Extreme-weather text alerts set to begin

Wireless carriers and the federal government are launching a system to automatically warn people of dangerous weather and other emergencies via a special type of text messaging to cellphones.

The Wireless Emergency Alerts (WEA) service, which begins this month, is free, and consumers won't have to sign up. Warnings will be location-based: If you're traveling, you'll get an alert for whatever emergency is happening where you are.

"Wireless carriers representing more than 97% of subscribers voluntarily agreed to develop and offer free, geographically targeted wireless emergency alerts," said Amy Storey, spokeswoman for the CTIA— The Wireless Association. AT&T, Cellcom, Cricket, Sprint Nextel, T-Mobile, U.S. Cellular and Verizon Wireless are participating.