Japan faces devastating megaquake threat after 7.5 earthquake, tsunami

Wednesday, December 10, 2025 -A powerful magnitude‑7.5 earthquake struck off the northeastern coast of Japan late Monday — close to Aomori Prefecture — jolting communities from Hokkaido down through the Pacific‑coast region. 

The quake triggered tsunami warnings, prompted evacuations of roughly 90,000 residents, and led to injuries for dozens of people, though no catastrophic damage has (yet) been reported. Tsunami waves reached up to about 2 feet (about 70 cm) in some coastal ports before authorities downgraded warnings after the immediate risk passed.

In a rare move, the Japan Meteorological Agency (JMA) followed the quake with its first‑ever “megaquake” advisory under the nation’s newly updated warning system. 

The agency cautions that seismic stress from Monday’s event might increase the chance of a more powerful earthquake — magnitude 8.0 or higher — along nearby subduction zones in the coming week. While the probability is officially low, authorities are urging coastal residents to stay alert, review evacuation plans, and have emergency supplies ready.

Experts warn that if such a megaquake strikes — especially offshore — it could trigger a massive tsunami and cause catastrophic destruction across Japan’s Pacific‑facing coastline, potentially surpassing the devastation seen in the 2011 disaster. 

The advisory is not a prediction, but it serves as a stark reminder of Japan’s earthquake vulnerability — and of the need for communities to remain prepared, vigilant, and ready to act.