What you should know about storm sirens, who sounds them, and when

Huntsville

Huntsville Madison County EMA

Data pix.

HUNTSVILLE, Ala. - Severe weather is headed our way again, which means you need to be on high alert for any possible danger. But there's another signal you may hear if you are outdoors during a tornado warning.

Sirens are for people outside of their homes. Once the National Weather Service in Huntsville issues a tornado warning, the Huntsville-Madison County Emergency Management Agency takes over.

Once the warning is issued, the shape of a polygon is drawn on a map by meteorologists at the National Weather Service. The Huntsville-Madison County EMA copies that drawing and sound the sirens. Anyone living inside that perimeter will hear it.

"If a siren is just a mile or so outside the box or half-mile outside the box it won't sound," said Emergency Management officer Scott Worsham. "That was done a few years ago to keep from alerting people that might not need the warning -- that may be miles away from the warning."

That polygon is considered the boundary of a tornado warning. The sirens will sound for up to 3 minutes at a time.

Remember, if you're outside and you hear the sirens, take cover immediately.