Exact time & date every phone in Britain will be pinged with Emergency Alert that triggers loud siren for 10 seconds

MILLIONS of mobiles will blast out a deafening siren as the government tests its emergency alert system – designed to warn people of deadly storms, floods or terror threats.
The alarm will last around 10 seconds and will sound even if phones are set to silent.
It will happen at 3pm on Sunday, September 7, with the system expected to reach around 87 million devices across the UK.
Ministers say the alerts could save lives by giving people crucial warnings when danger is near, similar to systems already used in countries like the US and Japan.
Cabinet minister Pat McFadden said: “Emergency Alerts have the potential to save lives, allowing us to share essential information rapidly in emergency situations including extreme storms. Just like the fire alarm in your house, it’s important we test the system so that we know it will work if we need it.”
The last nationwide test in 2023 saw mobiles across the UK blare out the alert, and since then, the system has been triggered during major storms, floods, and even when a World War II bomb was discovered in Plymouth.
In January this year, 4.5 million people in Scotland and Northern Ireland received an alert as Storm Éowyn battered the UK with a red weather warning in place.
During Storm Darragh last December, 3.5 million people in Wales and the South West got an alert — the storm killed two people.
Police say the alerts were vital during the Plymouth evacuation, when more than 10,000 people were moved after the discovery of an unexploded bomb.
Tracey Lee, Chief Executive of Plymouth Council, said: “It played a vital role in helping us safely evacuate over 10,000 people and coordinate a complex, multi-agency response.”
Assistant Chief Constable Glen Mayhew added: “By their nature, emergency incidents occur with very little notice. They can develop at speed and across wide areas which puts lives at risk. This system has the ability to send an alert to those whose lives may be at risk, to ensure they can act to help themselves and others.”
The alerts work on all 4G and 5G networks, but phones must be switched on to receive them.
Special guidance is being issued to victims of domestic abuse with hidden phones, who may need to opt out to stay safe.
The message sent on September 7 will clearly state it is only a test.
The test comes alongside wider government plans to boost the UK’s resilience — including £1.3 billion for new biosecurity centres, £4.2 billion for flood defences, and the biggest pandemic exercise in Britain’s history, dubbed Exercise Pegasus.