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Tornadoes are known to throw 18 wheelers and other large objects into the air. However, most deaths (to humans) are due to debris rather than being thrown by the wind itself.

There are several claims that twisters have lifted cows into the air:

Several cows and one bull survived being carried more than a quarter mile by a tornado Tuesday evening near Elgin. The cattle were reportedly tossed over fences into an adjacent pasture.

(Perhaps most famously, it was depicted in a CGI scene from the movie Twister (1996).)

From a physics perspective sky-bound cows seem unlikely. The houses and cars that tornadoes play with are very heavy but also hollow and low density. Solid objects are much harder to move. A human terminal velocity is about 120 mph in a belly-down position (maximizing drag) but humans can fall at a speed of up to 310 mph in a streamlined vertical dive. This is faster than the most powerful tornado on record. A cow, which can weigh over a tonne, presumably could fall at a velocity of well above 200mph. Terrified cows may find themselves in odd places, and debris are still highly lethal. But flight?

The poorly-resolved "cow" in the first film could be a piece of siding or other debris. Instead of "being carried over a fence" terrified bovines simply jumped and/or trampled the damaged(?) fence. The article provides no evidence besides "someone said so".

Has there been a well-documented "flying cow"?

Kevin Kostlan
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  • Comments are not for extended discussion; this conversation has been [moved to chat](https://chat.stackexchange.com/rooms/142406/discussion-on-question-by-kevin-kostlan-do-cows-get-blown-through-the-air-by-tor). – tim Jan 28 '23 at 08:37

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I wrote this before I realized this is the same video linked in the question. Rather than deleting it, I think digging into its background and the credibility of the source is worth an answer even if it is not definitive.

Stormchaser and AccuWeather Extreme Meteorologist Reed Timmer, PhD claims to have seen cows flying through the air. His credentials lend this more credibility than other claims.

From Reed Timmer details the heart-pounding moments from 5 of his most extreme storm chases in 2018

Tornado in Federal, Wyoming... May 27 he chased a tornado on a flat tire for about 10 miles. He knew that if he had stopped to fix it, he would have missed the storm completely. The EF2 twister was around 2 to 3 miles in length, according to the National Weather Service. Estimated peak winds were approximately 111-135 mph. “Sadly, it hit some farmhouse there and I saw cows flying through the air,” said Timmer. “That’s the first time that I have seen with my own eyes livestock flying through the air inside a tornado.”

Reed has video of the event on his YouTube channel. At 1:09 he exclaims "Cows! Cows going through the air!". The video is pretty indistinct, you decide.

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Schwern
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    I just realized this is the same video linked in the question. I think digging into its background and the credibility of the source is worth an answer. – Schwern Jan 24 '23 at 07:14
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    Sorry but those are not cows. Clearly the cameraman was caught in the heat of the moment, when he confused that debris for livestock. – NoseKnowsAll Jan 24 '23 at 17:59
  • @NoseKnowsAll Maybe a bit of confirmation bias also. – Wayne Conrad Jan 24 '23 at 20:49
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    @NoseKnowsAll, yeah, I looked at this video full screen on my 49" 4K TV at 1/4 speed, and those aren't cattle. I grew up on a farm with friends and family having cattle, so I know what they look like. The things in the air weren't that. It looks more like sheet metal or maybe a tarp, but not cattle. Even at 1080p, the resolution isn't good enough to see any real detail. The fact that they disappear at times makes me think they are something flat, but sometimes folded into a rough shape of an animal. Also, it horses are roughly the same shape and size as cattle, so positive id is unlikely. – computercarguy Jan 24 '23 at 21:02
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    Stack Exchange encouraged me to leave a comment: I have downvoted this answer because the question asks for a well-documented "flying cow" and this answer is not that. The question literally linked to this video and literally discussed the issues with the video. Please don't take the downvote personally; for what it's worth, your "answer" allowed the question to become a "Hot Network Question", which will increase its reach. – A. Rex Jan 25 '23 at 03:54
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    135mph is around cruise speed of Cessna 172 light aircraft. That plane has *wings* and is in general not shaped like a cow, but weight is in same ballpark. There's *no way* that you make me believe that a cow would fly at 135mph. – vidarlo Jan 25 '23 at 06:26
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    @vidarlo that's not flying. It's falling. With style. 135mph is the ground speed of the wind. We're talking about a tornado. They're also known to produce an updraft. Belly down human skydivers have a terminal velocity of [120 mph](https://en.wikipedia.org/wiki/Speed_skydiving). So you have the speed but you measured it in the wrong direction. My point? I doubt these are cows. But I want it disproved with a better argument. – candied_orange Jan 25 '23 at 13:54
  • Updraft is still wind speed. – vidarlo Jan 25 '23 at 13:56
  • @vidarlo an updraft has a wind speed. Are you claiming it's always the same as ground speed? – candied_orange Jan 25 '23 at 13:57
  • @vidarlo Looks like updrafts have been clocked at [100 mph](https://igppweb.ucsd.edu/~gabi/sio15/lectures/Lecture19.html) to [150 mph](http://www.phys.ufl.edu/~peterson/tornado/micktornado.html) but that isn't proof that this is what happened here. – candied_orange Jan 25 '23 at 14:20
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    One factor is that [cows are more or less spheroids](https://en.wikipedia.org/wiki/Spherical_cow), and that mass increases with cube of the radius, whilst area increases with the square... – vidarlo Jan 25 '23 at 14:26
  • I suggest removing this answer as it doesn't really answer the question – JonathanReez Jan 25 '23 at 20:24
  • @JonathanReez it seems like it does answer "yes", but are you saying it should be removed for being wrong? – Matthias Jan 25 '23 at 21:42
  • @Matthias it's wrong because it references the video OP put into question and doesn't prove that it's indeed a cow – JonathanReez Jan 25 '23 at 21:43
  • @computercarguy You don't need something folded--a vaguely animal shaped flat object (say, sheet metal) will look like an animal when vertical and disappear when horizontal. – Loren Pechtel Jan 25 '23 at 22:28
  • @LorenPechtel, what I didn't mention is that the object in flight looks vaguely like a cow from a top down angle, so looking at the spine of the animal. Not many cutouts are going to look like that. And the spine view is going to be the thinnest a 4 legged animal is likely going to look, so they should get bigger when rotated to nearly any other angle, not disappear. But yes, a cutout of an animal could work for a similar situation. – computercarguy Jan 25 '23 at 22:40
  • @computercarguy I'm just objecting on folded--a flat sheet can produce the effect. – Loren Pechtel Jan 25 '23 at 22:43
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I could not find any reference for cows. But the effects on strong winds in cyclones or tornadoes are well documented on the Fujita and Enhanced Fujita scales and on a less used but tornado targetted scale the Torro(*) scale.

According to my student memories, the effects of a moving fluid on a solid depend on:

  • the weight of the solid (inversely proportional according to the fundamental law for dynamics: F = m gamma)
  • the surface of the solid (proportional: the larger the surface, the larger the effect)
  • the relative speed between the solid and the fluid

This is consistent with what we observe: a paper sheet or a flat wooden board will hover far better than a compact book, or a wooden ball.

The mass of a cow is expected to be between 600 kg and 1000 kg (ref. on Wikipedia), so slightly half of what we would expect for a car, but its surface is also less than a one half what is expected for a car. So I expect the effect of a tornado on a cow to be slightly lower of what is observed on a car. I must admit it is only an assumption, but I expect it to be conservative.

That being said, the Torro page on tornadoes says (extract):

  • T4 or Severe Tornado at 52-61 m/s (115-136 mph): Motorcars levitated. Mobile homes airborne / destroyed....
  • T5 or Intense Tornado at 62-72 m/s (137-160 mph): Heavier motor vehicles (4x4, 4 Tonne Trucks) levitated.

For the more common Enhanced Fujita scale T4 is more or less EF2, and T5 is roughly EF3 meaning strong tornadoes.

That means that such tornadoes could easily sweep a cow away, and probably levitate it a bit, like they do for motorcars between two shocks on the ground. But even if English is not my first language, the photograph shows something flying in the air much higher than what I would expect for being levitated.

What is cited in Torro scale is that mobile homes can be airborne in T4/EF2 tornadoes, but we now have more than one order of magnitude difference in surface without such a difference in weight. My conclusion is that according to the Torro scale which is consistent with the Enhanced Fujita scale, winds up to 135 mph could sweep a cow away and maybe levitate it but not make it fly.

(*) This site is documented as the reference for the Torro scale on Wikipedia.

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Serge Ballesta
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  • A similar answer was deleted yesterday, I wonder if deleted questions should be somehow locked and shaded but still visible to new users the same way it is for high-rep users. It could prevent duplication of effort and prevent people from answering with the same thing. – pipe Jan 26 '23 at 13:54
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    @pipe This is by the same person who posted that earlier deleted answer. I can't say whether it's any better than their first attempt because I can't see their first attempt and don't remember what it said. – F1Krazy Jan 26 '23 at 14:08
  • My first answer did contain a number of unreferenced assumptions the reason why I deleted it. Here I have tried to cite references with the Torro and Fujita scales which are based on observations. – Serge Ballesta Jan 26 '23 at 14:50
  • @pipe I can temporarily undelete my previous answer. I am new on this site and honnestly try my best to meet its quality rules. – Serge Ballesta Jan 26 '23 at 14:55
  • @F1Krazy [Image of the deleted answer](https://i.stack.imgur.com/YbRQt.png). The link is about [tornado classification](https://www.weather.gov/mkx/taw-tornado_classification_safety). – Laurel Jan 26 '23 at 15:59