If you own any type of cellphone that can send and receives texts, you are going to receive a text message on September 20th that is called a "Presidential Alert." The test is being conducted by Federal Emergency Management Agency (FEMA) and the FCC, and will test both the Emergency Alert System (EAS) and Wireless Emergency Alerts (WEA). The latter will be tested at 2:18pm EDT (11:18am PDT) with the EAS test coming two minutes later.
The WEA test message will be sent out to all cellphones connected to a wireless provider that is a WEA member, and you can't opt out of it. This will be the first national WEA test, and it is expected to be broadcast over cell towers for a 30-minute period. Any cellphone that is powered on, connected to a WEA member's network, and is within range of an active cell tower will receive the message once.
The message will have a heading that reads "Presidential Alert," and will read, "THIS IS A TEST of the National Wireless Emergency Alert System. No action is needed." The alert will be used to warn the public about dangerous Weather conditions, missing children and other important news. The same ear-shattering tone used for AMBER alerts and Tornado warnings will introduce the message.
The reason why this test is taking place is to see whether the system works and what improvements need to be made. And we find it interesting, and a sign of the times, that FEMA's notes about the test mention that the WEA test does not collect any personal data. If there is some reason why the test cannot be conducted on September 20th, FEMA will try again on October 3rd at 2:18pm EDT.
This is the alert that cellphone users will see on September 20th
You might want to set an alarm for say, 2:15pm EDT for September 20. This way, you won't be startled by the tone three minutes later. In fact, you just might want to turn off your phone for a few minutes to avoid that sound completely.