Tornadoes Can Strike Any City and Be More Deadly Than Rural Twisters

Urban tornadoes can be up to 16 times deadlier than rural tornadoes.

ByABC News
June 2, 2011, 3:48 PM

June 2, 2011— -- When many Americans think of tornadoes, they think of Kansas and Oklahoma, not Massachusetts and Minnesota. But tornadoes have touched down in both those states in the past few weeks.

Multiple tornadoes slammed western and central Massachusetts Wednesday night, leaving a path of destruction that destroyed buildings, flipped vehicles and left three people dead. A tornado touched down in Brooklynlast year, causing significant damage in the New York City borough.

"The reality is, any city can be hit by a tornado," Kenneth Blumenfeld, visiting assistant professor in the Department of Geography at the University of Minnesota, told ABC News. "If you have sufficient moisture in the atmosphere, instability, some lifting mechanism and the proper wind patterns as they go up into the atmosphere, you can get a tornado. Those conditions tend to be more common in some areas than others, but the fact is, they can arise just about anywhere."

Blumenfeld has been collecting data on urban tornadoes and the statistics he has gathered point to more damage and higher casualty rates after urban versus rural tornadoes.

"Tornadoes that move into major cities tend to kill with between five to 16 times the frequency of tornadoes in rural areas," he said.

Tornado Survival 101: Tips to Stay Safe During a Tornado

This year is already the deadliest for tornadoes since 1953, with more than 500 deaths from more than 1,000 tornadoes so far, according to the National Oceanic and Atmospheric Administration (NOAA). April also set a record as the deadliest month with 361 tornado-related deaths, according to NOAA's records.

The combination of more tornadoes and urban growth has paired to put more populated areas in the paths of tornadoes.

"Part of the issue is that the urban and human footprint is increasing across the landscape, so many areas of the country where several decades ago you didn't have any buildings there, well now you do," Greg Carbin, warning-coordination meteorologist at the NOAA Storm Prediction Center in Norman, Okla. "So the likelihood that you're going to impact structures and have more significant impact over time increases, even if the underlying trend of tornadoes doesn't increase, our vulnerability may be increasing."

Although building regulations for skyscrapers make them much harder to obliterate than single-family homes, tornado strikes in cities can be particularly dangerous.

"People are mostly killed by debris [in tornadoes], so when you've got a lot of stuff flying around and a lot of people, that's a pretty dangerous interface," Blumenfeld of the University of Minnesota said. "If the debris is heavy enough, it's like a series of wrecking balls that bombard buildings until the tornado passes."

Wind tunnels created by buildings can also increase the danger in an already dangerous situation.

"If you try to be outside and hunker down between buildings, the wind tunnel effects you find between buildings in cities on just a regular windy afternoon are pretty potent anyway," he added. "If you throw in even a 100 mph wind and happen to compress it between buildings, you could get extremely dangerous conditions."

Although the majority of the population will never have a close encounter with a raging tornado, experts say, it is important that everyone be aware of what to do if a tornado touches down in your area.