They call me the tornado chaser. When the wind is up and conditions are right, I get in my car and follow violent storms. Crazy, some may say, but really I chase these sky beasts to learn about them. I want to share with you what I know. Tornadoes are rapidly rotating columns of air that form inside storms, then connect with the ground via a funnel of cloud. When that happens, they tear across the earth, posing a huge threat to life and property. Because of this, there's a great deal of research into these phenomena, but the truth is there's still a lot we don't know about how tornadoes form. The conditions that may give rise to one tornado won't necessarily cause another, but we have learned a lot since people first started recording tornadoes, like how to recognize the signs when one is brewing in the sky. Are you coming along for the ride? Tornadoes begin with a thunderstorm, but not just any thunderstorm. These are especially powerful towering thunderstorms called supercells, reaching up to over 50,000 feet. They bring high-force winds, giant hailstones, sometimes flooding, and great flashes of lightning. These are the kinds of storms that breed tornadoes, but only if there are also very specific conditions in place - clues that we can measure and look out for when we're trying to forecast a storm. Rising air is the first ingredient needed for a tornado to develop. Any storm is formed when condensation occurs. The byproducts of the clouds' condensation release heat, and heat becomes the energy that drives huge upward drafts of air. The more condensation and the bigger the storm clouds grow, the more powerful those updrafts become. In supercells, this rising air mass is particularly strong. As the air climbs, it can...