The FCC announced Tuesday the creation of an emergency alert system in New York City that can send messages to cell phones alerting residents of nearby threats to their safety.

The technology, dubbed the Personal Localized Alerting Network (PLAN), will be available to customers with AT&T, Sprint, T-Mobile USA and Verizon Wireless by the end of this year, four months ahead of schedule.

"One shortcoming that was exposed on 9/11 is that emergency authorities didn't have the ability to send alerts with vital instructions to people's mobile phones – nor the ability to break through network congestion," FCC Chairman Julius Genachowski said in prepared remarks. "Today, we announce that that's about to change."

PLAN ensures that emergency alerts will not get stalled by user congestion, which can happen with standard wireless services, especially when networks are flooded with traffic during emergency situations.

The technology allows the Federal Emergency Management Agency to aggregate alerts from national, state or local government officials, and then send those alerts to PLAN. The platform then authenticates the alert, verifies that the sender is authorized, and sends it to participating wireless carriers.

Wireless providers then push the alerts from cell towers to mobile phones compatible with the service in the affected area. The alerts appear like text messages on mobile devices and arrive at no charge to the subscriber.

Consumers will receive three types of alerts from PLAN: alerts issued by the President; alerts involving imminent threats to safety of life; and Amber Alerts. Participating carriers may allow subscribers to block all but Presidential alerts.

Participation in PLAN is voluntary, but carriers that chose to activate the free service must do so by April 2012 under the 2006 Warning, Alert and Response Network (WARN) Act.

AT&T, Sprint, T-Mobile and Verizon are deploying PLAN ahead of schedule in New York City. Verizon will also deploy the service in Washington, D.C., before the end of the year. The remaining carriers will launch the technology in their other markets in 2012, as will other wireless operators including Leap, MetroPCS, and U.S. Cellular.