Today every smartphone in America will receive a Presidential Alert – a forthcoming service via Wireless Emergency Alert System that Donald Trump is using in case of national emergency.
The message will go out to smartphones at 2.18pm ET Wednesday, as the US President tests how it will work in a new collaboration with The Federal Emergency Management Agency (FEMA).
It's very similar to Amber Alerts, however unlike the noisy notifications that warn people in a particular area of a child abduction - people cannot opt out of this one.
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Today every smartphone in America will receive a Presidential Alert at 2.18pm then TVs and radios will be interrupted at 2.20pm Wednesday by order of Donald Trump. Trump is seen above speaking in Mississippi during a rally Tuesday
Anyone within range of a working cell tower and with a mobile device that is switched on will receive the message on their screens whether they like it or not.
The FEMA website states that the cell network provider must participate in WEA in order for the message to go through.
Approximately 100 networks have deals with FEMA and the alerts are estimated to reach about 95 per cent of Americans.
This afternoon (or morning for those on the West Coast) there will be no need to respond though.
'THIS IS A TEST of the National Wireless Emergency Alert System,' the message will state. 'No action is needed.'
But the special tone and vibrations – broadcast twice - are not the only ones guaranteed to get the attention of people all over the country today. Within two minutes another message will go out.
The second one is will be a test of the Emergency Alert System that looks at the effectiveness of sending a message via broadcast, cable, satellite and wireless providers.