Tornados in cities

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Why is it that it seems like tornados never hit major cities (even in south and Midwest) seems like it’s always small towns. Even if they do spawn in major cities they seem to avoid any major areas. I Don’t seem to hear of massive cities getting leveled by tornados. (Atleast in my area)

In: Planetary Science

8 Answers

Anonymous 0 Comments

The heat Island effect caused by roads, parking lots, and large buildings somewhat protects cities from tornadoes and similar storm types. They can still hit them, but the pressure differences between the city air temp and the surrounding area air temps typically deflect them.

Anonymous 0 Comments

It happens, but a tornado isn’t going to “level a massive city”, they’re not *that* large, but they still will carve a rather destructive path through one.

Better warning has prevented loss of life.

https://en.m.wikipedia.org/wiki/List_of_tornadoes_striking_downtown_areas_of_large_cities

Anonymous 0 Comments

OKC gets hit [fairly regularly](https://www.weather.gov/oun/tornadodata-okc).

Downtown Atlanta was hit pretty hard [in 2008](https://en.m.wikipedia.org/wiki/2008_Atlanta_tornado_outbreak).

Nashville had a bad one [in 2020](https://www.wunderground.com/cat6/at-least-22-killed-by-overnight-tornadoes-in-middle-tennessee)

But most tornadoes don’t hit major cities because 1) there aren’t many major cities in the areas of the country most prone to tornadoes and 2) major cities are a very small percentage of land area compared to rural areas, which means even if tornadoes were evenly distributed across the country, a majority of them would still miss major cities just based on percentages.

Anonymous 0 Comments

As an illustrative exercise: calculate the area of a major city, then calculate the area of land likely to be hit by a tornado and compare. Even at 1% it would mean that only 1 out of every 100 tornadoes would hit it (if tornadoes were evenly distributed across said land area).

I live in Indiana. The area of our largest city (Indianapolis) is [380 square miles](https://en.m.wikipedia.org/wiki/Indianapolis) or so. The area of the entire state is 35,817 square miles.

Indianapolis represents 1.033% of the land area of the entire state.

Indiana gets something like [25 tornadoes per year on average.](https://wishtv.com/weather/weather-stories/ohio-river-valley-has-been-a-hot-spot-for-tornadoes-so-far-in-2024/)

Based on that, you’d expect a tornado to affect Indianapolis about once every 4 years.

According to this https://www.weather.gov/ind/marion_torn, Marion county (the county where Indianapolis is) has experienced 47 tornadoes since 1950.

Which works out to about one every year and a half.

So to answer your question: cities do get tornadoes, it’s just rare enough that it doesn’t feel like it. And if when you say “cities” you’re picturing a downtown with skyscrapers… that actual land area is even smaller. In Indianapolis’s case you’re talking going down from 380 square miles to something like 6-7 square miles at best, which would be two orders of magnitude smaller of a target for tornadoes, or something like a 1 in 10,000 chance of it happening.

Anonymous 0 Comments

Tornadoes are incredibly violent and destructive… but they are also incredibly localized. The average tornado is about 300 feet in diameter – but you don’t want to be directly NEXT to a tornado either, so we’ll call it 500 feet wide of destructive range. It travels 30 miles per hour for about 10 minutes. That means each tornado has a total impact of about 5 miles by 0.1 miles, or 0.5 square miles.

The state of Kansas gets about 100 tornadoes per year. Kansas has an area of about 80,000 square miles. 50 square miles of it gets hit by tornado per year. That means the odds of any given point getting hit by a tornado in a given year are roughly 0.06%. The largest city in Kansas, Wichita is about 160 square miles, so the odds of some part of it getting hit are roughly 0.2% per year if all other things are equal (and other comments have gone into why they are not).

They don’t hit big cities very often in large part because they don’t hit *anything* very often. It’s just that when they do, they do a ton of damage.

Anonymous 0 Comments

Despite how destructive they are, tornadoes are really small and don’t last very long. They’re less (often *way* less) than a mile wide, run by in a couple of minutes, then they’re gone. For comparison, a hurricane is like 300 miles wide and inches along for days at a time. Now, a violent storm that’s a couple dozen yards wide feels huge if it’s on top of you, but it is very tiny compared to the continental United States. It can honestly be very tiny even compared to a city block. A tornado could reduce your next door neighbor’s house to rubble without your house losing a shingle.

Cities are also very small compared to the continental United States (or a tornado alley state, or even most counties in tornado alley, which is how warnings usually come through). Not as small as tornadoes, but small enough that they don’t necessarily run into each other very often just by sheer statistics. Though it does happen. To my knowledge, a tornado has touched down within Chicago city limits twice in my lifetime. A tornado did damage to a building in Salt Lake City once too. But tornadoes just aren’t big enough to hit any specific location often, or destroy a big city in any spectacular way in the few minutes it’s on the ground (and most tornadoes aren’t the strongest “town leveling” ones anyway. The towns that get totally wrecked are simultaneously very small and very unlucky).

I’ve also heard that the density of large buildings may make it hard for tornadoes to form then stay around in big cities for wind reasons, but that may fully or partially be a myth.

Anonymous 0 Comments

People have already correctly answered the question, but it does sonetimes happen. St Louis was hit hard in 1896.
https://en.m.wikipedia.org/wiki/1896_St._Louis%E2%80%93East_St._Louis_tornado

Anonymous 0 Comments

There are a lot more small towns than there are big cities. Throw a dart randomly, you’re gonna miss the bullseye most of the time.