Illustrated tornado from the book The Wizard of Oz
W. R. Wright, Piglet Press Inc. (

Tornado Notification

Tornadoes are very destructive, so it's important to know when one may form so you can take shelter. Forecastors at the National Weather Service are always on the lookout for developing storms. Even though nobody knows how tornadoes form, they do know the conditions when they are most likely to form. When the conditions exist, the Storm Prediction Center in Norman, Oklahoma, issues a tornado watch. The watches usually last from four to six hours and usually cover a box from 20,000 to 40,000 square miles.

The local storm spotter network activates when a watch is issued. The spotters are trained to notice tornadoes as they form. If a spotter sees a tornado, the local Weather Service office will issue a tornado warning for the county or counties near the tornado. They can also issue warnings based on radar images. There are certain radar echos that are associated with tornadoes and they use the echos to forecast when a tornado will form.

You will hear about warnings issued for your county or parish through different ways. Many cities have tornado sirens which sound when a warning is issued. Also, the new Emergency Alert System can notify people over radio and television even if their radios and televisions are turned off. Another aspect of the EAS is it allows for site-specific warnings. If you live in one place you'll only hear warnings for you, not for some other place in the station's viewing or listening area.

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