Sirens and Test Alarm: National Warning Day on 10 September

Note: This text was translated from German by AI / (DeepL Pro)

Germany's National Warning Day takes place every year on the second Thursday of September, which falls on 10 September in 2026. On this day, the federal government, the states, and municipalities test whether their warning systems work reliably in a real emergency. At 11 a.m., they trigger a test warning, followed by the all-clear at approximately 11:45 a.m.

What to expect on Warning Day

Between 11 a.m. and 11:45 a.m., several warning channels operate simultaneously: sirens, the NINA and Katwarn warning apps, cell broadcast alerts on smartphones, radio and television, and the digital display boards operated by RNV (Rhein-Neckar-Verkehr GmbH). Anyone who receives a push notification or hears a siren during this time does not need to take any action. The main purpose of Warning Day is to test the technology: Do warning messages reach people quickly enough, and do the different channels work together reliably?

For anyone who is not yet familiar with the warning signals, the day also offers a chance to learn more about them. (only available in German)

Survey Following Warning Day

Starting 10 September, you can take part in a survey at warntag-umfrage.de and share your experiences and impressions of the Warning Day 2026.