Don't be alarmed if your phone goes off around 12:18pm on Wednesday. It is a nationwide test of the Emergency Alert System, and it allows the federal government to contact everyone with a phone in the event of a national emergency. Here is the official press release from Uncle Sam.

WASHINGTON – The Federal Emergency Management Agency (FEMA), in coordination with the Federal Communications Commission (FCC), will conduct a nationwide test of the Wireless Emergency Alert (WEA) and Emergency Alert System (EAS) on October 3, 2018. The WEA portion of the test commences at 2:18 p.m. EDT, and the EAS portion follows at 2:20 p.m. EDT. The test will assess the operational readiness of the infrastructure for distribution of a national message and determine whether technological improvements are needed. The test was postponed from September 20 due to hurricane Florence recovery efforts.

This is the fourth EAS nationwide test and the first national WEA test. The WEA test message will be sent to cell phones. Previous EAS national tests were conducted in September 2011, 2016 and 2017 in collaboration with the FCC, broadcasters, and emergency management officials in recognition of FEMA’s National Preparedness Month.

The WEA system is used to warn the public about dangerous weather, missing children, and other critical situations through alerts on cell phones. It allows customers whose wireless provider participates in WEA and who own a WEA compatible wireless phone to receive geo-targeted alerts of imminent threats to safety in their area through unique tones and vibration. The national WEA test will use the same special tone and vibration. The WEA test message will read: “THIS IS A TEST of the National Wireless Emergency Alert System. No action is needed.” Wireless phones will display the test message under the header “Presidential Alert.”

The WEA test will be sent through FEMA’s IPAWS, as part of the nation’s modern alert and warning infrastructure that automatically authenticates alerts. Cell towers will broadcast the WEA test for approximately 30 minutes. During this time, cell phones that are switched on and within range of an active cell tower should be capable of receiving the test message. Cell phones should receive the message once.

The EAS test is made available to EAS participants (i.e., radio and television broadcasters, cable systems, satellite radio and television providers, and wireline video providers) and is scheduled to last approximately one minute. The test message will be similar to regular monthly EAS test messages with which the public is familiar. The EAS message will include a reference to the WEA test: “THIS IS A TEST of the National Emergency Alert System. This system was developed by broadcast and cable operators in voluntary cooperation with the Federal Emergency Management Agency, the Federal Communications Commission, and local authorities to keep you informed in the event of an emergency. If this had been an actual emergency an official message would have followed the tone alert you heard at the start of this message. A similar wireless emergency alert test message has been sent to all cell phones nationwide. Some cell phones will receive the message; others will not. No action is required.

Significant coordination has been conducted with EAS Participants, wireless providers, and emergency managers in preparation for this WEA-EAS national test. The test is intended to ensure public safety officials have the methods and systems that will deliver urgent alerts and warnings to the public in times of an emergency or disaster. Periodic testing of public alert and warning systems is also a way to assess the operational readiness of the infrastructure required for the distribution of a national message and determine whether technological improvements are needed.

The EAS is based upon the War Powers Act provision of the Communications Act of 1934, which provides for Presidential access to commercial communications during “a state of public peril or disaster or other national emergency.”  For WEA, the Warning, Alert, and Response Network (WARN) Act of 2006 provides that subscribers may opt out of receiving any wireless alerts “other than an alert issued by the President,” and that wireless alerting service should allow wireless subscribers the capability of opting out of receiving WEA alerts, other than an alert issued at the direction of the President and/or his/her designee.

In the event of a national emergency, a Presidential WEA alert would be issued at the direction of the President and/or his/her designee, and activated by FEMA.