The droning wail of a tornado siren is ubiquitous in the southern and central parts of the United States. These loud sirens are meant to warn people who are outdoors that a tornado is on its way. Now that we're indoors or in a car for most of our lives, tornado sirens are all but useless, yet we keep wasting money on them.

Tornado forecasting wasn't all that impressive just a few decades ago. It wasn't until the 1990s that Doppler weather radar came into widespread use across the United States, giving forecasters the ability to see winds inside of a thunderstorm. This capability allows us to see rotation (and tornadoes) well before the twisters smash into towns downstream. Before Doppler radar, it took a classic hook echo on radar or a radio report that a neighboring town was destroyed to know that a tornado was on its way.

In the days before the internet, smartphones, and auto-activating weather radios, communities across the country repurposed their wartime air raid sirens for tornado alerts. These systems allowed people who were outside to run for shelter before the storm arrived and caught them hoeing away in the fields. That's the key, though—they're designed for people who are outside. You are not meant to hear tornado sirens indoors, especially today, when homes and businesses are able to muffle sound better than they were half a century ago.

There are millions of people across this country putting their lives on the line by listening for a sound they can't hear.

The latest money burn came from Madison County, Alabama, home of the state's fourth-largest city, Huntsville. The county and its cities recently announced that they will spend $750,000 on a digital upgrade of their tornado siren system, which is designed to limit siren activation to areas only within the tornado warning.

That is a pretty significant development that solves a major issue around tornado sirens—until they're given digital upgrades, they have to be activated for the entire county, even if only a small portion of the county is under a tornado warning. For those who can actually hear the sirens, this creates a crying wolf effect even larger than the one created by tornado warnings themselves (which carry about a 70% false alarm rate).

However, you're better off burning the money than wasting it on tornado sirens. Sure, some people have credited their lives to hearing a tornado siren and getting to shelter before the storm struck, but you'll find that people credit television meteorologists, weather radios, and cell phone alerts much more than tornado sirens these days.

Saturating communities with these sirens arguably puts them in more danger than if you recycled them and used the scrap metal for lawn darts. Tornado sirens create a dangerous dependency on these fragile, unreliable devices. People who live in areas with tornado sirens become dependent on them because they don't think they're in danger unless they hear the siren go off. The problem is, you usually can't hear them if you're inside! If the power goes out? They don't go off! If the wind is blowing the wrong way? The range of the sound is limited! Even people who live very close to a tornado siren can't hear them if they're sleeping, playing music, watching television, or are otherwise preoccupied.

If communities really want to help people protect themselves from life-threatening severe weather, they should demolish their siren systems and invest in automated weather radios. Remove the dependency on an unreliable system and replace them with life-saving radios right in your living room.

The National Weather Service broadcasts forecasts and warnings from radio antennas that cover nearly every square inch of the United States, and specially-designed weather radios can decode these signals and sound a loud tone when a severe weather watch or warning is issued for your county. Weather radios are smoke detectors for the weather, and they should be just as common in homes, schools, and business. These devices save lives—much more than tornado sirens ever could—and they're especially useful for households that don't have smartphones with wireless emergency alert capabilities.

Tornado sirens were a great idea fifty years ago, but they're increasingly obsolete and growing more dangerous with every severe storm that blows through. It's time to cut the cord and bring severe weather safety into the 21st century.

[Image: Daniel Rodriguez via Flickr]

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