Alarm: Nationwide warning day makes cell phones ring on Thursday at 11 a.m.

On Thursday, September 11, 2025, the nationwide Warning Day will once again take place to rehearse for emergencies. On this day, the federal, state, and local authorities will jointly test their warning systems for crisis and disaster situations. At 11 a.m., the Federal Office of Civil Protection and Disaster Assistance (BBK) triggers a test warning via the Modular Warning System of the Federal Government (MoWaS).

Warning via cell phones, display boards, sirens, radio, and co.

The message is forwarded to connected warning multipliers such as radio and TV stations, warning apps, digital display boards, and, since 2022, also to millions of cell phones via cell broadcast. Many local authorities also use sirens and loudspeaker vans.

The warning apps NINA and Katwarn should also sound the alarm again—if they are installed. Warnings are also issued via cab roof signs, and even a coffee machine has dutifully delivered the alarm message to people in the past, although the latter was an oversight.

All clear at 11:45 a.m.

As in previous years, the all-clear will be given nationwide at 11:45 a.m. – except for the cell broadcast system, which can only send warnings, according to the BBK. The warning day will once again be accompanied by an online survey in which citizens can share their experiences with the various warning channels. According to the BBK, the warning channel with the widest reach is Cell Broadcast, which reached 73% of respondents according to the previous survey. This is followed by warning apps and siren signals with 59 percent each.

Participation in this year's survey is open until September 18, 2025, at www.warntag-umfrage.de. The feedback, together with technical analyses, will be incorporated into the further development of the warning system.

(mack)