How Tsunami Warnings Work

Tsunami warnings turn earthquake data, ocean sensors, forecast models and local evacuation calls into a race against coastal flooding.

1. Frame 1How tsunami warnings work: A NOAA warning center turns earthquake data into public safety alerts before coastal flooding reaches residents.
2. Frame 2Input gate: location, magnitude and depth cross thresholds; DART buoys and tide gauges check the water.
3. Frame 3Data path: forecast models map arrival times, danger zones and updates as measurements change.
4. Frame 4Local handoff: emergency managers convert warning, advisory or watch messages into evacuation routes, closures, sirens and phone alerts.
5. Frame 5Timing constraint: distant tsunamis may leave hours; nearby quakes can leave minutes and raise failure risk.
6. Frame 6Watch signal: alert level, first-wave arrival time, evacuation zone and all-clear notice decide the return threshold.