AccuWeather.com

Build Your Own Tornado Machine

By Grace Muller, AccuWeather.com Staff Writer

Aug 9, 2011; 2:50 PM ET

With the click of a light switch and the whoosh of a hair dryer, Bob Smerbeck can unleash a tornado on his living room anytime he likes.

And he does, often.

Smerbeck, an expert senior meteorologist for AccuWeather.com, built a model tornado machine to look at how vortexes form.

How does it compare to a real tornado? Smerbeck's tiny tornado has a vortex about an inch wide. Real tornadoes can grow to up to a mile wide.

In the model, the air coming out of the plastic tubes makes the vapor inside the model swirl into a vortex. This is a very simplified version of what happens with supercell (rotating) thunderstorms that produce tornadoes.

In order to get a thunderstorm to rotate, winds throughout different levels of the atmosphere need to vary in direction, or turn with height above the ground. In order to get a tornado to form, that rotation within the thunderstorm itself needs to extend down from the thunderstorm to the ground.

In the model, a fan on top of the machine pulling up the air makes a vortex (or what looks like the tornado). This mimics the updraft that pulls the air of a real thunderstorm upward. An updraft allows a tighter and faster rotation of the vortex, which forms the tornado.

Tornadoes are visible because moist air condenses into water droplets. Smerbeck's model uses a vaporizer to see the vortex.

Smerbeck built his model tornado by following along with a video series made by Tornado Project Director Tom Grazulis.