American Geophysical Union meeting also considered urban risks from tornadoes. The scientists fit sophisticated models to casualties from tornadoes since 1995. They found that cities in the Mid South are more likely to experience casualties from tornadoes. This is consistent with findings of researchers at Northern Illinois University nearly a decade prior. 

I want to close with a few points. Urban spaces are continuing to grow. This means that in my dartboard analogy earlier, the city targets are expanding so this may increase the likelihood of what we just saw in Greensboro, North Carolina.  There is a very interesting discussion in Weatherwise Magazine on this expanding bullseye effect with cities. However, I also want to emphasize that even though there are unique threats to urban dwellers facing tornado threats, our warning capacity and attention should not be urban biased. How many times do you see a news station break into programming as a tornado threatens a city? This should be done. However, the urgency should be no less when our fellow citizens in rural communities are threatened too.

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