Why is my mobile phone making that noise?

DEM Blogger

October 13, 2014

During severe weather events or other emergencies, you may have received notifications on your mobile phone that didn’t look like typical text messages. If you use an iOS device, it may have resembled the message shown to the right, appearing on your lock screen and heralded by a unique tone and vibration.

What you received is a wireless emergency alert (WEA), an emergency message that an authorized government agency can send through your cellular carrier to your phone. The intent of WEA technology is to provide immediate and location-specific alerting. WEA service rolled out in mid-2012 and all current mobile devices support it, though older devices may not.

WEA messages aren’t intended to replace other public alerting technologies. Rather, they’re another way to get urgent messages out in a hurry. If you receive a WEA message, it will include the nature of the emergency and brief instructions on what to do and where to get more information. In the example here, you’ll see a reference to “this area.” Part of the WEA system is the ability to choose a selected area and send the message through cellular towers in that area to nearby mobile devices – so if you receive the message, you know you’re in or very close to the affected area.

Currently, the list of alerting agencies includes the National Weather Service (NWS, as shown at right), the Department of Homeland Security (DHS), the Federal Emergency Management Agency (FEMA), the Federal Communications Commission (FCC), and some state and local public safety agencies. WEA alerts sent by these agencies are limited to extreme weather warnings, local emergencies that require evacuation or other immediate action, AMBER (missing child) alerts, and presidential notification of national emergencies.

For more information on WEA, see the National Weather Service’s Weather Ready Nation page of frequently asked questions (FAQs) or download FEMA’s WEA fact sheet.