Phones that are switched off, or on airplane mode, will also miss the warnings. But the government is clear that the system is an important tool, alongside more traditional methods of communication.
A Cabinet Office spokesperson says: “By issuing the alerts to devices connected to 4G and 5G networks, we expect the message to reach the vast majority of people during an actual crisis.”
“These alerts are just one of the many tools we have to spread information quickly in emergencies – such as television, radio, and online news, as well as emergency services going house to house knocking on doors.”
Forecasters at the Met Office agree that the system is invaluable when used alongside the most urgent weather warnings.
Chief Meteorologist Will Lang told BBC Weather: “The government’s Emergency Alert system can be used to supplement a red severe weather warning.
“It provides another layer of communication to reach people in imminent danger from any kind of hazard direct to their mobile phones when immediate action is needed to protect people’s lives.”
