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Warning Systems

    Tornadoes and severe thunderstorms can develop quickly, so an important component of a severe weather plan is a reliable warning system.  Warnings are disseminated through outdoor warning sirens, local television and radio stations, cable television systems, cell phone apps, and NOAA weather radio.  Find out how all these systems work and which are available to you.
    Public Warning Sirens are used in many towns to warn people of tornadoes.  However, rural areas and smaller towns do not have them.  If your community does have sirens, find out how they are used and if you can hear them.  Remember, even if a siren is nearby, they are intended as an outdoor warning system.  You may not be able to hear it inside your house.  When you hear sirens, do not call 911 to ask what is happening; instead, listen to NOAA Weather Radio or local radio or TV for the warning information.
    Most local radio and television stations broadcast storm warnings.  Cable television systems will also have warning information, sometimes on a designated channel.  However, satellite television stations do not provide local warnings unless you are watching a local station.
    Many smartphone apps are available to provide warning notification.  One particular service is the free Wireless Emergency Alerts provided through the Federal Emergency Management Agency.  The warnings are broadcast from cell towers in the vicinity of the tornado and flash flood, so you will receive them if you are near the hazard.
    A NOAA Weather Radio receiver will sound an alarm to alert you when a storm warning is issued.  It may be the only way you will learn of an impending storm; especially if you’re asleep, outdoors, or the electricity is off.  The receivers needed to receive the alarm are available at electronics stores.  Most models can operate on batteries; some are programmable to alert only for a single county or a portion of a county.  People who cannot receive a strong signal inside their building may need to use an external antenna.  More information about NOAA Weather Radio is available on our NOAA Weather Radio page.

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