Hi I'm Elliot and this is Mental Floss on YouTube, today I'm gonna talk about some misconceptions about the weather. 

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Misconception number 1: Lightning comes from the cloud down. Lightning comes from both clouds and the ground, but when we look at lightning, what we're seeing actually came from the ground. According to the National Severe Storms Laboratory, a typical cloud-to-ground flash lowers a path of negative electricity that we cannot see towards the ground in a series of spurts. Objects on the ground generally have a positive charge. Since opposites attract, an upwards streamer is sent out from the object about to be struck. When these two paths meet, a return stroke zips back up to the sky. It is the return stroke that produces the visible flash, but it all happens so fast - in about one-millionth of a second - so the human eye doesn't see the actual formation of the stroke. 

And now that you know how lightning works, misconception number 2: Lightning strikes the tallest object. Most likely it will strike the tallest object nearby because lightning is coming from both the ground and the sky, it is ideal to have less distance between those two things which is why buildings and towers get struck the most. But once the lightning coming from the sky gets closer to the ground, it's not able to make distinctions between objects and find the tallest one. It will be most attracted to tallest objects but might hit the ground or even a person instead. 

Misconception number 3: It can be too cold to snow. For it to snow, there's no requirement that it must be cold, but not too cold. The only necessity is water vapor in the air, but there probably will be less snow if it's very cold, because the air has less water vapor in it. In Antarctica, snow has been recorded in temperatures as low as negative 70 degrees Fahrenheit. 

Misconception number 4: A tsunami means a single, giant wave. It's worth mentioning this is probably the definition you'll see if you look up tsunami in a dictionary, but a tsunami is considered any sudden displacement of a large amount of water. Sometimes that means a bunch of smaller waves rather than one huge one, and those can be just as devastating. 

Misconception number 5: The Polar Vortex is new. Though we hear the term a lot in the news lately, there's nothing new about the polar vortex okay, the phrase dates back to 1853 when it was published in the magazine 'Household Words'. John Capper wrote an article about weather patterns and named the current around the north and south poles the 'Great Polar Vortex'. We have a similar meaning for the term nowadays, it refers to the two cyclones that rotate around Earth's two poles. Every once in a while, the polar vortex may shift and start affecting our weather, like it did in January 2014. Something similar happened in the late 1970s. 

Misconception number 6: Freezing rain means the raindrops are frozen. Actually the reason it's called "freezing rain" is because the drops freeze when they hit a surface, basically they fall through a lot of warmer air before they reach the really cold ground. This causes instantaneous freezing when a drop hits the surface like the ground or a car, and this is different from sleet, which freezes as it falls through the air. 

Misconception number 7: You can tell how far away a storm is by counting the seconds between when you see lightning and hear thunder. Okay, so, this is technically true, but most people have the details kind of wrong. People usually believe that the number of seconds between the lightning and thunder is the number of miles between you and the lightning. In fact, the lightning is even closer than that. The seconds counted needed to be divided by 5, and that is the actual distance. So, if you count 10 seconds between lightning and thunder, the lightning is a mere 2 miles away from you, sleep tight. 

Misconception number 8: Tornadoes don't go through mountains and cities. It's rare for when they hit a city but it actually does happen. For example, a tornado hit Oklahoma City in 1999 and a few years later, in 2007 one went through Atlanta, Georgia. It doesn't happen often because cities take up less space on land compared to rural areas, so statistically, tornadoes are more likely to hit the country. As for mountains, tornadoes have been recorded in peaks as high as 10,000 feet. They've been found in the Rocky Mountains, the Appalachian Mountains, and plenty of other mountain ranges. 

Misconception number 9: You're safe in a car during a tornado. So, people typically say this because cars can technically go faster than tornadoes, so outrunning one is possible, if not horribly terrifying, but if the tornado is strong it can potentially hurl a car through the air, so experts suggest that you take shelter in a house or basement instead of your car. In fact, The National Weather Service recommends that if you're near a tornado and can't be home, you should abandon your car and take shelter in a ditch or low area.

Which brings me to misconception number 10: Use a highway overpass as a storm shield. There have been some wildly publicized cases of people taking cover from tornadoes and storms underneath highway overpasses and being totally fine, but these were the exception, not the rule, and in fact, in some of these cases the news stories left out the fact that tornadoes didn't even directly hit that area. Many people have died doing this and meteorologists now believe that it might be the most dangerous place to be during a tornado. 

If you have a topic for an upcoming Misconceptions episode that you would like to see, leave it in the comments. Thank you for watching Misconceptions on Mental Floss on YouTube which was made with the help of all of these wonderful people, and I will see you next week. Goodbye!