Tornadoes have long been the subject of old wives’ tales.
Many of these myths have been debunked over the years — it turns out you don’t have to open your windows so your home won’t explode — but with tornadoes barely skirting both Kansas City and New York City last week, many are asking why tornadoes seem to avoid urban centers.
Some say skyscrapers are the main deterrent that keep tornadoes at bay, but experts say this, too, is a tall tale.
Instead, it’s all just a matter of luck and the relatively small size of cities when compared to expansive rural areas, according to the Storm Prediction Center, which is part of the National Oceanic and Atmospheric Administration.
“The chance of any particular tornado hitting a major downtown is quite low — not for any meteorological reason, but simply because downtowns are small targets,” the website states. “Even when tornadoes hit metro areas their odds of hitting downtown are small out of space considerations alone.”
To the contrary, some experts suggest skyscrapers might actually make bad weather more severe due to the effect of “urban heat islands,” which the Environmental Protection Agency refers to as “built up areas that are hotter than nearby rural areas.”
“In our modeling studies, (the heat) would actually increase the intensity of the storms, not decrease,” meteorologist Dr. Victor Gensini said, according to NPR.
History holds that urban centers are far from immune to tornadic activity. The Storm Prediction Center recognizes 29 “downtown tornadoes” that hit city areas between 1871 and 2013 in places such as Raleigh, St. Louis and Atlanta.
On May 22, Jefferson City, Missouri, was ravaged by a violent storm that destroyed 78 buildings, some near downtown, according to the St. Louis Post Dispatch.
But don’t get too worried: Dr. Gensini says a tornado hitting an urban center such as Chicago is not likely, even though it’s possible, according to NPR.
“These are extremely low probability events,” he said. “They’re very small scale. People think of tornadoes as these big things, but in the atmosphere they’re very, very small. And their paths of damage are often only a couple yards wide.”