Weather Imagery

It is a myth that tornadoes never hit big cities. Pictured to the left is a tornado that ravaged downtown Miami Florida on May 12th, 1997. The fact is tornadoes have a long history of hitting big cities and when they do, they usually cause a great amount of damage because a lot more debris is generated. Tornadoes can form pretty much anywhere at any time, although they usually form in the Midwest during the afternoon hours within “Tornado Alley”.

It’s a matter of statistics rather than a city’s physical attributes as to why tornadoes don’t hit big cities as often. But to say they never hit big cities simply isn’t true.

The “downtown” part of a big city where the big skyscrapers are situated is usually pretty small in comparison to the city as a whole. As a result, that particular spot has a smaller target and therefore a smaller probability of getting hit by a tornado. But that doesn’t mean downtown areas are immune or somehow repel tornadoes. In fact, a house outside the city with a much smaller footprint has even less of a chance of getting hit just because it is even a smaller target.

In addition, geography also plays a big role in the probability of tornadoes forming and hitting big cities. For the same reasons the Midwest is a favorable location for their formation, other places near the ocean, in the dessert or in the mountains are not. Therefore, big cities outside of tornado alley have an even less probability of being hit by a tornado. But this doesn’t mean they cannot form there. Tornadoes can form just about any place. A tornado was documented above 10,000 feet by a hiker in the Utah Mountains and I remember as a kid hearing about a tornado that formed off the coast of Southern California near Palos Verde.

Here is just a small list of cities that have been hit by tornadoes:

• Dallas, TX
• Miami, FL
• Los Angeles, CA (30 tornadoes since 1918)
• Oahu, HI
• Oklahoma City, OK (F5 Tornado)
• Salt Lake City, UT
• St. Louis, MO (22 tornadoes in the past 40 years)
• Sunnyvale, CA (right smack in the middle of Silicon Valley)
• Witchita Falls, KS

Another reason why large cities never seem to get hit is that there are very few large cities with tall skyscrapers in Tornado Alley. Oklahoma City is hardly “big” by todays standards, but it is pretty much right in the middle of the action. Dallas-Forth Worth as well. St Louis is another city that is in Tornado Alley and it does have a long history of destructive tornadoes. Approximately 22 have hit the city in the past 40 years alone. But after that, the cities in Tornado Alley are much smaller in size and less numerous as compared to the east and west coast. If Los Angeles or New York were located in “Tornado Alley” this myth may have less potency. A vast number of tornadoes that do form are out in the middle of fields and unpopulated areas in the Midwest. So a smaller percentage of them actually hit the big cities, but that doesn’t mean big cities repel them or an immune from them.

One could make the argument that tall skyscrapers could affect the air flow patterns needed to sustain a tornado. But it’s probably unlikely that a few buildings which are a few hundred feet in size would have much of an affect on a supercell which can grow to heights in excess of 50,000 feet (9 miles) and be as big as Mount Everest. Even a tornado itself can be as wide as a mile or more. So as of this writing, no scientific evidence has proven this myth otherwise.

Other Tornado Myths

• Do Mobile Home Attract Tornadoes?
• Does Opening Windows During a Tornado Help?
• Is The Southwest Corner Safest?
• Do Highway Overpasses Provide Safety?
• Can You Really Outrun A Tornado In A Car?