To learn ONLY about Tornadoes in the U.S. be sure to start listening at minute 10:05.

Tornadoes are a natural phenomenon that have occurred in all 50 U.S. states. They’ve actually occurred on all continents except Antarctica.

By definition, a tornado or twister in English is a "violent rotating column of air (National Weather Service)."

The reason we can see this air or wind is because dust, objects and debris are picked up due to the high pressure and high speed. The more pressure inside the tornado, the more power it has to destroy anything and everything in its path.

What differentiates the US from other places in the world when it comes to tornadoes is the sheer number. According to the National Severe Storms Laboratory, over one thousand two hundred tornadoes wreak havoc in the U.S. each year. Not all of them are severe, but the destruction costs the US around 5.4 Billion dollars in damages annually, not to mention the lives lost.

On average, around 70 people lose their lives to tornadoes in the U.S. each year. 

Tornado Alley is where the highest concentration of tornadoes in the U.S. are, and that region stretches from northern Texas to South Dakota. The states in this region are flat – we actually refer to them as the flatlands or the plains – and geographically, they’re east of the Rocky Mountains. The landscape alongside a combination of weather factors is what makes Tornado Alley a hotspot for activity.

Let’s try and understand the science of how tornadoes occur. We’ll start with air currents.

A current, is a body of water or air that moves in a specific direction. So if you’re swimming in the ocean, a lifeguard or the Coast Guard might warn you of strong currents, like a riptide that can pull people, boats or animals out into the ocean.

According to the National Severe Storms Library, air currents are created when warm air meets cool air. So between the poles and the equator, you’ll find air currents. In English, we call the four main air currents that affect our weather patterns, jet streams. Airplanes often take advantage of the wind’s speed – so this jet stream speed – to travel with less resistance to a destination. On average, wind in a jet stream moves between 80 and 140 miles per hour from west to east. So the same direction that the earth spins. This is why it’s quicker to travel from west to east than east to west.

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Mentioned In Episode

• The American English Accent Course
• Introduction Video from the Weather Channel