Wireless emergency alerts soon available on your smartphone
Extreme weather alerts will soon be available in the palm of your hand.
Millions of smartphone users will begin receiving text messages from a sophisticated government system warning of dangerous weather and other emergencies.
The alerts are free and you don't sign up to get them. They're automatic.
Warnings are location-based, so if you're traveling, you'll receive an alert for whatever emergency is happening in your area.
The message will cause late-model smartphones to sound a special tone and vibrate.
Those who prefer not to get the warnings can opt out of the system.