Since I mentioned the communities in South Alabama in a recent post and asked you to take a moment and send a kind thought their way, I’d thought I would talk a little more about what a tornado actually is and does. Some of my readers are from parts of the world where tornadoes are less common than where I live and aren’t as familiar with what that kind of storm entails.

Also, as an update, the communities I told you about have been on the receiving end of such an outpouring of generosity that they have now asked that people stop sending donated items. They have the physical items they need to help the population at the moment, and are now in need of money and extra hands for clean-up and rebuilding.

As for my fellow writers, a lot of people will say that unless it’s pertinent to the story not to write about the weather. But sometimes, it makes a difference. And for worldbuilding purposes in Fantasy and Sci-Fi worlds, you might want to think about what kind of weather would make a difference. Perhaps the spaceship can’t enter the atmosphere in the spot it needs to because of a large lightning storm. Or maybe your wind mage is throwing a hissy fit that could level a town. Sometimes the weather does matter.

Anyway, here are ten things you might not know about tornadoes:

1. Tornadoes can and do form in every U.S. state and, in fact, have been recorded on every continent except Antartica. While they are more common in some regions than in others, and in some places are quite rare, they can form anywhere.
2. The most commonly affected place in the United States (and by a small margin, the world) is known as Tornado Alley and encompasses The Great Plains and large portions of the Southeast, though no exact boundaries have ever been defined. This is largely due to both geography and topography, specifically the areas between the Rocky Mountains and the Appalachian Mountains, with weather patterns greatly affected by the jet stream and the Gulf of Mexico.
3. A common misconception is that tornadoes cannot cross mountain ranges or bodies of water. While it’s not a common occurrence, storm cells have been recorded passing over mountain ranges. And a tornado passing over water is a common enough occurrence that a tornado over water has a special name–a waterspout.
4. In the current early warning system, a Tornado Watch means the storm conditions in the area are conducive to creating a tornado. A Tornado Warning means a tornado has been spotted on the ground or via radar and you should take cover immediately.
5. Tornado warning systems have steadily improved over the last seventy years (since the first warning system in 1948), but because of the nature of the type of storm, the longest warning times average about thirteen minutes. Most of the time, people in the affected area have less time than that to get to their safe place.
6. The tornado warning system has about a seventy percent false alarm rate because it’s better to be safe than sorry when strong funnel clouds start appearing on radar. However, this means that some (large portions) of the population don’t always take tornado warnings as seriously as they should. Also, some people wait to hear their local tornado siren, but it can be easily drowned out by the noise of the storm–or be destroyed by the storm before it has a chance to alert locals.
7. In a tornado, the safest place to be is underground, preferably in a concrete storm cellar. If no storm cellar is available, the bottom floor of a house or building, in a room with no exterior walls or windows, especially under stairs. In my house, my master bedroom closet is the only room that fits this description–and yes, I’ve dragged my kids and my dog into that closet with flashlights, snacks, a weather radio, blankets, and pillows when the local tornado sirens have sounded.
8. Tornadoes most commonly have wind speeds less than 110mph and are about 250 feet in diameter. They also only commonly travel a couple of miles before dissipating. The largest tornadoes on record, though, had wind speeds exceeding 300mph, diameters of approximately 2.5 miles, and traveled dozens of miles.
9. Tornadoes are rated on an EF scale. The EF stands for Enhanced Fujita and is an upgrade from the previous Fujita scale, named for the scientist who created it. The scale ranges from EF0–where a storm will down trees, but probably not cause significant damage to substantial structures–to an EF5–a storm that can rip houses off their foundations and pull large trees out of the ground or snap them in half. It is common for a tornado to have its rating on the EF scale upgraded after assessing the damage it caused.
10. A single tornado can be a single vortex or a multiple vortex grouping–meaning multiple funnel cloud formations that officially touch down to the ground, but all originate from the same cell.

So all you Fantasy writers out there with wind mages in your story, they are not to be underestimated!