Mobile phones across Newcastle and the Hunter are expected to sound a loud siren this afternoon as Australia tests its new national emergency warning system.

A test Critical Alert will be sent to compatible mobile devices across NSW at 2pm today, Monday 27 July.

The alert will be distributed nationally at the same time, with delivery times adjusted for each Australian time zone.

Most smartphones, along with some smartwatches and tablets connected to active 4G or 5G mobile networks, are expected to receive the test message.

Devices will vibrate, play a siren-like warning sound for about 10 seconds and display a message confirming it is an AusAlert test.

The alert will override silent and do not disturb settings, and people cannot opt out of receiving it through their device settings.

No action is required when the test message appears.

People using older devices or alternative operating systems may see the alert labelled as a “Presidential Alert” or “Extreme Threat Alert”, rather than AusAlert, but the content of the test message will remain the same.

Those who do not receive an alert also do not need to take any action.

A device may not receive the test if it is incompatible, switched off, in aeroplane mode, without mobile coverage or not running the latest software.

Some alerts may also arrive later than others depending on the device, mobile provider, software version and nearby mobile tower.

Anyone who uses a hidden or concealed phone for personal safety should be aware the alert may make the device easier to find.

People who cannot safely receive the test should turn the device off or place it in aeroplane mode before the scheduled alert.

AusAlert is scheduled to become operational in October 2026 and will be used to provide information during serious emergencies, including the location and severity of an incident and instructions about what people should do.

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